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Table of Contents

author

Represents the author of a change

Fields:

Name Description
email string

The email of the author
name string

The name of the author

authoring

The authors mapping between an origin and a destination

authoring.allowed

Create a list for an individual or team contributing code.

authoring_class authoring.allowed(default, allowlist)

Parameters:

Parameter Description
default string

The default author for commits in the destination. This is used in squash mode workflows or when users are not on the list.
allowlist sequence of string

List of authors in the origin that are allowed to contribute code. The authors must be unique

Examples:

Only pass thru allowed users:
authoring.allowed(
    default = "Foo Bar <noreply@foobar.com>",
    allowlist = [
       "someuser@myorg.com",
       "other@myorg.com",
       "another@myorg.com",
    ],
)
Only pass thru allowed LDAPs/usernames:

Some repositories are not based on email but use LDAPs/usernames. This is also supported since it is up to the origin how to check whether two authors are the same.

authoring.allowed(
    default = "Foo Bar <noreply@foobar.com>",
    allowlist = [
       "someuser",
       "other",
       "another",
    ],
)

authoring.overwrite

Use the default author for all the submits in the destination. Note that some destinations might choose to ignore this author and use the current user running the tool (In other words they don't allow impersonation).

authoring_class authoring.overwrite(default)

Parameters:

Parameter Description
default string

The default author for commits in the destination

Example:

Overwrite usage example:

Create an authoring object that will overwrite any origin author with noreply@foobar.com mail.

authoring.overwrite("Foo Bar <noreply@foobar.com>")

authoring.pass_thru

Use the origin author as the author in the destination, no filtering.

authoring_class authoring.pass_thru(default)

Parameters:

Parameter Description
default string

The default author for commits in the destination. This is used in squash mode workflows or if author cannot be determined.

Example:

Pass thru usage example:
authoring.pass_thru(default = "Foo Bar <noreply@foobar.com>")

authoring_class

The authors mapping between an origin and a destination

buildozer

Module for Buildozer-related functionality such as creating and modifying BUILD targets.

buildozer.cmd

Creates a Buildozer command. You can specify the reversal with the 'reverse' argument.

Command buildozer.cmd(forward, reverse=None)

Parameters:

Parameter Description
forward string

Specifies the Buildozer command, e.g. 'replace deps :foo :bar'
reverse string or NoneType

The reverse of the command. This is only required if the given command cannot be reversed automatically and the reversal of this command is required by some workflow or Copybara check. The following commands are automatically reversible:

  • add
  • remove (when used to remove element from list i.e. 'remove srcs foo.cc'
  • replace

buildozer.create

A transformation which creates a new build target and populates its attributes. This transform can reverse automatically to delete the target.

transformation buildozer.create(target, rule_type, commands=[], before='', after='')

Parameters:

Parameter Description
target string

Target to create, including the package, e.g. 'foo:bar'. The package can be '.' for the root BUILD file.
rule_type string

Type of this rule, for instance, java_library.
commands sequence of string or sequence of Command

Commands to populate attributes of the target after creating it. Elements can be strings such as 'add deps :foo' or objects returned by buildozer.cmd.
before string

When supplied, causes this target to be created before the target named by 'before'
after string

When supplied, causes this target to be created after the target named by 'after'

buildozer.delete

A transformation which is the opposite of creating a build target. When run normally, it deletes a build target. When reversed, it creates and prepares one.

transformation buildozer.delete(target, rule_type='', recreate_commands=[], before='', after='')

Parameters:

Parameter Description
target string

Target to create, including the package, e.g. 'foo:bar'
rule_type string

Type of this rule, for instance, java_library. Supplying this will cause this transformation to be reversible.
recreate_commands sequence of string or sequence of Command

Commands to populate attributes of the target after creating it. Elements can be strings such as 'add deps :foo' or objects returned by buildozer.cmd.
before string

When supplied with rule_type and the transformation is reversed, causes this target to be created before the target named by 'before'
after string

When supplied with rule_type and the transformation is reversed, causes this target to be created after the target named by 'after'

buildozer.modify

A transformation which runs one or more Buildozer commands against a single target expression. See http://go/buildozer for details on supported commands and target expression formats.

transformation buildozer.modify(target, commands)

Parameters:

Parameter Description
target string or sequence of string

Specifies the target(s) against which to apply the commands. Can be a list.
commands sequence of string or sequence of Command

Commands to apply to the target(s) specified. Elements can be strings such as 'add deps :foo' or objects returned by buildozer.cmd.

Examples:

Add a setting to one target:

Add "config = ':foo'" to foo/bar:baz:

buildozer.modify(
    target = 'foo/bar:baz',
    commands = [
        buildozer.cmd('set config ":foo"'),
    ],
)
Add a setting to several targets:

Add "config = ':foo'" to foo/bar:baz and foo/bar:fooz:

buildozer.modify(
    target = ['foo/bar:baz', 'foo/bar:fooz'],
    commands = [
        buildozer.cmd('set config ":foo"'),
    ],
)

change

A change metadata. Contains information like author, change message or detected labels

Fields:

Name Description
author author

The author of the change
date_time_iso_offset string

Return a ISO offset date time. Example: 2011-12-03T10:15:30+01:00'
first_line_message string

The message of the change
labels dict[string, string]

A dictionary with the labels detected for the change. If the label is present multiple times it returns the last value. Note that this is a heuristic and it could include things that are not labels.
labels_all_values dict[string, sequence of string]

A dictionary with the labels detected for the change. Note that the value is a collection of the values for each time the label was found. Use 'labels' instead if you are only interested in the last value. Note that this is a heuristic and it could include things that are not labels.
merge bool

Returns true if the change represents a merge
message string

The message of the change
original_author author

The author of the change before any mapping
ref string

Origin reference ref

ChangeMessage

Represents a well formed parsed change message with its associated labels.

Fields:

Name Description
first_line string

First line of this message
text string

The text description this message, not including the labels.

message.label_values

Returns a list of values associated with the label name.

sequence of string message.label_values(label_name)

Parameters:

Parameter Description
label_name string

The label name.

Changes

Data about the set of changes that are being migrated. Each change includes information like: original author, change message, labels, etc. You receive this as a field in TransformWork object for user defined transformations

Fields:

Name Description
current sequence of change

List of changes that will be migrated
migrated sequence of change

List of changes that where migrated in previous Copybara executions or if using ITERATIVE mode in previous iterations of this workflow.

Console

A console that can be used in skylark transformations to print info, warning or error messages.

console.error

Show an error in the log. Note that this will stop Copybara execution.

console.error(message)

Parameters:

Parameter Description
message string

message to log

console.info

Show an info message in the console

console.info(message)

Parameters:

Parameter Description
message string

message to log

console.progress

Show a progress message in the console

console.progress(message)

Parameters:

Parameter Description
message string

message to log

console.verbose

Show an info message in the console if verbose logging is enabled.

console.verbose(message)

Parameters:

Parameter Description
message string

message to log

console.warn

Show a warning in the console

console.warn(message)

Parameters:

Parameter Description
message string

message to log

core

Core functionality for creating migrations, and basic transformations.

Fields:

Name Description
console Console

Returns a handle to the console object.
main_config_path string

Location of the config file. This is subject to change

Command line flags:

Name Type Description
--allow-empty-diff boolean If set to false, Copybara will not write to the destination if the exact same change is already pending in the destination. Currently only supported for git.github_pr_destination and git.gerrit_destination.
--commands-timeout duration Commands timeout. Example values: 30s, 20m, 1h, etc.
--config-root string Configuration root path to be used for resolving absolute config labels like '//foo/bar'
--console-file-flush-interval duration How often Copybara should flush the console to the output file. (10s, 1m, etc.)If set to 0s, console will be flushed only at the end. Example values: 30s, 20m, 1h, etc.
--console-file-path string If set, write the console output also to the given file path.
--debug-file-break string Stop when file matching the glob changes
--debug-metadata-break boolean Stop when message and/or author changes
--debug-transform-break string Stop when transform description matches
--disable-reversible-check boolean If set, all workflows will be executed without reversible_check, overriding the workflow config and the normal behavior for CHANGE_REQUEST mode.
--dry-run boolean Run the migration in dry-run mode. Some destination implementations might have some side effects (like creating a code review), but never submit to a main branch.
--event-monitor list Eventmonitors to enable. These must be in the list of available monitors.
--fetch-timeout duration Fetch timeout. Example values: 30s, 20m, 1h, etc.
--force boolean Force the migration even if Copybara cannot find in the destination a change that is an ancestor of the one(s) being migrated. This should be used with care, as it could lose changes when migrating a previous/conflicting change.
--info-list-only boolean When set, the INFO command will print a list of workflows defined in the file.
--noansi boolean Don't use ANSI output for messages
--nocleanup boolean Cleanup the output directories. This includes the workdir, scratch clones of Git repos, etc. By default is set to false and directories will be cleaned prior to the execution. If set to true, the previous run output will not be cleaned up. Keep in mind that running in this mode will lead to an ever increasing disk usage.
--output-limit int Limit the output in the console to a number of records. Each subcommand might use this flag differently. Defaults to 0, which shows all the output.
--output-root string The root directory where to generate output files. If not set, ~/copybara/out is used by default. Use with care, Copybara might remove files inside this root if necessary.
--squash boolean Override workflow's mode with 'SQUASH'. This is useful mainly for workflows that use 'ITERATIVE' mode, when we want to run a single export with 'SQUASH', maybe to fix an issue. Always use --dry-run before, to test your changes locally.
--validate-starlark string Starlark should be validated prior to execution, but this might break legacy configs. Options are LOOSE, STRICT
-v, --verbose boolean Verbose output.

core.action

Create a dynamic Skylark action. This should only be used by libraries developers. Actions are Starlark functions that receive a context, perform some side effect and return a result (success, error or noop).

dynamic.action core.action(impl, params={})

Parameters:

Parameter Description
impl callable

The Skylark function to call
params dict

The parameters to the function. Will be available under ctx.params

core.copy

Copy files between directories and renames files

transformation core.copy(before, after, paths=glob(["**"]), overwrite=False, regex_groups={})

Parameters:

Parameter Description
before string

The name of the file or directory to copy. If this is the empty string and 'after' is a directory, then all files in the workdir will be copied to the sub directory specified by 'after', maintaining the directory tree.
after string

The name of the file or directory destination. If this is the empty string and 'before' is a directory, then all files in 'before' will be copied to the repo root, maintaining the directory tree inside 'before'.
paths glob or NoneType

A glob expression relative to 'before' if it represents a directory. Only files matching the expression will be copied. For example, glob(["**.java"]), matches all java files recursively inside 'before' folder. Defaults to match all the files recursively.
overwrite bool

Overwrite destination files if they already exist. Note that this makes the transformation non-reversible, since there is no way to know if the file was overwritten or not in the reverse workflow.
regex_groups dict

A set of named regexes that can be used to match part of the file name. Copybara uses re2 syntax. For example {"x": "[A-Za-z]+"}

Examples:

Copy a directory:

Move all the files in a directory to another directory:

core.copy("foo/bar_internal", "bar")

In this example, foo/bar_internal/one will be copied to bar/one.

Copy using Regex:

Change a file extension:

core.copy(before = 'foo/${x}.txt', after = 'foo/${x}.md', regex_groups = { 'x': '.*'})

In this example, foo/bar/README.txt will be copied to foo/bar/README.md.

Copy with reversal:

Copy all static files to a 'static' folder and use remove for reverting the change

core.transform(
    [core.copy("foo", "foo/static", paths = glob(["**.css","**.html", ]))],
    reversal = [core.remove(glob(['foo/static/**.css', 'foo/static/**.html']))]
)

core.dynamic_feedback

Create a dynamic Skylark feedback migration. This should only be used by libraries developers

dynamic.action core.dynamic_feedback(impl, params={})

Parameters:

Parameter Description
impl callable

The Skylark function to call
params dict

The parameters to the function. Will be available under ctx.params

core.dynamic_transform

Create a dynamic Skylark transformation. This should only be used by libraries developers

transformation core.dynamic_transform(impl, params={})

Parameters:

Parameter Description
impl callable

The Skylark function to call
params dict

The parameters to the function. Will be available under ctx.params

Examples:

Create a dynamic transformation without parameters:

To define a simple dynamic transformation, you don't even need to use core.dynamic_transform. The following transformation sets the change's message to uppercase.

def test(ctx):
  ctx.set_message(ctx.message.upper())

After defining this function, you can use test as a transformation in core.workflow.

Create a dynamic transformation with parameters:

If you want to create a library that uses dynamic transformations, you probably want to make them customizable. In order to do that, in your library.bara.sky, you need to hide the dynamic transformation (prefix with '_') and instead expose a function that creates the dynamic transformation with the param:

def _test_impl(ctx):
  ctx.set_message(ctx.message + ctx.params['name'] + str(ctx.params['number']) + '\n')

def test(name, number = 2):
  return core.dynamic_transform(impl = _test_impl,
                           params = { 'name': name, 'number': number})

After defining this function, you can use test('example', 42) as a transformation in core.workflow.

core.fail_with_noop

If invoked, it will fail the current migration as a noop

dynamic.action core.fail_with_noop(msg)

Parameters:

Parameter Description
msg string

The noop message

core.feedback

Defines a migration of changes' metadata, that can be invoked via the Copybara command in the same way as a regular workflow migrates the change itself.

It is considered change metadata any information associated with a change (pending or submitted) that is not core to the change itself. A few examples:

  • Comments: Present in any code review system. Examples: GitHub PRs or Gerrit code reviews.
  • Labels: Used in code review systems for approvals and/or CI results. Examples: GitHub labels, Gerrit code review labels.
For the purpose of this workflow, it is not considered metadata the commit message in Git, or any of the contents of the file tree.

core.feedback(name, origin, destination, actions=[], description=None)

Parameters:

Parameter Description
name string

The name of the feedback workflow.
origin trigger

The trigger of a feedback migration.
destination endpoint_provider

Where to write change metadata to. This is usually a code review system like Gerrit or GitHub PR.
actions sequence

A list of feedback actions to perform, with the following semantics:
- There is no guarantee of the order of execution.
- Actions need to be independent from each other.
- Failure in one action might prevent other actions from executing.
description string or NoneType

A description of what this workflow achieves

core.filter_replace

Applies an initial filtering to find a substring to be replaced and then applies a mapping of replaces for the matched text.

filter_replace core.filter_replace(regex, mapping={}, group=Whole text, paths=glob(["**"]), reverse=regex)

Parameters:

Parameter Description
regex string

A re2 regex to match a substring of the file
mapping unknown

A mapping function like core.replace_mapper or a dict with mapping values.
group int or NoneType

Extract a regex group from the matching text and pass this as parameter to the mapping instead of the whole matching text.
paths glob or NoneType

A glob expression relative to the workdir representing the files to apply the transformation. For example, glob(["**.java"]), matches all java files recursively. Defaults to match all the files recursively.
reverse string or NoneType

A re2 regex used as reverse transformation

Examples:

Simple replace with mapping:

Simplest mapping

core.filter_replace(
    regex = 'a.*',
    mapping = {
        'afoo': 'abar',
        'abaz': 'abam'
    }
)
TODO replace:

This replace is similar to what it can be achieved with core.todo_replace:

core.filter_replace(
    regex = 'TODO\\((.*?)\\)',
    group = 1,
        mapping = core.replace_mapper([
            core.replace(
                before = '${p}foo${s}',
                after = '${p}fooz${s}',
                regex_groups = { 'p': '.*', 's': '.*'}
            ),
            core.replace(
                before = '${p}baz${s}',
                after = '${p}bazz${s}',
                regex_groups = { 'p': '.*', 's': '.*'}
            ),
        ],
        all = True
    )
)

core.format

Formats a String using Java's String.format.

string core.format(format, args)

Parameters:

Parameter Description
format string

The format string
args sequence

The arguments to format

core.latest_version

Selects the latest version that matches the format. Using --force in the CLI will force to use the reference passed as argument instead.

VersionSelector core.latest_version(format, regex_groups={})

Parameters:

Parameter Description
format string

The format of the version. If using it for git, it has to use the completerefspec (e.g. 'refs/tags/${n0}.${n1}.${n2}')
regex_groups dict

A set of named regexes that can be used to match part of the versions. Copybara uses re2 syntax. Use the following nomenclature n0, n1, n2 for the version part (will use numeric sorting) or s0, s1, s2 (alphabetic sorting). Note that there can be mixed but the numbers cannot be repeated. In other words n0, s1, n2 is valid but not n0, s0, n1. n0 has more priority than n1. If there are fields where order is not important, use s(N+1) where N ist he latest sorted field. Example {"n0": "[0-9]+", "s1": "[a-z]+"}

Example:

Version selector for Git tags:

Example of how to match tags that follow semantic versioning

core.latest_version(
    format = "refs/tags/${n0}.${n1}.${n2}",    regex_groups = {
        'n0': '[0-9]+',        'n1': '[0-9]+',        'n2': '[0-9]+',    })

core.move

Moves files between directories and renames files

transformation core.move(before, after, paths=glob(["**"]), overwrite=False, regex_groups={})

Parameters:

Parameter Description
before string

The name of the file or directory before moving. If this is the empty string and 'after' is a directory, then all files in the workdir will be moved to the sub directory specified by 'after', maintaining the directory tree.
after string

The name of the file or directory after moving. If this is the empty string and 'before' is a directory, then all files in 'before' will be moved to the repo root, maintaining the directory tree inside 'before'.
paths glob or NoneType

A glob expression relative to 'before' if it represents a directory. Only files matching the expression will be moved. For example, glob(["**.java"]), matches all java files recursively inside 'before' folder. Defaults to match all the files recursively.
overwrite bool

Overwrite destination files if they already exist. Note that this makes the transformation non-reversible, since there is no way to know if the file was overwritten or not in the reverse workflow.
regex_groups dict

A set of named regexes that can be used to match part of the file name. Copybara uses re2 syntax. For example {"x": "[A-Za-z]+"}

Examples:

Move a directory:

Move all the files in a directory to another directory:

core.move("foo/bar_internal", "bar")

In this example, foo/bar_internal/one will be moved to bar/one.

Move all the files to a subfolder:

Move all the files in the checkout dir into a directory called foo:

core.move("", "foo")

In this example, one and two/bar will be moved to foo/one and foo/two/bar.

Move a subfolder's content to the root:

Move the contents of a folder to the checkout root directory:

core.move("foo", "")

In this example, foo/bar would be moved to bar.

Move using Regex:

Change a file extension:

core.move(before = 'foo/${x}.txt', after = 'foo/${x}.md', regex_groups = { 'x': '.*'})

In this example, foo/bar/README.txt will be moved to foo/bar/README.md.

core.remove

Remove files from the workdir. This transformation is only meant to be used inside core.transform for reversing core.copy like transforms. For regular file filtering use origin_files exclude mechanism.

transformation core.remove(paths)

Parameters:

Parameter Description
paths glob

The files to be deleted

Examples:

Reverse a file copy:

Move all the files in a directory to another directory:

core.transform(
    [core.copy("foo", "foo/public")],
    reversal = [core.remove(glob(["foo/public/**"]))])

In this example, foo/one will be moved to foo/public/one.

Copy with reversal:

Copy all static files to a 'static' folder and use remove for reverting the change

core.transform(
    [core.copy("foo", "foo/static", paths = glob(["**.css","**.html", ]))],
    reversal = [core.remove(glob(['foo/static/**.css', 'foo/static/**.html']))]
)

core.replace

Replace a text with another text using optional regex groups. This transformation can be automatically reversed.

transformation core.replace(before, after, regex_groups={}, paths=glob(["**"]), first_only=False, multiline=False, repeated_groups=False, ignore=[])

Parameters:

Parameter Description
before string

The text before the transformation. Can contain references to regex groups. For example "foo${x}text".

before can only contain 1 reference to each unique regex_group. If you require multiple references to the same regex_group, add repeated_groups: True.

If '$' literal character needs to be matched, '$$' should be used. For example '$$FOO' would match the literal '$FOO'. [Note this argument is a string. If you want to match a regular expression it must be encoded as a regex_group.]
after string

The text after the transformation. It can also contain references to regex groups, like 'before' field.
regex_groups dict

A set of named regexes that can be used to match part of the replaced text.Copybara uses re2 syntax. For example {"x": "[A-Za-z]+"}
paths glob or NoneType

A glob expression relative to the workdir representing the files to apply the transformation. For example, glob(["**.java"]), matches all java files recursively. Defaults to match all the files recursively.
first_only bool

If true, only replaces the first instance rather than all. In single line mode, replaces the first instance on each line. In multiline mode, replaces the first instance in each file.
multiline bool

Whether to replace text that spans more than one line.
repeated_groups bool

Allow to use a group multiple times. For example foo${repeated}/${repeated}. Note that this won't match "fooX/Y". This mechanism doesn't use backtracking. In other words, the group instances are treated as different groups in regex construction and then a validation is done after that.
ignore sequence

A set of regexes. Any line that matches any expression in this set, which might otherwise be transformed, will be ignored.

Examples:

Simple replacement:

Replaces the text "internal" with "external" in all java files

core.replace(
    before = "internal",
    after = "external",
    paths = glob(["**.java"]),
)
Append some text at the end of files:
core.replace(
   before = '${end}',
   after  = 'Text to be added at the end',
   multiline = True,
   regex_groups = { 'end' : '\\z'},
)
Append some text at the end of files reversible:

Same as the above example but make the transformation reversible

core.transform([
    core.replace(
       before = '${end}',
       after  = 'some append',
       multiline = True,
       regex_groups = { 'end' : r'\z'},
    )
],
reversal = [
    core.replace(
       before = 'some append${end}',
       after = '',
       multiline = True,
       regex_groups = { 'end' : r'\z'},
    )])
Replace using regex groups:

In this example we map some urls from the internal to the external version in all the files of the project.

core.replace(
        before = "https://some_internal/url/${pkg}.html",
        after = "https://example.com/${pkg}.html",
        regex_groups = {
            "pkg": ".*",
        },
    )

So a url like https://some_internal/url/foo/bar.html will be transformed to https://example.com/foo/bar.html.

Remove confidential blocks:

This example removes blocks of text/code that are confidential and thus shouldn'tbe exported to a public repository.

core.replace(
        before = "${x}",
        after = "",
        multiline = True,
        regex_groups = {
            "x": "(?m)^.*BEGIN-INTERNAL[\\w\\W]*?END-INTERNAL.*$\\n",
        },
    )

This replace would transform a text file like:

This is
public
 // BEGIN-INTERNAL
 confidential
 information
 // END-INTERNAL
more public code
 // BEGIN-INTERNAL
 more confidential
 information
 // END-INTERNAL

Into:

This is
public
more public code

core.replace_mapper

A mapping function that applies a list of replaces until one replaces the text (Unless all = True is used). This should be used with core.filter_replace or other transformations that accept text mapping as parameter.

mapping_function core.replace_mapper(mapping, all=False)

Parameters:

Parameter Description
mapping sequence of transformation

The list of core.replace transformations
all bool

Run all the mappings despite a replace happens.

core.reverse

Given a list of transformations, returns the list of transformations equivalent to undoing all the transformations

sequence of transformation core.reverse(transformations)

Parameters:

Parameter Description
transformations sequence of transformation

The transformations to reverse

core.todo_replace

Replace Google style TODOs. For example TODO(username, othername).

transformation core.todo_replace(tags=['TODO', 'NOTE'], mapping={}, mode='MAP_OR_IGNORE', paths=glob(["**"]), default=None, ignore=None)

Parameters:

Parameter Description
tags sequence of string

Prefix tag to look for
mapping dict

Mapping of users/strings
mode string

Mode for the replace:

  • 'MAP_OR_FAIL': Try to use the mapping and if not found fail.
  • 'MAP_OR_IGNORE': Try to use the mapping but ignore if no mapping found.
  • 'MAP_OR_DEFAULT': Try to use the mapping and use the default if not found.
  • 'SCRUB_NAMES': Scrub all names from TODOs. Transforms 'TODO(foo)' to 'TODO'
  • 'USE_DEFAULT': Replace any TODO(foo, bar) with TODO(default_string)
paths glob or NoneType

A glob expression relative to the workdir representing the files to apply the transformation. For example, glob(["**.java"]), matches all java files recursively. Defaults to match all the files recursively.
default string or NoneType

Default value if mapping not found. Only valid for 'MAP_OR_DEFAULT' or 'USE_DEFAULT' modes
ignore string or NoneType

If set, elements within TODO (with usernames) that match the regex will be ignored. For example ignore = "foo" would ignore "foo" in "TODO(foo,bar)" but not "bar".

Examples:

Simple update:

Replace TODOs and NOTES for users in the mapping:

core.todo_replace(
  mapping = {
    'test1' : 'external1',
    'test2' : 'external2'
  }
)

Would replace texts like TODO(test1) or NOTE(test1, test2) with TODO(external1) or NOTE(external1, external2)

Scrubbing:

Remove text from inside TODOs

core.todo_replace(
  mode = 'SCRUB_NAMES'
)

Would replace texts like TODO(test1): foo or NOTE(test1, test2):foo with TODO:foo and NOTE:foo

Ignoring Regex Patterns:

Ignore regEx inside TODOs when scrubbing/mapping

core.todo_replace(
  mapping = { 'aaa' : 'foo'},
  ignore = 'b/.*'
)

Would replace texts like TODO(b/123, aaa) with TODO(b/123, foo)

core.transform

Groups some transformations in a transformation that can contain a particular, manually-specified, reversal, where the forward version and reversed version of the transform are represented as lists of transforms. The is useful if a transformation does not automatically reverse, or if the automatic reversal does not work for some reason.
If reversal is not provided, the transform will try to compute the reverse of the transformations list.

transformation core.transform(transformations, reversal=The reverse of 'transformations', ignore_noop=None, noop_behavior=NOOP_IF_ANY_NOOP)

Parameters:

Parameter Description
transformations sequence of transformation

The list of transformations to run as a result of running this transformation.
reversal sequence of transformation or NoneType

The list of transformations to run as a result of running this transformation in reverse.
ignore_noop bool or NoneType

WARNING: Deprecated. Use noop_behavior instead.
In case a noop error happens in the group of transformations (Both forward and reverse), it will be ignored, but the rest of the transformations in the group will still be executed. If ignore_noop is not set, we will apply the closest parent's ignore_noop.
noop_behavior string or NoneType

How to handle no-op transformations:

  • 'IGNORE_NOOP': Any no-ops among the wrapped transformations are ignored.
  • 'NOOP_IF_ANY_NOOP': Throws an exception as soon as a single wrapped transformation is a no-op.
  • 'NOOP_IF_ALL_NOOP': Ignores no-ops from the wrapped transformations unless they all no-op, in which case an exception is thrown.

core.verify_match

Verifies that a RegEx matches (or not matches) the specified files. Does not transform anything, but will stop the workflow if it fails.

transformation core.verify_match(regex, paths=glob(["**"]), verify_no_match=False, also_on_reversal=False)

Parameters:

Parameter Description
regex string

The regex pattern to verify. To satisfy the validation, there has to be atleast one (or no matches if verify_no_match) match in each of the files included in paths. The re2j pattern will be applied in multiline mode, i.e. '^' refers to the beginning of a file and '$' to its end. Copybara uses re2 syntax.
paths glob or NoneType

A glob expression relative to the workdir representing the files to apply the transformation. For example, glob(["**.java"]), matches all java files recursively. Defaults to match all the files recursively.
verify_no_match bool

If true, the transformation will verify that the RegEx does not match.
also_on_reversal bool

If true, the check will also apply on the reversal. The default behavior is to not verify the pattern on reversal.

core.workflow

Defines a migration pipeline which can be invoked via the Copybara command.

Implicit labels that can be used/exposed:

  • COPYBARA_CONTEXT_REFERENCE: Requested reference. For example if copybara is invoked as copybara copy.bara.sky workflow master, the value would be master.
  • COPYBARA_LAST_REV: Last reference that was migrated
  • COPYBARA_CURRENT_REV: The current reference being migrated
  • COPYBARA_CURRENT_REV_DATE_TIME: Date & time for the current reference being migrated in ISO format (Example: "2011-12-03T10:15:30+01:00")
  • COPYBARA_CURRENT_MESSAGE: The current message at this point of the transformations
  • COPYBARA_CURRENT_MESSAGE_TITLE: The current message title (first line) at this point of the transformations
  • COPYBARA_AUTHOR: The author of the change

core.workflow(name, origin, destination, authoring, transformations=[], origin_files=glob(["**"]), destination_files=glob(["**"]), mode="SQUASH", reversible_check=True for 'CHANGE_REQUEST' mode. False otherwise, check_last_rev_state=False, ask_for_confirmation=False, dry_run=False, after_migration=[], after_workflow=[], change_identity=None, set_rev_id=True, smart_prune=False, migrate_noop_changes=False, experimental_custom_rev_id=None, description=None, checkout=True, reversible_check_ignore_files=None)

Parameters:

Parameter Description
name string

The name of the workflow.
origin origin

Where to read from the code to be migrated, before applying the transformations. This is usually a VCS like Git, but can also be a local folder or even a pending change in a code review system like Gerrit.
destination destination

Where to write to the code being migrated, after applying the transformations. This is usually a VCS like Git, but can also be a local folder or even a pending change in a code review system like Gerrit.
authoring authoring_class

The author mapping configuration from origin to destination.
transformations sequence

The transformations to be run for this workflow. They will run in sequence.
origin_files glob or NoneType

A glob relative to the workdir that will be read from the origin during the import. For example glob(["**.java"]), all java files, recursively, which excludes all other file types.
destination_files glob or NoneType

A glob relative to the root of the destination repository that matches files that are part of the migration. Files NOT matching this glob will never be removed, even if the file does not exist in the source. For example glob([''], exclude = ['/BUILD']) keeps all BUILD files in destination when the origin does not have any BUILD files. You can also use this to limit the migration to a subdirectory of the destination, e.g. glob(['java/src/'], exclude = ['/BUILD']) to only affect non-BUILD files in java/src.
mode string

Workflow mode. Currently we support four modes:

  • 'SQUASH': Create a single commit in the destination with new tree state.
  • 'ITERATIVE': Import each origin change individually.
  • 'CHANGE_REQUEST': Import a pending change to the Source-of-Truth. This could be a GH Pull Request, a Gerrit Change, etc. The final intention should be to submit the change in the SoT (destination in this case).
  • 'CHANGE_REQUEST_FROM_SOT': Import a pending change from the Source-of-Truth. This mode is useful when, despite the pending change being already in the SoT, the users want to review the code on a different system. The final intention should never be to submit in the destination, but just review or test
reversible_check bool or NoneType

Indicates if the tool should try to to reverse all the transformations at the end to check that they are reversible.
The default value is True for 'CHANGE_REQUEST' mode. False otherwise
check_last_rev_state bool

If set to true, Copybara will validate that the destination didn't change since last-rev import for destination_files. Note that this flag doesn't work for CHANGE_REQUEST mode.
ask_for_confirmation bool

Indicates that the tool should show the diff and require user's confirmation before making a change in the destination.
dry_run bool

Run the migration in dry-run mode. Some destination implementations might have some side effects (like creating a code review), but never submit to a main branch.
after_migration sequence

Run a feedback workflow after one migration happens. This runs once per change in ITERATIVE mode and only once for SQUASH.
after_workflow sequence

Run a feedback workflow after all the changes for this workflow run are migrated. Prefer after_migration as it is executed per change (in ITERATIVE mode). Tasks in this hook shouldn't be critical to execute. These actions shouldn't record effects (They'll be ignored).
change_identity string or NoneType

By default, Copybara hashes several fields so that each change has an unique identifier that at the same time reuses the generated destination change. This allows to customize the identity hash generation so that the same identity is used in several workflows. At least ${copybara_config_path} has to be present. Current user is added to the hash automatically.

Available variables:

  • ${copybara_config_path}: Main config file path
  • ${copybara_workflow_name}: The name of the workflow being run
  • ${copybara_reference}: The requested reference. In general Copybara tries its best to give a repetable reference. For example Gerrit change number or change-id or GitHub Pull Request number. If it cannot find a context reference it uses the resolved revision.
  • ${label:label_name}: A label present for the current change. Exposed in the message or not.
If any of the labels cannot be found it defaults to the default identity (The effect would be no reuse of destination change between workflows)
set_rev_id bool

Copybara adds labels like 'GitOrigin-RevId' in the destination in order to track what was the latest change imported. For CHANGE_REQUEST workflows it is not used and is purely informational. This field allows to disable it for that mode. Destinations might ignore the flag.
smart_prune bool

By default CHANGE_REQUEST workflows cannot restore scrubbed files. This flag does a best-effort approach in restoring the non-affected snippets. For now we only revert the non-affected files. This only works for CHANGE_REQUEST mode.
migrate_noop_changes bool

By default, Copybara tries to only migrate changes that affect origin_files or config files. This flag allows to include all the changes. Note that it might generate more empty changes errors. In ITERATIVE mode it might fail if some transformation is validating the message (Like has to contain 'PUBLIC' and the change doesn't contain it because it is internal).
experimental_custom_rev_id string or NoneType

Use this label name instead of the one provided by the origin. This is subject to change and there is no guarantee.
description string or NoneType

A description of what this workflow achieves
checkout bool

Allows disabling the checkout. The usage of this feature is rare. This could be used to update a file of your own repo when a dependant repo version changes and you are not interested on the files of the dependant repo, just the new version.
reversible_check_ignore_files glob or NoneType

Ignore the files matching the glob in the reversible check

Command line flags:

Name Type Description
--change-request-from-sot-limit int Number of origin baseline changes to use for trying to match one in the destination. It can be used if the are many parent changes in the origin that are a no-op in the destination
--change-request-from-sot-retry list Number of retries and delay between retries when we cannot find the baseline in the destination for CHANGE_REQUEST_FROM_SOT. For example '10,30,60' will retry three times. The first retry will be delayed 10s, the second one 30s and the third one 60s
--change-request-parent, --change_request_parent string Commit revision to be used as parent when importing a commit using CHANGE_REQUEST workflow mode. This shouldn't be needed in general as Copybara is able to detect the parent commit message.
--check-last-rev-state boolean If enabled, Copybara will validate that the destination didn't change since last-rev import for destination_files. Note that this flag doesn't work for CHANGE_REQUEST mode.
--default-author string Use this author as default instead of the one in the config file.Format should be 'Foo Bar foobar@example.com'
--diff-in-origin boolean When this flag is enabled, copybara will show different changes between last Revision and current revision in origin instead of in destination. NOTE: it Only works for SQUASH and ITERATIVE
--force-author author Force the author to this. Note that this only changes the author before the transformations happen, you can still use the transformations to alter it.
--force-message string Force the change description to this. Note that this only changes the message before the transformations happen, you can still use the transformations to alter it.
--ignore-noop boolean Only warn about operations/transforms that didn't have any effect. For example: A transform that didn't modify any file, non-existent origin directories, etc.
--import-noop-changes boolean By default Copybara will only try to migrate changes that could affect the destination. Ignoring changes that only affect excluded files in origin_files. This flag disables that behavior and runs for all the changes.
--init-history boolean Import all the changes from the beginning of the history up to the resolved ref. For 'ITERATIVE' workflows this will import individual changes since the first one. For 'SQUASH' it will import the squashed change up to the resolved ref. WARNING: Use with care, this flag should be used only for the very first run of Copybara for a workflow.
--iterative-limit-changes int Import just a number of changes instead of all the pending ones
--last-rev string Last revision that was migrated to the destination
--nosmart-prune boolean Disable smart prunning
--notransformation-join boolean By default Copybara tries to join certain transformations in one so that it is more efficient. This disables the feature.
--read-config-from-change boolean For each imported origin change, load the workflow's origin_files, destination_files and transformations from the config version of that change. The rest of the fields (more importantly, origin and destination) cannot change and the version from the first config will be used.
--same-version boolean Re-import the last version imported. This is useful for example to check that a refactor in a copy.bara.sky file doesn't introduce accidental changes.
--squash-skip-history boolean Avoid exposing the history of changes that are being migrated. This is useful when we want to migrate a new repository but we don't want to expose all the change history to metadata.squash_notes.
--threads int Number of threads to use when running transformations that change lot of files
--threads-min-size int Minimum size of the lists to process to run them in parallel
--to-folder boolean Sometimes a user wants to test what the outcome would be for a workflow without changing the configuration or adding an auxiliary testing workflow. This flags allowsto change an existing workflow to use folder.destination
--workflow-identity-user string Use a custom string as a user for computing change identity

destination_effect

Represents an effect that happened in the destination due to a single migration

Fields:

Name Description
destination_ref destination_ref

Destination reference updated/created. Might be null if there was no effect. Might be set even if the type is error (For example a synchronous presubmit test failed but a review was created).
errors sequence of string

List of errors that happened during the migration
origin_refs sequence of origin_ref

List of origin changes that were included in this migration
summary string

Textual summary of what happened. Users of this class should not try to parse this field.
type string

Return the type of effect that happened: CREATED, UPDATED, NOOP, INSUFFICIENT_APPROVALS or ERROR

destination_reader

Handle to read from the destination

destination_reader.copy_destination_files

Copy files from the destination into the workdir.

destination_reader.copy_destination_files(glob)

Parameters:

Parameter Description
glob glob

Files to copy to the workdir, potentially overwriting files checked out from the origin.

Example:

Copy files from the destination's baseline:

This can be added to the transformations of your core.workflow:

def _copy_destination_file(ctx):
   content = ctx.destination_reader().copy_destination_files(glob(include = ['path/to/**']))

transforms = [core.dynamic_transform(_copy_destination_file)]

Would copy all files in path/to/ from the destination baseline to the copybara workdir. The files do not have to be covered by origin_files nor destination_files, but will cause errors if they are not covered by destination_files and not moved or deleted.

destination_reader.file_exists

Checks whether a given file exists in the destination.

bool destination_reader.file_exists(path)

Parameters:

Parameter Description
path string

Path to the file.

destination_reader.read_file

Read a file from the destination.

string destination_reader.read_file(path)

Parameters:

Parameter Description
path string

Path to the file.

Example:

Read a file from the destination's baseline:

This can be added to the transformations of your core.workflow:

def _read_destination_file(ctx):
    content = ctx.destination_reader().read_file(path = 'path/to/my_file.txt')
    ctx.console.info(content)

    transforms = [core.dynamic_transform(_read_destination_file)]

Would print out the content of path/to/my_file.txt in the destination. The file does not have to be covered by origin_files nor destination_files.

destination_ref

Reference to the change/review created/updated on the destination.

Fields:

Name Description
id string

Destination reference id
type string

Type of reference created. Each destination defines its own and guarantees to be more stable than urls/ids
url string

Url, if any, of the destination change

endpoint

An origin or destination API in a feedback migration.

Fields:

Name Description
url string

Return the URL of this endpoint.

endpoint.new_destination_ref

Creates a new destination reference out of this endpoint.

destination_ref endpoint.new_destination_ref(ref, type, url=None)

Parameters:

Parameter Description
ref string

The reference.
type string

The type of this reference.
url string or NoneType

The url associated with this reference, if any.

endpoint.new_origin_ref

Creates a new origin reference out of this endpoint.

origin_ref endpoint.new_origin_ref(ref)

Parameters:

Parameter Description
ref string

The reference.

endpoint_provider

An handle for an origin or destination API in a feedback migration.

Fields:

Name Description
url string

Return the URL of this endpoint, if any.

endpoint_provider.new_destination_ref

Creates a new destination reference out of this endpoint.

destination_ref endpoint_provider.new_destination_ref(ref, type, url=None)

Parameters:

Parameter Description
ref string

The reference.
type string

The type of this reference.
url string or NoneType

The url associated with this reference, if any.

endpoint_provider.new_origin_ref

Creates a new origin reference out of this endpoint.

origin_ref endpoint_provider.new_origin_ref(ref)

Parameters:

Parameter Description
ref string

The reference.

feedback.context

Gives access to the feedback migration information and utilities. This context is a concrete implementation for feedback migrations.

Fields:

Name Description
action_name string

The name of the current action.
cli_labels dict[string, string]

Access labels that a user passes through flag '--labels'. For example: --labels=foo:value1,bar:value2. Then it can access in this way:cli_labels['foo'].
console Console

Get an instance of the console to report errors or warnings
destination endpoint

An object representing the destination. Can be used to query or modify the destination state
feedback_name string

The name of the Feedback migration calling this action.
origin endpoint

An object representing the origin. Can be used to query about the ref or modifying the origin state
params dict

Parameters for the function if created with core.action
refs sequence of string

A list containing string representations of the entities that triggered the event

feedback.context.error

Returns an error action result.

dynamic.action_result feedback.context.error(msg)

Parameters:

Parameter Description
msg string

The error message

feedback.context.noop

Returns a no op action result with an optional message.

dynamic.action_result feedback.context.noop(msg=None)

Parameters:

Parameter Description
msg string or NoneType

The no op message

feedback.context.record_effect

Records an effect of the current action.

feedback.context.record_effect(summary, origin_refs, destination_ref, errors=[], type="UPDATED")

Parameters:

Parameter Description
summary string

The summary of this effect
origin_refs sequence of origin_ref

The origin refs
destination_ref destination_ref

The destination ref
errors sequence of string

An optional list of errors
type string

The type of migration effect:

  • 'CREATED': A new review or change was created.
  • 'UPDATED': An existing review or change was updated.
  • 'NOOP': The change was a noop.
  • 'NOOP_AGAINST_PENDING_CHANGE': The change was a noop, relativeto an existing pending change.
  • 'INSUFFICIENT_APPROVALS': The effect couldn't happen because the change doesn't have enough approvals.
  • 'ERROR': A user attributable error happened that prevented the destination from creating/updating the change.
  • 'STARTED': The initial effect of a migration that depends on a previous one. This allows to have 'dependant' migrations defined by users.
    An example of this: a workflow migrates code from a Gerrit review to a GitHub PR, and a feedback migration migrates the test results from a CI in GitHub back to the Gerrit change.
    This effect would be created on the former one.

feedback.context.success

Returns a successful action result.

dynamic.action_result feedback.context.success()

feedback.finish_hook_context

Gives access to the feedback migration information and utilities. This context is a concrete implementation for 'after_migration' hooks.

Fields:

Name Description
action_name string

The name of the current action.
cli_labels dict[string, string]

Access labels that a user passes through flag '--labels'. For example: --labels=foo:value1,bar:value2. Then it can access in this way:cli_labels['foo'].
console Console

Get an instance of the console to report errors or warnings
destination endpoint

An object representing the destination. Can be used to query or modify the destination state
effects sequence of destination_effect

The list of effects that happened in the destination
origin endpoint

An object representing the origin. Can be used to query about the ref or modifying the origin state
params dict

Parameters for the function if created with core.action
revision feedback.revision_context

Get the requested/resolved revision

feedback.finish_hook_context.error

Returns an error action result.

dynamic.action_result feedback.finish_hook_context.error(msg)

Parameters:

Parameter Description
msg string

The error message

feedback.finish_hook_context.noop

Returns a no op action result with an optional message.

dynamic.action_result feedback.finish_hook_context.noop(msg=None)

Parameters:

Parameter Description
msg string or NoneType

The no op message

feedback.finish_hook_context.record_effect

Records an effect of the current action.

feedback.finish_hook_context.record_effect(summary, origin_refs, destination_ref, errors=[], type="UPDATED")

Parameters:

Parameter Description
summary string

The summary of this effect
origin_refs sequence of origin_ref

The origin refs
destination_ref destination_ref

The destination ref
errors sequence of string

An optional list of errors
type string

The type of migration effect:

  • 'CREATED': A new review or change was created.
  • 'UPDATED': An existing review or change was updated.
  • 'NOOP': The change was a noop.
  • 'NOOP_AGAINST_PENDING_CHANGE': The change was a noop, relativeto an existing pending change.
  • 'INSUFFICIENT_APPROVALS': The effect couldn't happen because the change doesn't have enough approvals.
  • 'ERROR': A user attributable error happened that prevented the destination from creating/updating the change.
  • 'STARTED': The initial effect of a migration that depends on a previous one. This allows to have 'dependant' migrations defined by users.
    An example of this: a workflow migrates code from a Gerrit review to a GitHub PR, and a feedback migration migrates the test results from a CI in GitHub back to the Gerrit change.
    This effect would be created on the former one.

feedback.finish_hook_context.success

Returns a successful action result.

dynamic.action_result feedback.finish_hook_context.success()

feedback.revision_context

Information about the revision request/resolved for the migration

Fields:

Name Description
labels dict[string, sequence of string]

A dictionary with the labels detected for the requested/resolved revision.

filter_replace

A core.filter_replace transformation

folder

Module for dealing with local filesystem folders

folder.destination

A folder destination is a destination that puts the output in a folder. It can be used both for testing or real production migrations.Given that folder destination does not support a lot of the features of real VCS, there are some limitations on how to use it:

  • It requires passing a ref as an argument, as there is no way of calculating previous migrated changes. Alternatively, --last-rev can be used, which could migrate N changes.
  • Most likely, the workflow should use 'SQUASH' mode, as history is not supported.
  • If 'ITERATIVE' mode is used, a new temp directory will be created for each change migrated.

destination folder.destination()

Command line flags:

Name Type Description
--folder-dir string Local directory to write the output of the migration to. If the directory exists, all files will be deleted. By default Copybara will generate a temporary directory, so you shouldn't need this.

folder.origin

A folder origin is a origin that uses a folder as input. The folder is specified via the source_ref argument.

origin folder.origin(materialize_outside_symlinks=False)

Parameters:

Parameter Description
materialize_outside_symlinks bool

By default folder.origin will refuse any symlink in the migration folder that is an absolute symlink or that refers to a file outside of the folder. If this flag is set, it will materialize those symlinks as regular files in the checkout directory.

Command line flags:

Name Type Description
--folder-origin-author string Deprecated. Please use '--force-author'. Author of the change being migrated from folder.origin()
--folder-origin-ignore-invalid-symlinks boolean If an invalid symlink is found, ignore it instead of failing
--folder-origin-message string Deprecated. Please use '--force-message'. Message of the change being migrated from folder.origin()

format

Module for formatting the code to Google's style/guidelines

format.buildifier

Formats the BUILD files using buildifier.

transformation format.buildifier(paths=glob(["**.bzl", "**/BUILD", "BUILD"]), type='auto', lint="OFF", lint_warnings=[])

Parameters:

Parameter Description
paths glob or NoneType

Paths of the files to format relative to the workdir.
type string or NoneType

The type of the files. Can be 'auto', 'bzl', 'build' or 'workspace'. Note that this is not recommended to be set and might break in the future. The default is 'auto'. This mode formats as BUILD files "BUILD", "BUILD.bazel", "WORKSPACE" and "WORKSPACE.bazel" files. The rest as bzl files. Prefer to use those names for BUILD files instead of setting this flag.
lint string or NoneType

If buildifier --lint should be used. This fixes several common issues. Note that this transformation is difficult to revert. For example if it removes a load statement because is not used after removing a rule, then the reverse workflow needs to add back the load statement (core.replace or similar). Possible values: OFF, FIX. Default is OFF
lint_warnings sequence of string

Warnings used in the lint mode. Default is buildifier default`

Examples:

Default usage:

The default parameters formats all BUILD and bzl files in the checkout directory:

format.buildifier()
Enable lint:

Enable lint for buildifier

format.buildifier(lint = "FIX")
Using globs:

Globs can be used to match only certain files:

format.buildifier(
    paths = glob(["foo/BUILD", "foo/**/BUILD"], exclude = ["foo/bar/BUILD"])
)

Formats all the BUILD files inside foo except for foo/bar/BUILD

Command line flags:

Name Type Description
--buildifier-batch-size int Process files in batches this size

gerrit_api_obj

Gerrit API endpoint implementation for feedback migrations and after migration hooks.

Fields:

Name Description
url string

Return the URL of this endpoint.

gerrit_api_obj.delete_vote

Delete a label vote from an account owner on a Gerrit change.

gerrit_api_obj.delete_vote(change_id, account_id, label_id)

Parameters:

Parameter Description
change_id string

The Gerrit change id.
account_id string

The account owner who votes on label_id. Use 'me' or 'self' if the account owner makes this api call
label_id string

The name of the label.

gerrit_api_obj.get_actions

Retrieve the actions of a Gerrit change.

dict[string, gerritapi.getActionInfo] gerrit_api_obj.get_actions(id, revision)

Parameters:

Parameter Description
id string

The change id or change number.
revision string

The revision of the change.

gerrit_api_obj.get_change

Retrieve a Gerrit change.

gerritapi.ChangeInfo gerrit_api_obj.get_change(id, include_results=['LABELS'])

Parameters:

Parameter Description
id string

The change id or change number.
include_results sequence of string

What to include in the response. See https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#query-options

gerrit_api_obj.list_changes

Get changes from Gerrit based on a query. See https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#list-changes.

sequence of gerritapi.ChangeInfo gerrit_api_obj.list_changes(query, include_results=[])

Parameters:

Parameter Description
query string

The query string to list changes by. See https://gerrit-review.googlesource.com/Documentation/user-search.html#_basic_change_search.
include_results sequence of string

What to include in the response. See https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#query-options

gerrit_api_obj.new_destination_ref

Creates a new destination reference out of this endpoint.

destination_ref gerrit_api_obj.new_destination_ref(ref, type, url=None)

Parameters:

Parameter Description
ref string

The reference.
type string

The type of this reference.
url string or NoneType

The url associated with this reference, if any.

gerrit_api_obj.new_origin_ref

Creates a new origin reference out of this endpoint.

origin_ref gerrit_api_obj.new_origin_ref(ref)

Parameters:

Parameter Description
ref string

The reference.

gerrit_api_obj.post_review

Post a review to a Gerrit change for a particular revision. The review will be authored by the user running the tool, or the role account if running in the service.

gerritapi.ReviewResult gerrit_api_obj.post_review(change_id, revision_id, review_input)

Parameters:

Parameter Description
change_id string

The Gerrit change id.
revision_id string

The revision for which the comment will be posted.
review_input SetReviewInput

The review to post to Gerrit.

gerritapi.AccountInfo

Gerrit account information.

Fields:

Name Description
account_id string

The numeric ID of the account.
email string

The email address the user prefers to be contacted through.
Only set if detailed account information is requested.
See option DETAILED_ACCOUNTS for change queries
and options DETAILS and ALL_EMAILS for account queries.
name string

The full name of the user.
Only set if detailed account information is requested.
See option DETAILED_ACCOUNTS for change queries
and option DETAILS for account queries.
secondary_emails sequence of string

A list of the secondary email addresses of the user.
Only set for account queries when the ALL_EMAILS option or the suggest parameter is set.
Secondary emails are only included if the calling user has the Modify Account, and hence is allowed to see secondary emails of other users.
username string

The username of the user.
Only set if detailed account information is requested.
See option DETAILED_ACCOUNTS for change queries
and option DETAILS for account queries.

gerritapi.ApprovalInfo

Gerrit approval information.

Fields:

Name Description
account_id string

The numeric ID of the account.
date string

The time and date describing when the approval was made.
email string

The email address the user prefers to be contacted through.
Only set if detailed account information is requested.
See option DETAILED_ACCOUNTS for change queries
and options DETAILS and ALL_EMAILS for account queries.
name string

The full name of the user.
Only set if detailed account information is requested.
See option DETAILED_ACCOUNTS for change queries
and option DETAILS for account queries.
secondary_emails sequence of string

A list of the secondary email addresses of the user.
Only set for account queries when the ALL_EMAILS option or the suggest parameter is set.
Secondary emails are only included if the calling user has the Modify Account, and hence is allowed to see secondary emails of other users.
username string

The username of the user.
Only set if detailed account information is requested.
See option DETAILED_ACCOUNTS for change queries
and option DETAILS for account queries.
value int

The vote that the user has given for the label. If present and zero, the user is permitted to vote on the label. If absent, the user is not permitted to vote on that label.

gerritapi.ChangeInfo

Gerrit change information.

Fields:

Name Description
branch string

The name of the target branch.
The refs/heads/ prefix is omitted.
change_id string

The Change-Id of the change.
created string

The timestamp of when the change was created.
current_revision string

The commit ID of the current patch set of this change.
Only set if the current revision is requested or if all revisions are requested.
id string

The ID of the change in the format "<project>~<branch>~<Change-Id>", where 'project', 'branch' and 'Change-Id' are URL encoded. For 'branch' the refs/heads/ prefix is omitted.
labels dict[string, gerritapi.LabelInfo]

The labels of the change as a map that maps the label names to LabelInfo entries.
Only set if labels or detailed labels are requested.
messages sequence of gerritapi.ChangeMessageInfo

Messages associated with the change as a list of ChangeMessageInfo entities.
Only set if messages are requested.
number string

The legacy numeric ID of the change.
owner gerritapi.AccountInfo

The owner of the change as an AccountInfo entity.
project string

The name of the project.
revisions dict[string, gerritapi.RevisionInfo]

All patch sets of this change as a map that maps the commit ID of the patch set to a RevisionInfo entity.
Only set if the current revision is requested (in which case it will only contain a key for the current revision) or if all revisions are requested.
status string

The status of the change (NEW, MERGED, ABANDONED).
subject string

The subject of the change (header line of the commit message).
submittable bool

Whether the change has been approved by the project submit rules. Only set if requested via additional field SUBMITTABLE.
submitted string

The timestamp of when the change was submitted.
topic string

The topic to which this change belongs.
updated string

The timestamp of when the change was last updated.

gerritapi.ChangeMessageInfo

Gerrit change message information.

Fields:

Name Description
author gerritapi.AccountInfo

Author of the message as an AccountInfo entity.
Unset if written by the Gerrit system.
date string

The timestamp of when this identity was constructed.
id string

The ID of the message.
message string

The text left by the user.
real_author gerritapi.AccountInfo

Real author of the message as an AccountInfo entity.
Set if the message was posted on behalf of another user.
revision_number int

Which patchset (if any) generated this message.
tag string

Value of the tag field from ReviewInput set while posting the review. NOTE: To apply different tags on on different votes/comments multiple invocations of the REST call are required.

gerritapi.ChangesQuery

Input for listing Gerrit changes. See https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#list-changes

gerritapi.CommitInfo

Gerrit commit information.

Fields:

Name Description
author gerritapi.GitPersonInfo

The author of the commit as a GitPersonInfo entity.
commit string

The commit ID. Not set if included in a RevisionInfo entity that is contained in a map which has the commit ID as key.
committer gerritapi.GitPersonInfo

The committer of the commit as a GitPersonInfo entity.
message string

The commit message.
parents sequence of gerritapi.ParentCommitInfo

The parent commits of this commit as a list of CommitInfo entities. In each parent only the commit and subject fields are populated.
subject string

The subject of the commit (header line of the commit message).

gerritapi.getActionInfo

Gerrit actions information.

Fields:

Name Description
enabled bool

If true the action is permitted at this time and the caller is likely allowed to execute it.
label string

Short title to display to a user describing the action

gerritapi.GitPersonInfo

Git person information.

Fields:

Name Description
date string

The timestamp of when this identity was constructed.
email string

The email address of the author/committer.
name string

The name of the author/committer.

gerritapi.LabelInfo

Gerrit label information.

Fields:

Name Description
all sequence of gerritapi.ApprovalInfo

List of all approvals for this label as a list of ApprovalInfo entities. Items in this list may not represent actual votes cast by users; if a user votes on any label, a corresponding ApprovalInfo will appear in this list for all labels.
approved gerritapi.AccountInfo

One user who approved this label on the change (voted the maximum value) as an AccountInfo entity.
blocking bool

If true, the label blocks submit operation. If not set, the default is false.
default_value int

The default voting value for the label. This value may be outside the range specified in permitted_labels.
disliked gerritapi.AccountInfo

One user who disliked this label on the change (voted negatively, but not the minimum value) as an AccountInfo entity.
recommended gerritapi.AccountInfo

One user who recommended this label on the change (voted positively, but not the maximum value) as an AccountInfo entity.
rejected gerritapi.AccountInfo

One user who rejected this label on the change (voted the minimum value) as an AccountInfo entity.
value int

The voting value of the user who recommended/disliked this label on the change if it is not "+1"/"-1".
values dict[string, string]

A map of all values that are allowed for this label. The map maps the values ("-2", "-1", "0", "+1", "+2") to the value descriptions.

gerritapi.ParentCommitInfo

Gerrit parent commit information.

Fields:

Name Description
commit string

The commit ID. Not set if included in a RevisionInfo entity that is contained in a map which has the commit ID as key.
subject string

The subject of the commit (header line of the commit message).

gerritapi.ReviewResult

Gerrit review result.

Fields:

Name Description
labels dict[string, int]

Map of labels to values after the review was posted.
ready bool

If true, the change was moved from WIP to ready for review as a result of this action. Not set if false.

gerritapi.RevisionInfo

Gerrit revision information.

Fields:

Name Description
commit gerritapi.CommitInfo

The commit of the patch set as CommitInfo entity.
created string

The timestamp of when the patch set was created.
kind string

The change kind. Valid values are REWORK, TRIVIAL_REBASE, MERGE_FIRST_PARENT_UPDATE, NO_CODE_CHANGE, and NO_CHANGE.
patchset_number int

The patch set number, or edit if the patch set is an edit.
ref string

The Git reference for the patch set.
uploader gerritapi.AccountInfo

The uploader of the patch set as an AccountInfo entity.

git

Set of functions to define Git origins and destinations.

Command line flags:

Name Type Description
--experiment-checkout-affected-files boolean If set, copybara will only checkout affected files at git origin. Note that this is experimental.
--git-credential-helper-store-file string Credentials store file to be used. See https://git-scm.com/docs/git-credential-store
--git-no-verify boolean Pass the '--no-verify' option to git pushes and commits to disable git commit hooks.
--git-tag-overwrite boolean If set, copybara will force update existing git tag
--nogit-credential-helper-store boolean Disable using credentials store. See https://git-scm.com/docs/git-credential-store
--nogit-prompt boolean Disable username/password prompt and fail if no credentials are found. This flag sets the environment variable GIT_TERMINAL_PROMPT which is intended for automated jobs running Git https://git-scm.com/docs/git/2.3.0#git-emGITTERMINALPROMPTem

git.destination

Creates a commit in a git repository using the transformed worktree.

For GitHub use git.github_destination. For creating Pull Requests in GitHub, use git.github_pr_destination. For creating a Gerrit change use git.gerrit_destination.

Given that Copybara doesn't ask for user/password in the console when doing the push to remote repos, you have to use ssh protocol, have the credentials cached or use a credential manager.

destination git.destination(url, push='master', tag_name=None, tag_msg=None, fetch=None, partial_fetch=False, integrates=None, primary_branch_migration=False, checker=None)

Parameters:

Parameter Description
url string

Indicates the URL to push to as well as the URL from which to get the parent commit
push string

Reference to use for pushing the change, for example 'main'.
tag_name string or NoneType

A template string that refers to a tag name. If tag_name exists, overwrite this tag only if flag git-tag-overwrite is set. Note that tag creation is best-effort and migration will succeed even if the tag cannot be created. Usage: Users can use a string or a string with a label. For instance ${label}_tag_name. And the value of label must be in changes' label list. Otherwise, tag won't be created.
tag_msg string or NoneType

A template string that refers to the commit msg of a tag. If set, we will create an annotated tag when tag_name is set. Usage: Users can use a string or a string with a label. For instance ${label}_message. And the value of label must be in changes' label list. Otherwise, tag will be created with sha1's commit msg.
fetch string or NoneType

Indicates the ref from which to get the parent commit. Defaults to push value if None
partial_fetch bool

This is an experimental feature that only works for certain origin globs.
integrates sequence of git_integrate or NoneType

Integrate changes from a url present in the migrated change label. Defaults to a semi-fake merge if COPYBARA_INTEGRATE_REVIEW label is present in the message
primary_branch_migration bool

When enabled, copybara will ignore the 'push' and 'fetch' params if either is 'master' or 'main' and instead try to establish the default git branch. If this fails, it will fall back to the param's declared value.
This is intended to help migrating to the new standard of using 'main' without breaking users relying on the legacy default.
checker checker or NoneType

A checker that can check leaks or other checks in the commit created.

Command line flags:

Name Type Description
--git-committer-email string If set, overrides the committer e-mail for the generated commits in git destination.
--git-committer-name string If set, overrides the committer name for the generated commits in git destination.
--git-destination-fetch string If set, overrides the git destination fetch reference.
--git-destination-ignore-integration-errors boolean If an integration error occurs, ignore it and continue without the integrate
--git-destination-last-rev-first-parent boolean Use git --first-parent flag when looking for last-rev in previous commits
--git-destination-non-fast-forward boolean Allow non-fast-forward pushes to the destination. We only allow this when used with different push != fetch references.
--git-destination-path string If set, the tool will use this directory for the local repository. Note that if the directory exists it needs to be a git repository. Copybara will revert any staged/unstaged changes. For example, you can override destination url with a local non-bare repo (or existing empty folder) with this flag.
--git-destination-push string If set, overrides the git destination push reference.
--git-destination-url string If set, overrides the git destination URL.
--git-skip-checker boolean If true and git.destination has a configured checker, it will not be used in the migration.
--nogit-destination-rebase boolean Don't rebase the change automatically for workflows CHANGE_REQUEST mode

git.gerrit_api

Defines a feedback API endpoint for Gerrit, that exposes relevant Gerrit API operations.

endpoint_provider git.gerrit_api(url, checker=None)

Parameters:

Parameter Description
url string

Indicates the Gerrit repo URL.
checker checker or NoneType

A checker for the Gerrit API transport.

Command line flags:

Name Type Description
--gerrit-change-id string ChangeId to use in the generated commit message. Use this flag if you want to reuse the same Gerrit review for an export.
--gerrit-new-change boolean Create a new change instead of trying to reuse an existing one.
--gerrit-topic string Gerrit topic to use

git.gerrit_destination

Creates a change in Gerrit using the transformed worktree. If this is used in iterative mode, then each commit pushed in a single Copybara invocation will have the correct commit parent. The reviews generated can then be easily done in the correct order without rebasing.

destination git.gerrit_destination(url, fetch, push_to_refs_for=fetch value, submit=False, partial_fetch=False, notify=None, change_id_policy='FAIL_IF_PRESENT', allow_empty_diff_patchset=True, reviewers=[], cc=[], labels=[], api_checker=None, integrates=None, topic=None, gerrit_submit=False, primary_branch_migration=False, checker=None)

Parameters:

Parameter Description
url string

Indicates the URL to push to as well as the URL from which to get the parent commit
fetch string

Indicates the ref from which to get the parent commit
push_to_refs_for string or NoneType

Review branch to push the change to, for example setting this to 'feature_x' causes the destination to push to 'refs/for/feature_x'. It defaults to 'fetch' value.
submit bool

If true, skip the push thru Gerrit refs/for/branch and directly push to branch. This is effectively a git.destination that sets a Change-Id
partial_fetch bool

This is an experimental feature that only works for certain origin globs.
notify string or NoneType

Type of Gerrit notify option (https://gerrit-review.googlesource.com/Documentation/user-upload.html#notify). Sends notifications by default.
change_id_policy string

What to do in the presence or absent of Change-Id in message:

  • 'REQUIRE': Require that the change_id is present in the message as a valid label
  • 'FAIL_IF_PRESENT': Fail if found in message
  • 'REUSE': Reuse if present. Otherwise generate a new one
  • 'REPLACE': Replace with a new one if found
allow_empty_diff_patchset bool

By default Copybara will upload a new PatchSet to Gerrit without checking the previous one. If this set to false, Copybara will download current PatchSet and check the diff against the new diff.
reviewers sequence

The list of the reviewers will be added to gerrit change reviewer listThe element in the list is: an email, for example: "foo@example.com" or label for example: ${SOME_GERRIT_REVIEWER}. These are under the condition of assuming that users have registered to gerrit repos
cc sequence

The list of the email addresses or users that will be CCed in the review. Can use labels as the reviewers field.
labels sequence

The list of labels to be pushed with the change. The format is the label along with the associated value. For example: Run-Presubmit+1
api_checker checker or NoneType

A checker for the Gerrit API endpoint provided for after_migration hooks. This field is not required if the workflow hooks don't use the origin/destination endpoints.
integrates sequence of git_integrate or NoneType

Integrate changes from a url present in the migrated change label. Defaults to a semi-fake merge if COPYBARA_INTEGRATE_REVIEW label is present in the message
topic string or NoneType

Sets the topic of the Gerrit change created.

By default it sets no topic. This field accepts a template with labels. For example: "topic_${CONTEXT_REFERENCE}"
gerrit_submit bool

By default, Copybara uses git commit/push to the main branch when submit = True. If this flag is enabled, it will update the Gerrit change with the latest commit and submit using Gerrit.
primary_branch_migration bool

When enabled, copybara will ignore the 'push_to_refs_for' and 'fetch' params if either is 'master' or 'main' and instead try to establish the default git branch. If this fails, it will fall back to the param's declared value.
This is intended to help migrating to the new standard of using 'main' without breaking users relying on the legacy default.
checker checker or NoneType

A checker that validates the commit files & message. If api_checker is not set, it will also be used for checking API calls. If only api_checkeris used, that checker will only apply to API calls.

Command line flags:

Name Type Description
--git-committer-email string If set, overrides the committer e-mail for the generated commits in git destination.
--git-committer-name string If set, overrides the committer name for the generated commits in git destination.
--git-destination-fetch string If set, overrides the git destination fetch reference.
--git-destination-ignore-integration-errors boolean If an integration error occurs, ignore it and continue without the integrate
--git-destination-last-rev-first-parent boolean Use git --first-parent flag when looking for last-rev in previous commits
--git-destination-non-fast-forward boolean Allow non-fast-forward pushes to the destination. We only allow this when used with different push != fetch references.
--git-destination-path string If set, the tool will use this directory for the local repository. Note that if the directory exists it needs to be a git repository. Copybara will revert any staged/unstaged changes. For example, you can override destination url with a local non-bare repo (or existing empty folder) with this flag.
--git-destination-push string If set, overrides the git destination push reference.
--git-destination-url string If set, overrides the git destination URL.
--git-skip-checker boolean If true and git.destination has a configured checker, it will not be used in the migration.
--nogit-destination-rebase boolean Don't rebase the change automatically for workflows CHANGE_REQUEST mode

git.gerrit_origin

Defines a Git origin for Gerrit reviews.

Implicit labels that can be used/exposed:

  • GERRIT_CHANGE_NUMBER: The change number for the Gerrit review.
  • GERRIT_CHANGE_ID: The change id for the Gerrit review.
  • GERRIT_CHANGE_DESCRIPTION: The description of the Gerrit review.
  • COPYBARA_INTEGRATE_REVIEW: A label that when exposed, can be used to integrate automatically in the reverse workflow.
  • GERRIT_CHANGE_BRANCH: The destination branch for thechange
  • GERRIT_CHANGE_TOPIC: The change topic
  • GERRIT_COMPLETE_CHANGE_ID: Complete Change-Id with project, branch and Change-Id
  • GERRIT_OWNER_EMAIL: Owner email
  • GERRIT_REVIEWER_EMAIL: Multiple value field with the email of the reviewers
  • GERRIT_CC_EMAIL: Multiple value field with the email of the people/groups in cc

origin git.gerrit_origin(url, ref=None, submodules='NO', first_parent=True, partial_fetch=False, api_checker=None, patch=None, branch=None, describe_version=None, ignore_gerrit_noop=False, primary_branch_migration=False)

Parameters:

Parameter Description
url string

Indicates the URL of the git repository
ref string or NoneType

DEPRECATED. Use git.origin for submitted branches.
submodules string

Download submodules. Valid values: NO, YES, RECURSIVE.
first_parent bool

If true, it only uses the first parent when looking for changes. Note that when disabled in ITERATIVE mode, it will try to do a migration for each change of the merged branch.
partial_fetch bool

If true, partially fetch git repository by only fetching affected files..
api_checker checker or NoneType

A checker for the Gerrit API endpoint provided for after_migration hooks. This field is not required if the workflow hooks don't use the origin/destination endpoints.
patch transformation or NoneType

Patch the checkout dir. The difference with patch.apply transformation is that here we can apply it using three-way
branch string or NoneType

Limit the import to changes that are for this branch. By default imports everything.
describe_version bool or NoneType

Download tags and use 'git describe' to create two labels with a meaningful version:

- GIT_DESCRIBE_CHANGE_VERSION: The version for the change or changes being migrated. The value changes per change in ITERATIVE mode and will be the latest migrated change in SQUASH (In other words, doesn't include excluded changes). this is normally what users want to use.
- GIT_DESCRIBE_REQUESTED_VERSION: git describe for the requested/head version. Constant in ITERATIVE mode and includes filtered changes.
GIT_DESCRIBE_FIRST_PARENT: git describe for the first parent version.
ignore_gerrit_noop bool

Option to not migrate Gerrit changes that do not change origin_files
primary_branch_migration bool

When enabled, copybara will ignore the 'ref' param if it is 'master' or 'main' and instead try to establish the default git branch. If this fails, it will fall back to the 'ref' param.
This is intended to help migrating to the new standard of using 'main' without breaking users relying on the legacy default.

git.gerrit_trigger

Defines a feedback trigger based on updates on a Gerrit change.

trigger git.gerrit_trigger(url, checker=None, events=[])

Parameters:

Parameter Description
url string

Indicates the Gerrit repo URL.
checker checker or NoneType

A checker for the Gerrit API transport provided by this trigger.
events sequence of string or dict of sequence or NoneType

Types of events to monitor. Optional. Can either be a list of event types or a dict of event types to particular events of that type, e.g. ['LABELS'] or {'LABELS': 'my_label_name'}.
Valid values for event types are: 'LABELS'

Command line flags:

Name Type Description
--gerrit-change-id string ChangeId to use in the generated commit message. Use this flag if you want to reuse the same Gerrit review for an export.
--gerrit-new-change boolean Create a new change instead of trying to reuse an existing one.
--gerrit-topic string Gerrit topic to use

git.github_api

Defines a feedback API endpoint for GitHub, that exposes relevant GitHub API operations.

endpoint_provider git.github_api(url, checker=None)

Parameters:

Parameter Description
url string

Indicates the GitHub repo URL.
checker checker or NoneType

A checker for the GitHub API transport.

Command line flags:

Name Type Description
--github-destination-delete-pr-branch boolean Overwrite git.github_destination delete_pr_branch field

git.github_destination

Creates a commit in a GitHub repository branch (for example master). For creating PullRequest use git.github_pr_destination.

destination git.github_destination(url, push='master', fetch=None, pr_branch_to_update=None, partial_fetch=False, delete_pr_branch=False, integrates=None, api_checker=None, primary_branch_migration=False, tag_name=None, tag_msg=None, checker=None)

Parameters:

Parameter Description
url string

Indicates the URL to push to as well as the URL from which to get the parent commit
push string

Reference to use for pushing the change, for example 'main'.
fetch string or NoneType

Indicates the ref from which to get the parent commit. Defaults to push value if None
pr_branch_to_update string or NoneType

A template string that refers to a pull request branch in the same repository will be updated to current commit of this push branch only if pr_branch_to_update exists. The reason behind this field is that presubmiting changes creates and leaves a pull request open. By using this, we can automerge/close this type of pull requests. As a result, users will see this pr_branch_to_update as merged to this push branch. Usage: Users can use a string or a string with a label. For instance ${label}_pr_branch_name. And the value of label must be in changes' label list. Otherwise, nothing will happen.
partial_fetch bool

This is an experimental feature that only works for certain origin globs.
delete_pr_branch bool or NoneType

When pr_branch_to_update is enabled, it will delete the branch reference after the push to the branch and main branch (i.e master) happens. This allows to cleanup temporary branches created for testing.
integrates sequence of git_integrate or NoneType

Integrate changes from a url present in the migrated change label. Defaults to a semi-fake merge if COPYBARA_INTEGRATE_REVIEW label is present in the message
api_checker checker or NoneType

A checker for the Gerrit API endpoint provided for after_migration hooks. This field is not required if the workflow hooks don't use the origin/destination endpoints.
primary_branch_migration bool

When enabled, copybara will ignore the 'push' and 'fetch' params if either is 'master' or 'main' and instead try to establish the default git branch. If this fails, it will fall back to the param's declared value.
This is intended to help migrating to the new standard of using 'main' without breaking users relying on the legacy default.
tag_name string or NoneType

A template string that specifies to a tag name. If the tag already exists, copybara will only overwrite it if the --git-tag-overwrite flag is set.
Note that tag creation is best-effort and the migration will succeed even if the tag cannot be created. Usage: Users can use a string or a string with a label. For instance ${label}_tag_name. And the value of label must be in changes' label list. Otherwise, tag won't be created.
tag_msg string or NoneType

A template string that refers to the commit msg for a tag. If set, copybara willcreate an annotated tag with this custom message
Usage: Labels in the string will be resolved. E.g. .${label}_message.By default, the tag will be created with the labeled commit's message.
checker checker or NoneType

A checker that validates the commit files & message. If api_checker is not set, it will also be used for checking API calls. If only api_checkeris used, that checker will only apply to API calls.

Command line flags:

Name Type Description
--git-committer-email string If set, overrides the committer e-mail for the generated commits in git destination.
--git-committer-name string If set, overrides the committer name for the generated commits in git destination.
--git-destination-fetch string If set, overrides the git destination fetch reference.
--git-destination-ignore-integration-errors boolean If an integration error occurs, ignore it and continue without the integrate
--git-destination-last-rev-first-parent boolean Use git --first-parent flag when looking for last-rev in previous commits
--git-destination-non-fast-forward boolean Allow non-fast-forward pushes to the destination. We only allow this when used with different push != fetch references.
--git-destination-path string If set, the tool will use this directory for the local repository. Note that if the directory exists it needs to be a git repository. Copybara will revert any staged/unstaged changes. For example, you can override destination url with a local non-bare repo (or existing empty folder) with this flag.
--git-destination-push string If set, overrides the git destination push reference.
--git-destination-url string If set, overrides the git destination URL.
--git-skip-checker boolean If true and git.destination has a configured checker, it will not be used in the migration.
--nogit-destination-rebase boolean Don't rebase the change automatically for workflows CHANGE_REQUEST mode

git.github_origin

Defines a Git origin for a Github repository. This origin should be used for public branches. Use github_pr_origin for importing Pull Requests.

origin git.github_origin(url, ref=None, submodules='NO', first_parent=True, partial_fetch=False, patch=None, describe_version=None, version_selector=None, primary_branch_migration=False)

Parameters:

Parameter Description
url string

Indicates the URL of the git repository
ref string or NoneType

Represents the default reference that will be used for reading the revision from the git repository. For example: 'master'
submodules string

Download submodules. Valid values: NO, YES, RECURSIVE.
first_parent bool

If true, it only uses the first parent when looking for changes. Note that when disabled in ITERATIVE mode, it will try to do a migration for each change of the merged branch.
partial_fetch bool

If true, partially fetch git repository by only fetching affected files.
patch transformation or NoneType

Patch the checkout dir. The difference with patch.apply transformation is that here we can apply it using three-way
describe_version bool or NoneType

Download tags and use 'git describe' to create two labels with a meaningful version:

- GIT_DESCRIBE_CHANGE_VERSION: The version for the change or changes being migrated. The value changes per change in ITERATIVE mode and will be the latest migrated change in SQUASH (In other words, doesn't include excluded changes). this is normally what users want to use.
- GIT_DESCRIBE_REQUESTED_VERSION: git describe for the requested/head version. Constant in ITERATIVE mode and includes filtered changes.
GIT_DESCRIBE_FIRST_PARENT: git describe for the first parent version.
version_selector VersionSelector or NoneType

Select a custom version (tag)to migrate instead of 'ref'. Version selector is expected to match the whole refspec (e.g. 'refs/heads/${n1}')
primary_branch_migration bool

When enabled, copybara will ignore the 'ref' param if it is 'master' or 'main' and instead try to establish the default git branch. If this fails, it will fall back to the 'ref' param.
This is intended to help migrating to the new standard of using 'main' without breaking users relying on the legacy default.

git.github_pr_destination

Creates changes in a new pull request in the destination.

destination git.github_pr_destination(url, destination_ref='master', pr_branch=None, partial_fetch=False, allow_empty_diff=True, title=None, body=None, integrates=None, api_checker=None, update_description=False, primary_branch_migration=False, checker=None)

Parameters:

Parameter Description
url string

Url of the GitHub project. For example "https://github.com/google/copybara'"
destination_ref string

Destination reference for the change.
pr_branch string or NoneType

Customize the pull request branch. Any variable present in the message in the form of ${CONTEXT_REFERENCE} will be replaced by the corresponding stable reference (head, PR number, Gerrit change number, etc.).
partial_fetch bool

This is an experimental feature that only works for certain origin globs.
allow_empty_diff bool

By default, copybara migrates changes without checking existing PRs. If set, copybara will skip pushing a change to an existing PR only if the git three of the pending migrating change is the same as the existing PR.
title string or NoneType

When creating (or updating if update_description is set) a pull request, use this title. By default it uses the change first line. This field accepts a template with labels. For example: "Change ${CONTEXT_REFERENCE}"
body string or NoneType

When creating (or updating if update_description is set) a pull request, use this body. By default it uses the change summary. This field accepts a template with labels. For example: "Change ${CONTEXT_REFERENCE}"
integrates sequence of git_integrate or NoneType

Integrate changes from a url present in the migrated change label. Defaults to a semi-fake merge if COPYBARA_INTEGRATE_REVIEW label is present in the message
api_checker checker or NoneType

A checker for the GitHub API endpoint provided for after_migration hooks. This field is not required if the workflow hooks don't use the origin/destination endpoints.
update_description bool

By default, Copybara only set the title and body of the PR when creating the PR. If this field is set to true, it will update those fields for every update.
primary_branch_migration bool

When enabled, copybara will ignore the 'desination_ref' param if it is 'master' or 'main' and instead try to establish the default git branch. If this fails, it will fall back to the param's declared value.
This is intended to help migrating to the new standard of using 'main' without breaking users relying on the legacy default.
checker checker or NoneType

A checker that validates the commit files & message. If api_checker is not set, it will also be used for checking API calls. If only api_checkeris used, that checker will only apply to API calls.

Examples:

Common usage:

Create a branch by using copybara's computerIdentity algorithm:

git.github_pr_destination(
        url = "https://github.com/google/copybara",
        destination_ref = "master",
    )
Using pr_branch with label:

Customize pr_branch with context reference:

git.github_pr_destination(
        url = "https://github.com/google/copybara",
         destination_ref = "master",
         pr_branch = 'test_${CONTEXT_REFERENCE}',
    )
Using pr_branch with constant string:

Customize pr_branch with a constant string:

git.github_pr_destination(
        url = "https://github.com/google/copybara",
        destination_ref = "master",
        pr_branch = 'test_my_branch',
    )

Command line flags:

Name Type Description
--git-committer-email string If set, overrides the committer e-mail for the generated commits in git destination.
--git-committer-name string If set, overrides the committer name for the generated commits in git destination.
--git-destination-fetch string If set, overrides the git destination fetch reference.
--git-destination-ignore-integration-errors boolean If an integration error occurs, ignore it and continue without the integrate
--git-destination-last-rev-first-parent boolean Use git --first-parent flag when looking for last-rev in previous commits
--git-destination-non-fast-forward boolean Allow non-fast-forward pushes to the destination. We only allow this when used with different push != fetch references.
--git-destination-path string If set, the tool will use this directory for the local repository. Note that if the directory exists it needs to be a git repository. Copybara will revert any staged/unstaged changes. For example, you can override destination url with a local non-bare repo (or existing empty folder) with this flag.
--git-destination-push string If set, overrides the git destination push reference.
--git-destination-url string If set, overrides the git destination URL.
--git-skip-checker boolean If true and git.destination has a configured checker, it will not be used in the migration.
--github-destination-pr-branch string If set, uses this branch for creating the pull request instead of using a generated one
--github-destination-pr-create boolean If the pull request should be created
--nogit-destination-rebase boolean Don't rebase the change automatically for workflows CHANGE_REQUEST mode

git.github_pr_origin

Defines a Git origin for Github pull requests.

Implicit labels that can be used/exposed:

  • GITHUB_PR_NUMBER: The pull request number if the reference passed was in the form of https://github.com/project/pull/123, refs/pull/123/head or refs/pull/123/master.
  • COPYBARA_INTEGRATE_REVIEW: A label that when exposed, can be used to integrate automatically in the reverse workflow.
  • GITHUB_BASE_BRANCH: The name of the branch which serves as the base for the Pull Request.
  • GITHUB_BASE_BRANCH_SHA1: The SHA-1 of the commit used as baseline. Generally, the baseline commit is the point of divergence between the PR's 'base' and 'head' branches. When use_merge = True is specified, the baseline is instead the tip of the PR's base branch.
  • GITHUB_PR_USE_MERGE: Equal to 'true' if the workflow is importing a GitHub PR 'merge' commit and 'false' when importing a GitHub PR 'head' commit.
  • GITHUB_PR_TITLE: Title of the Pull Request.
  • GITHUB_PR_BODY: Body of the Pull Request.
  • GITHUB_PR_URL: GitHub url of the Pull Request.
  • GITHUB_PR_HEAD_SHA: The SHA-1 of the head commit of the pull request.
  • GITHUB_PR_USER: The login of the author the pull request.
  • GITHUB_PR_ASSIGNEE: A repeated label with the login of the assigned users.
  • GITHUB_PR_REVIEWER_APPROVER: A repeated label with the login of users that have participated in the review and that can approve the import. Only populated if review_state field is set. Every reviewers type matching review_approvers will be added to this list.
  • GITHUB_PR_REVIEWER_OTHER: A repeated label with the login of users that have participated in the review but cannot approve the import. Only populated if review_state field is set.

origin git.github_pr_origin(url, use_merge=False, required_labels=[], required_status_context_names=[], required_check_runs=[], retryable_labels=[], submodules='NO', baseline_from_branch=False, first_parent=True, partial_fetch=False, state='OPEN', review_state=None, review_approvers=["COLLABORATOR", "MEMBER", "OWNER"], api_checker=None, patch=None, branch=None, describe_version=None)

Parameters:

Parameter Description
url string

Indicates the URL of the GitHub repository
use_merge bool

If the content for refs/pull/<ID>/merge should be used instead of the PR head. The GitOrigin-RevId still will be the one from refs/pull/<ID>/head revision.
required_labels sequence of string

Required labels to import the PR. All the labels need to be present in order to migrate the Pull Request.
required_status_context_names sequence of string

A list of names of services which must all mark the PR with 'success' before it can be imported.

See https://docs.github.com/en/rest/reference/repos#statuses
required_check_runs sequence of string

A list of check runs which must all have a value of 'success' in order to import the PR.

See https://docs.github.com/en/rest/guides/getting-started-with-the-checks-api
retryable_labels sequence of string

Required labels to import the PR that should be retried. This parameter must be a subset of required_labels.
submodules string

Download submodules. Valid values: NO, YES, RECURSIVE.
baseline_from_branch bool

WARNING: Use this field only for github -> git CHANGE_REQUEST workflows.
When the field is set to true for CHANGE_REQUEST workflows it will find the baseline comparing the Pull Request with the base branch instead of looking for the *-RevId label in the commit message.
first_parent bool

If true, it only uses the first parent when looking for changes. Note that when disabled in ITERATIVE mode, it will try to do a migration for each change of the merged branch.
partial_fetch bool

This is an experimental feature that only works for certain origin globs.
state string

Only migrate Pull Request with that state. Possible values: 'OPEN', 'CLOSED' or 'ALL'. Default 'OPEN'
review_state string or NoneType

Required state of the reviews associated with the Pull Request Possible values: 'HEAD_COMMIT_APPROVED', 'ANY_COMMIT_APPROVED', 'HAS_REVIEWERS' or 'ANY'. Default None. This field is required if the user wants GITHUB_PR_REVIEWER_APPROVER and GITHUB_PR_REVIEWER_OTHER labels populated
review_approvers sequence of string or NoneType

The set of reviewer types that are considered for approvals. In order to have any effect, review_state needs to be set. GITHUB_PR_REVIEWER_APPROVER` will be populated for these types. See the valid types here: https://developer.github.com/v4/enum/commentauthorassociation/
api_checker checker or NoneType

A checker for the GitHub API endpoint provided for after_migration hooks. This field is not required if the workflow hooks don't use the origin/destination endpoints.
patch transformation or NoneType

Patch the checkout dir. The difference with patch.apply transformation is that here we can apply it using three-way
branch string or NoneType

If set, it will only migrate pull requests for this base branch
describe_version bool or NoneType

Download tags and use 'git describe' to create two labels with a meaningful version:

- GIT_DESCRIBE_CHANGE_VERSION: The version for the change or changes being migrated. The value changes per change in ITERATIVE mode and will be the latest migrated change in SQUASH (In other words, doesn't include excluded changes). this is normally what users want to use.
- GIT_DESCRIBE_REQUESTED_VERSION: git describe for the requested/head version. Constant in ITERATIVE mode and includes filtered changes.
GIT_DESCRIBE_FIRST_PARENT: git describe for the first parent version.

Command line flags:

Name Type Description
--github-force-import boolean Force import regardless of the state of the PR
--github-pr-merge boolean Override merge bit from config
--github-required-check-run list Required check runs in the Pull Request to be imported by github_pr_origin
--github-required-label list Required labels in the Pull Request to be imported by github_pr_origin
--github-required-status-context-name list Required status context names in the Pull Request to be imported by github_pr_origin
--github-retryable-label list Required labels in the Pull Request that should be retryed to be imported by github_pr_origin
--github-skip-required-check-runs boolean Skip checking check runs for importing Pull Requests. Note that this is dangerous as it might import an unsafe PR.
--github-skip-required-labels boolean Skip checking labels for importing Pull Requests. Note that this is dangerous as it might import an unsafe PR.
--github-skip-required-status-context-names boolean Skip checking status context names for importing Pull Requests. Note that this is dangerous as it might import an unsafe PR.

git.github_trigger

Defines a feedback trigger based on updates on a GitHub PR.

trigger git.github_trigger(url, checker=None, events=[])

Parameters:

Parameter Description
url string

Indicates the GitHub repo URL.
checker checker or NoneType

A checker for the GitHub API transport provided by this trigger.
events sequence of string or dict of sequence

Types of events to subscribe. Can either be a list of event types or a dict of event types to particular events of that type, e.g. ['CHECK_RUNS'] or {'CHECK_RUNS': 'my_check_run_name'}.
Valid values for event types are: 'ISSUES', 'ISSUE_COMMENT', 'PULL_REQUEST', 'PULL_REQUEST_REVIEW_COMMENT', 'PUSH', 'STATUS', 'CHECK_RUNS'

Command line flags:

Name Type Description
--github-destination-delete-pr-branch boolean Overwrite git.github_destination delete_pr_branch field

git.integrate

Integrate changes from a url present in the migrated change label.

git_integrate git.integrate(label="COPYBARA_INTEGRATE_REVIEW", strategy="FAKE_MERGE_AND_INCLUDE_FILES", ignore_errors=True)

Parameters:

Parameter Description
label string

The migration label that will contain the url to the change to integrate.
strategy string

How to integrate the change:

  • 'FAKE_MERGE': Add the url revision/reference as parent of the migration change but ignore all the files from the url. The commit message will be a standard merge one but will include the corresponding RevId label
  • 'FAKE_MERGE_AND_INCLUDE_FILES': Same as 'FAKE_MERGE' but any change to files that doesn't match destination_files will be included as part of the merge commit. So it will be a semi fake merge: Fake for destination_files but merge for non destination files.
  • 'INCLUDE_FILES': Same as 'FAKE_MERGE_AND_INCLUDE_FILES' but it it doesn't create a merge but only include changes not matching destination_files
ignore_errors bool

If we should ignore integrate errors and continue the migration without the integrate

Example:

Integrate changes from a review url:

Assuming we have a git.destination defined like this:

git.destination(
        url = "https://example.com/some_git_repo",
        integrates = [git.integrate()],

)

It will look for COPYBARA_INTEGRATE_REVIEW label during the worklow migration. If the label is found, it will fetch the git url and add that change as an additional parent to the migration commit (merge). It will fake-merge any change from the url that matches destination_files but it will include changes not matching it.

git.latest_version

DEPRECATED: Use core.latest_version.

Customize what version of the available branches and tags to pick. By default it ignores the reference passed as parameter. Using --force in the CLI will force to use the reference passed as argument instead.

VersionSelector git.latest_version(refspec_format="refs/tags/${n0}.${n1}.${n2}", refspec_groups={'n0' : '[0-9]+', 'n1' : '[0-9]+', 'n2' : '[0-9]+'})

Parameters:

Parameter Description
refspec_format string

The format of the branch/tag
refspec_groups dict

A set of named regexes that can be used to match part of the versions. Copybara uses re2 syntax. Use the following nomenclature n0, n1, n2 for the version part (will use numeric sorting) or s0, s1, s2 (alphabetic sorting). Note that there can be mixed but the numbers cannot be repeated. In other words n0, s1, n2 is valid but not n0, s0, n1. n0 has more priority than n1. If there are fields where order is not important, use s(N+1) where N ist he latest sorted field. Example {"n0": "[0-9]+", "s1": "[a-z]+"}

git.mirror

Mirror git references between repositories

git.mirror(name, origin, destination, refspecs=['refs/heads/*'], prune=False, partial_fetch=False, description=None, actions=[])

Parameters:

Parameter Description
name string

Migration name
origin string

Indicates the URL of the origin git repository
destination string

Indicates the URL of the destination git repository
refspecs sequence of string

Represents a list of git refspecs to mirror between origin and destination. For example 'refs/heads/:refs/remotes/origin/' will mirror any reference inside refs/heads to refs/remotes/origin.
prune bool

Remove remote refs that don't have a origin counterpart. Prune is ignored if actions are used (Action is in charge of doing the pruning)
partial_fetch bool

This is an experimental feature that only works for certain origin globs.
description string or NoneType

A description of what this migration achieves
actions sequence

Experimental feature. A list of mirror actions to perform, with the following semantics:
- There is no guarantee of the order of execution.
- Actions need to be independent from each other.
- Failure in one action might prevent other actions from executing. --force can be used to continue for 'user' errors like non-fast-forward errors.

Actions will be in charge of doing the fetch, push, rebases, merges,etc.Only fetches/pushes for the declared refspec are allowed

git.origin

Defines a standard Git origin. For Git specific origins use: github_origin or gerrit_origin.

All the origins in this module accept several string formats as reference (When copybara is called in the form of copybara config workflow reference):

  • Branch name: For example master
  • An arbitrary reference: refs/changes/20/50820/1
  • A SHA-1: Note that it has to be reachable from the default refspec
  • A Git repository URL and reference: http://github.com/foo master
  • A GitHub pull request URL: https://github.com/some_project/pull/1784

So for example, Copybara can be invoked for a git.origin in the CLI as:
copybara copy.bara.sky my_workflow https://github.com/some_project/pull/1784
This will use the pull request as the origin URL and reference.

origin git.origin(url, ref=None, submodules='NO', include_branch_commit_logs=False, first_parent=True, partial_fetch=False, patch=None, describe_version=None, version_selector=None, primary_branch_migration=False)

Parameters:

Parameter Description
url string

Indicates the URL of the git repository
ref string or NoneType

Represents the default reference that will be used for reading the revision from the git repository. For example: 'master'
submodules string

Download submodules. Valid values: NO, YES, RECURSIVE.
include_branch_commit_logs bool

Whether to include raw logs of branch commits in the migrated change message.WARNING: This field is deprecated in favor of 'first_parent' one. This setting only affects merge commits.
first_parent bool

If true, it only uses the first parent when looking for changes. Note that when disabled in ITERATIVE mode, it will try to do a migration for each change of the merged branch.
partial_fetch bool

If true, partially fetch git repository by only fetching affected files.
patch transformation or NoneType

Patch the checkout dir. The difference with patch.apply transformation is that here we can apply it using three-way
describe_version bool or NoneType

Download tags and use 'git describe' to create two labels with a meaningful version:

- GIT_DESCRIBE_CHANGE_VERSION: The version for the change or changes being migrated. The value changes per change in ITERATIVE mode and will be the latest migrated change in SQUASH (In other words, doesn't include excluded changes). this is normally what users want to use.
- GIT_DESCRIBE_REQUESTED_VERSION: git describe for the requested/head version. Constant in ITERATIVE mode and includes filtered changes.
GIT_DESCRIBE_FIRST_PARENT: git describe for the first parent version.
version_selector VersionSelector or NoneType

Select a custom version (tag)to migrate instead of 'ref'. Version selector is expected to match the whole refspec (e.g. 'refs/heads/${n1}')
primary_branch_migration bool

When enabled, copybara will ignore the 'ref' param if it is 'master' or 'main' and instead try to establish the default git branch. If this fails, it will fall back to the 'ref' param.
This is intended to help migrating to the new standard of using 'main' without breaking users relying on the legacy default.

git.review_input

Creates a review to be posted on Gerrit.

SetReviewInput git.review_input(labels={}, message=None, tag=None)

Parameters:

Parameter Description
labels dict

The labels to post.
message string or NoneType

The message to be added as review comment.
tag string or NoneType

Tag to be applied to the review, for instance 'autogenerated:copybara'.

Command line flags:

Name Type Description
--gerrit-change-id string ChangeId to use in the generated commit message. Use this flag if you want to reuse the same Gerrit review for an export.
--gerrit-new-change boolean Create a new change instead of trying to reuse an existing one.
--gerrit-topic string Gerrit topic to use

git.mirrorContext

Expose methods to git.mirror actions to perform operations over git repositories

Fields:

Name Description
action_name string

The name of the current action.
cli_labels dict[string, string]

Access labels that a user passes through flag '--labels'. For example: --labels=foo:value1,bar:value2. Then it can access in this way:cli_labels['foo'].
console Console

Get an instance of the console to report errors or warnings
params dict

Parameters for the function if created with core.action
refs sequence

A list containing string representations of the entities that triggered the event

git.mirrorContext.cherry_pick

Cherry-pick one or more commits to a branch

git_merge_result git.mirrorContext.cherry_pick(branch, commits, add_commit_origin_info=True, merge_parent_number=None, allow_empty=False, fast_forward=False)

Parameters:

Parameter Description
branch string
commits sequence of string

Commits to cherry-pick. An expression like foo..bar can be used to cherry-pick several commits. Note that 'HEAD' will refer to the branch HEAD, since cherry-pick requires a checkout of the branch before cherry-picking.
add_commit_origin_info bool

Add information about the origin of the commit (sha-1) to the message of the newcommit
merge_parent_number unknown

Specify the parent number for cherry-picking merge commits
allow_empty bool

Allow empty commits (noop commits)
fast_forward bool

Fast-forward commits if possible

git.mirrorContext.create_branch

Merge one or more commits into a local branch.

git.mirrorContext.create_branch(name, starting_point=None)

Parameters:

Parameter Description
name string
starting_point unknown

git.mirrorContext.destination_fetch

Fetch from the destination a list of refspecs. Note that fetch happens without pruning.

bool git.mirrorContext.destination_fetch(refspec, prune=True)

Parameters:

Parameter Description
refspec sequence of string
prune bool

git.mirrorContext.destination_push

Push to the destination a list of refspecs.

git.mirrorContext.destination_push(refspec, prune=False)

Parameters:

Parameter Description
refspec sequence of string
prune bool

git.mirrorContext.error

Returns an error action result.

dynamic.action_result git.mirrorContext.error(msg)

Parameters:

Parameter Description
msg string

The error message

git.mirrorContext.merge

Merge one or more commits into a local branch.

git_merge_result git.mirrorContext.merge(branch, commits, msg=None, fast_forward="FF")

Parameters:

Parameter Description
branch string
commits sequence of string
msg unknown
fast_forward string

Valid values are FF (default), NO_FF, FF_ONLY.

git.mirrorContext.noop

Returns a no op action result with an optional message.

dynamic.action_result git.mirrorContext.noop(msg=None)

Parameters:

Parameter Description
msg string or NoneType

The no op message

git.mirrorContext.origin_fetch

Fetch from the origin a list of refspecs. Note that fetch happens without pruning.

bool git.mirrorContext.origin_fetch(refspec, prune=True)

Parameters:

Parameter Description
refspec sequence of string
prune bool

git.mirrorContext.rebase

Rebase one or more commits into a local branch.

git_merge_result git.mirrorContext.rebase(upstream, branch, newBase=None, conflict_advice=None)

Parameters:

Parameter Description
upstream string

upstream branch with new changes
branch string

Current branch with specific commits that we want to rebase in top of the new upstream changes
newBase unknown

Move the rebased changes to a new branch (--into parameter in git rebase)
conflict_advice unknown

Additional information on how to solve the issue in case if conflict

git.mirrorContext.record_effect

Records an effect of the current action.

git.mirrorContext.record_effect(summary, origin_refs, destination_ref, errors=[], type="UPDATED")

Parameters:

Parameter Description
summary string

The summary of this effect
origin_refs sequence of origin_ref

The origin refs
destination_ref destination_ref

The destination ref
errors sequence of string

An optional list of errors
type string

The type of migration effect:

  • 'CREATED': A new review or change was created.
  • 'UPDATED': An existing review or change was updated.
  • 'NOOP': The change was a noop.
  • 'NOOP_AGAINST_PENDING_CHANGE': The change was a noop, relativeto an existing pending change.
  • 'INSUFFICIENT_APPROVALS': The effect couldn't happen because the change doesn't have enough approvals.
  • 'ERROR': A user attributable error happened that prevented the destination from creating/updating the change.
  • 'STARTED': The initial effect of a migration that depends on a previous one. This allows to have 'dependant' migrations defined by users.
    An example of this: a workflow migrates code from a Gerrit review to a GitHub PR, and a feedback migration migrates the test results from a CI in GitHub back to the Gerrit change.
    This effect would be created on the former one.

git.mirrorContext.references

Return a map of reference -> sha-1 for local references matching the refspec or all if no refspec is passed.

dict[string, string] git.mirrorContext.references(refspec=[])

Parameters:

Parameter Description
refspec sequence of string

git.mirrorContext.success

Returns a successful action result.

dynamic.action_result git.mirrorContext.success()

git_merge_result

The result returned by git merge when used in Starlark. For example in git.mirror dynamic actions.

Fields:

Name Description
error bool

True if the merge execution resulted in an error. False otherwise
error_msg string

Error message from git if the merge resulted in a conflict/error. Users must check error field before accessing this field.

github_api_obj

GitHub API endpoint implementation for feedback migrations and after migration hooks.

Fields:

Name Description
url string

Return the URL of this endpoint.

github_api_obj.add_label

Add labels to a PR/issue

github_api_obj.add_label(number, labels)

Parameters:

Parameter Description
number int

Pull Request number
labels sequence of string

List of labels to add.

github_api_obj.create_issue

Create a new issue.

Issue github_api_obj.create_issue(title, body, assignees)

Parameters:

Parameter Description
title string

Title of the issue
body string

Body of the issue.
assignees sequence

GitHub users to whom the issue will be assigned.

github_api_obj.create_status

Create or update a status for a commit. Returns the status created.

github_api_status_obj github_api_obj.create_status(sha, state, context, description, target_url=None)

Parameters:

Parameter Description
sha string

The SHA-1 for which we want to create or update the status
state string

The state of the commit status: 'success', 'error', 'pending' or 'failure'
context string

The context for the commit status. Use a value like 'copybara/import_successful' or similar
description string

Description about what happened
target_url string or NoneType

Url with expanded information about the event

github_api_obj.delete_reference

Delete a reference.

github_api_obj.delete_reference(ref)

Parameters:

Parameter Description
ref string

The name of the reference.

github_api_obj.get_authenticated_user

Get autenticated user info, return null if not found

github_api_user_obj github_api_obj.get_authenticated_user()

github_api_obj.get_check_runs

Get the list of check runs for a sha. https://developer.github.com/v3/checks/runs/#check-runs

github_check_runs_obj github_api_obj.get_check_runs(sha)

Parameters:

Parameter Description
sha string

The SHA-1 for which we want to get the check runs

github_api_obj.get_combined_status

Get the combined status for a commit. Returns None if not found.

github_api_combined_status_obj github_api_obj.get_combined_status(ref)

Parameters:

Parameter Description
ref string

The SHA-1 or ref for which we want to get the combined status

github_api_obj.get_commit

Get information for a commit in GitHub. Returns None if not found.

github_api_github_commit_obj github_api_obj.get_commit(ref)

Parameters:

Parameter Description
ref string

The SHA-1 for which we want to get the combined status

github_api_obj.get_pull_request_comment

Get a pull request comment

github_api_pull_request_comment_obj github_api_obj.get_pull_request_comment(comment_id)

Parameters:

Parameter Description
comment_id string

Comment identifier

github_api_obj.get_pull_request_comments

Get all pull request comments

sequence of github_api_pull_request_comment_obj github_api_obj.get_pull_request_comments(number)

Parameters:

Parameter Description
number int

Pull Request number

github_api_obj.get_pull_requests

Get Pull Requests for a repo

sequence of github_api_pull_request_obj github_api_obj.get_pull_requests(head_prefix=None, base_prefix=None, state="OPEN", sort="CREATED", direction="ASC")

Parameters:

Parameter Description
head_prefix string or NoneType

Only return PRs wher the branch name has head_prefix
base_prefix string or NoneType

Only return PRs where the destination branch name has base_prefix
state string

State of the Pull Request. Can be "OPEN", "CLOSED" or "ALL"
sort string

Sort filter for retrieving the Pull Requests. Can be "CREATED", "UPDATED" or "POPULARITY"
direction string

Direction of the filter. Can be "ASC" or "DESC"

github_api_obj.get_reference

Get a reference SHA-1 from GitHub. Returns None if not found.

github_api_ref_obj github_api_obj.get_reference(ref)

Parameters:

Parameter Description
ref string

The name of the reference. For example: "refs/heads/branchName".

github_api_obj.get_references

Get all the reference SHA-1s from GitHub. Note that Copybara only returns a maximum number of 500.

sequence of github_api_ref_obj github_api_obj.get_references()

github_api_obj.new_destination_ref

Creates a new destination reference out of this endpoint.

destination_ref github_api_obj.new_destination_ref(ref, type, url=None)

Parameters:

Parameter Description
ref string

The reference.
type string

The type of this reference.
url string or NoneType

The url associated with this reference, if any.

github_api_obj.new_origin_ref

Creates a new origin reference out of this endpoint.

origin_ref github_api_obj.new_origin_ref(ref)

Parameters:

Parameter Description
ref string

The reference.

github_api_obj.post_issue_comment

Post a comment on a issue.

github_api_obj.post_issue_comment(number, comment)

Parameters:

Parameter Description
number int

Issue or Pull Request number
comment string

Comment body to post.

github_api_obj.update_pull_request

Update Pull Requests for a repo. Returns None if not found

github_api_pull_request_obj github_api_obj.update_pull_request(number, title=None, body=None, state=None)

Parameters:

Parameter Description
number int

Pull Request number
title string or NoneType

New Pull Request title
body string or NoneType

New Pull Request body
state string or NoneType

State of the Pull Request. Can be "OPEN", "CLOSED"

github_api_obj.update_reference

Update a reference to point to a new commit. Returns the info of the reference.

github_api_ref_obj github_api_obj.update_reference(ref, sha, force)

Parameters:

Parameter Description
ref string

The name of the reference.
sha string

The id for the commit status.
force bool

Indicates whether to force the update or to make sure the update is a fast-forward update. Leaving this out or setting it to false will make sure you're not overwriting work. Default: false

glob

A glob represents a set of relative filepaths in the Copybara workdir.

Globals

Global functions available in Copybara

glob

Returns an object which matches every file in the workdir that matches at least one pattern in include and does not match any of the patterns in exclude.

glob glob(include, exclude=[])

Parameters:

Parameter Description
include sequence of string

The list of glob patterns to include
exclude sequence of string

The list of glob patterns to exclude

Examples:

Simple usage:

Include all the files under a folder except for internal folder files:

glob(["foo/**"], exclude = ["foo/internal/**"])
Multiple folders:

Globs can have multiple inclusive rules:

glob(["foo/**", "bar/**", "baz/**.java"])

This will include all files inside foo and bar folders and Java files inside baz folder.

Multiple excludes:

Globs can have multiple exclusive rules:

glob(["foo/**"], exclude = ["foo/internal/**", "foo/confidential/**" ])

Include all the files of foo except the ones in internal and confidential folders

All BUILD files recursively:

Copybara uses Java globbing. The globbing is very similar to Bash one. This means that recursive globbing for a filename is a bit more tricky:

glob(["BUILD", "**/BUILD"])

This is the correct way of matching all BUILD files recursively, including the one in the root. **/BUILD would only match BUILD files in subdirectories.

Matching multiple strings with one expression:

While two globs can be used for matching two directories, there is a more compact approach:

glob(["{java,javatests}/**"])

This matches any file in java and javatests folders.

Glob union:

This is useful when you want to exclude a broad subset of files but you want to still include some of those files.

glob(["folder/**"], exclude = ["folder/**.excluded"]) + glob(['folder/includeme.excluded'])

This matches all the files in folder, excludes all files in that folder that ends with .excluded but keeps folder/includeme.excluded

+ operator for globs is equivalent to OR operation.

Glob difference:

This is another way to exclude a broad subset of files, but still include some of those files.

glob(["folder/**"]) - glob(["folder/**.excluded"], exclude=["folder/includeme.excluded"])

This matches the same file as in the previous example.

- operator for globs is equivalent to a set difference operation.

new_author

Create a new author from a string with the form 'name foo@bar.com'

author new_author(author_string)

Parameters:

Parameter Description
author_string string

A string representation of the author with the form 'name foo@bar.com'

Example:

Create a new author:
new_author('Foo Bar <foobar@myorg.com>')

parse_message

Returns a ChangeMessage parsed from a well formed string.

ChangeMessage parse_message(message)

Parameters:

Parameter Description
message string

The contents of the change message

hg

Set of functions to define Mercurial (Hg) origins and destinations.

hg.origin

EXPERIMENTAL: Defines a standard Mercurial (Hg) origin.

origin hg.origin(url, ref="default")

Parameters:

Parameter Description
url string

Indicates the URL of the Hg repository
ref string

Represents the default reference that will be used to read a revision from the repository. The reference defaults to default, the most recent revision on the default branch. References can be in a variety of formats:

  • A global identifier for a revision. Example: f4e0e692208520203de05557244e573e981f6c72
  • A bookmark in the repository.
  • A branch in the repository, which returns the tip of that branch. Example: default
  • A tag in the repository. Example: tip

mapping_function

A function that given an object can map to another object

metadata

Core transformations for the change metadata

metadata.add_header

Adds a header line to the commit message. Any variable present in the message in the form of ${LABEL_NAME} will be replaced by the corresponding label in the message. Note that this requires that the label is already in the message or in any of the changes being imported. The label in the message takes priority over the ones in the list of original messages of changes imported.

transformation metadata.add_header(text, ignore_label_not_found=False, new_line=True)

Parameters:

Parameter Description
text string

The header text to include in the message. For example '[Import of foo ${LABEL}]'. This would construct a message resolving ${LABEL} to the corresponding label.
ignore_label_not_found bool

If a label used in the template is not found, ignore the error and don't add the header. By default it will stop the migration and fail.
new_line bool

If a new line should be added between the header and the original message. This allows to create messages like HEADER: ORIGINAL_MESSAGE

Examples:

Add a header always:

Adds a header to any message

metadata.add_header("COPYBARA CHANGE")

Messages like:

A change

Example description for
documentation

Will be transformed into:

COPYBARA CHANGE
A change

Example description for
documentation
Add a header that uses a label:

Adds a header to messages that contain a label. Otherwise it skips the message manipulation.

metadata.add_header("COPYBARA CHANGE FOR https://github.com/myproject/foo/pull/${GITHUB_PR_NUMBER}",
    ignore_label_not_found = True,
)

A change message, imported using git.github_pr_origin, like:

A change

Example description for
documentation

Will be transformed into:

COPYBARA CHANGE FOR https://github.com/myproject/foo/pull/1234
Example description for
documentation

Assuming the PR number is 1234. But any change without that label will not be transformed.

Add a header without new line:

Adds a header without adding a new line before the original message:

metadata.add_header("COPYBARA CHANGE: ", new_line = False)

Messages like:

A change

Example description for
documentation

Will be transformed into:

COPYBARA CHANGE: A change

Example description for
documentation

metadata.expose_label

Certain labels are present in the internal metadata but are not exposed in the message by default. This transformations find a label in the internal metadata and exposes it in the message. If the label is already present in the message it will update it to use the new name and separator.

transformation metadata.expose_label(name, new_name=label, separator="=", ignore_label_not_found=True, all=False, concat_separator=None)

Parameters:

Parameter Description
name string

The label to search
new_name string or NoneType

The name to use in the message
separator string

The separator to use when adding the label to the message
ignore_label_not_found bool

If a label is not found, ignore the error and continue.
all bool

By default Copybara tries to find the most relevant instance of the label. First looking into the message and then looking into the changes in order. If this field is true it exposes all the matches instead.
concat_separator unknown

If all is set, copybara will expose multiple values in one per line. If a separator is specified, it will concat the values instead.

Examples:

Simple usage:

Expose a hidden label called 'REVIEW_URL':

metadata.expose_label('REVIEW_URL')

This would add it as REVIEW_URL=the_value.

New label name:

Expose a hidden label called 'REVIEW_URL' as GIT_REVIEW_URL:

metadata.expose_label('REVIEW_URL', 'GIT_REVIEW_URL')

This would add it as GIT_REVIEW_URL=the_value.

Custom separator:

Expose the label with a custom separator

metadata.expose_label('REVIEW_URL', separator = ': ')

This would add it as REVIEW_URL: the_value.

Expose multiple labels:

Expose all instances of a label in all the changes (SQUASH for example)

metadata.expose_label('REVIEW_URL', all = True)

This would add 0 or more REVIEW_URL: the_value labels to the message.

Expose multiple labels, concatenating the values :

Expose all instances of a label in all the changes (SQUASH for example)

metadata.expose_label('REVIEW_URL', all = True, concat_separator=',')

This would add a REVIEW_URL: value1,value2 label to the message.

metadata.map_author

Map the author name and mail to another author. The mapping can be done by both name and mail or only using any of the two.

transformation metadata.map_author(authors, reversible=False, noop_reverse=False, fail_if_not_found=False, reverse_fail_if_not_found=False, map_all_changes=False)

Parameters:

Parameter Description
authors dict

The author mapping. Keys can be in the form of 'Your Name', 'some@mail' or 'Your Name <some@mail>'. The mapping applies heuristics to know which field to use in the mapping. The value has to be always in the form of 'Your Name <some@mail>'
reversible bool

If the transform is automatically reversible. Workflows using the reverse of this transform will be able to automatically map values to keys.
noop_reverse bool

If true, the reversal of the transformation doesn't do anything. This is useful to avoid having to write core.transformation(metadata.map_author(...), reversal = []).
fail_if_not_found bool

Fail if a mapping cannot be found. Helps discovering early authors that should be in the map
reverse_fail_if_not_found bool

Same as fail_if_not_found but when the transform is used in a inverse workflow.
map_all_changes bool

If all changes being migrated should be mapped. Useful for getting a mapped metadata.squash_notes. By default we only map the current author.

Example:

Map some names, emails and complete authors:

Here we show how to map authors using different options:

metadata.map_author({
    'john' : 'Some Person <some@example.com>',
    'madeupexample@google.com' : 'Other Person <someone@example.com>',
    'John Example <john.example@example.com>' : 'Another Person <some@email.com>',
})

metadata.map_references

Allows updating links to references in commit messages to match the destination's format. Note that this will only consider the 5000 latest commits.

transformation metadata.map_references(before, after, regex_groups={}, additional_import_labels=[])

Parameters:

Parameter Description
before string

Template for origin references in the change message. Use a '${reference}' token to capture the actual references. E.g. if the origin uses links like 'http://changes?1234', the template would be 'http://changes?${reference}', with reference_regex = '[0-9]+'
after string

Format for destination references in the change message. Use a '${reference}' token to represent the destination reference. E.g. if the destination uses links like 'http://changes?1234', the template would be 'http://changes?${reference}', with reference_regex = '[0-9]+'
regex_groups dict

Regexes for the ${reference} token's content. Requires one 'before_ref' entry matching the ${reference} token's content on the before side. Optionally accepts one 'after_ref' used for validation. Copybara uses re2 syntax.
additional_import_labels sequence of string

Meant to be used when migrating from another tool: Per default, copybara will only recognize the labels defined in the workflow's endpoints. The tool will use these additional labels to find labels created by other invocations and tools.

Example:

Map references, origin source of truth:

Finds links to commits in change messages, searches destination to find the equivalent reference in destination. Then replaces matches of 'before' with 'after', replacing the subgroup matched with the destination reference. Assume a message like 'Fixes bug introduced in origin/abcdef', where the origin change 'abcdef' was migrated as '123456' to the destination.

metadata.map_references(
    before = "origin/${reference}",
    after = "destination/${reference}",
    regex_groups = {
        "before_ref": "[0-9a-f]+",
        "after_ref": "[0-9]+",
    },
)

This would be translated into 'Fixes bug introduced in destination/123456', provided that a change with the proper label was found - the message remains unchanged otherwise.

metadata.remove_label

Remove a label from the message

transformation metadata.remove_label(name)

Parameters:

Parameter Description
name string

The label name

Example:

Remove a label:

Remove Change-Id label from the message:

metadata.remove_label('Change-Id')

metadata.replace_message

Replace the change message with a template text. Any variable present in the message in the form of ${LABEL_NAME} will be replaced by the corresponding label in the message. Note that this requires that the label is already in the message or in any of the changes being imported. The label in the message takes priority over the ones in the list of original messages of changes imported.

transformation metadata.replace_message(text, ignore_label_not_found=False)

Parameters:

Parameter Description
text string

The template text to use for the message. For example '[Import of foo ${LABEL}]'. This would construct a message resolving ${LABEL} to the corresponding label.
ignore_label_not_found bool

If a label used in the template is not found, ignore the error and don't add the header. By default it will stop the migration and fail.

Example:

Replace the message:

Replace the original message with a text:

metadata.replace_message("COPYBARA CHANGE: Import of ${GITHUB_PR_NUMBER}\n\n${GITHUB_PR_BODY}\n")

Will transform the message to:

COPYBARA CHANGE: Import of 12345

Body from Github Pull Request

metadata.restore_author

For a given change, restore the author present in the ORIGINAL_AUTHOR label as the author of the change.

transformation metadata.restore_author(label='ORIGINAL_AUTHOR', separator="=", search_all_changes=False)

Parameters:

Parameter Description
label string

The label to use for restoring the author
separator string

The separator to use between the label and the value
search_all_changes bool

By default Copybara only looks in the last current change for the author label. This allows to do the search in all current changes (Only makes sense for SQUASH/CHANGE_REQUEST).

metadata.save_author

For a given change, store a copy of the author as a label with the name ORIGINAL_AUTHOR.

transformation metadata.save_author(label='ORIGINAL_AUTHOR', separator="=")

Parameters:

Parameter Description
label string

The label to use for storing the author
separator string

The separator to use between the label and the value

metadata.scrubber

Removes part of the change message using a regex

transformation metadata.scrubber(regex, msg_if_no_match=None, fail_if_no_match=False, replacement='')

Parameters:

Parameter Description
regex string

Any text matching the regex will be removed. Note that the regex is runs in multiline mode.
msg_if_no_match string or NoneType

If set, Copybara will use this text when the scrubbing regex doesn't match.
fail_if_no_match bool

If set, msg_if_no_match must be None and then fail if the scrubbing regex doesn't match.

replacement string

Text replacement for the matching substrings. References to regex group numbers can be used in the form of $1, $2, etc.

Examples:

Remove from a keyword to the end of the message:

When change messages are in the following format:

Public change description

This is a public description for a commit

CONFIDENTIAL:
This fixes internal project foo-bar

Using the following transformation:

metadata.scrubber('(^|\n)CONFIDENTIAL:(.|\n)*')

Will remove the confidential part, leaving the message as:

Public change description

This is a public description for a commit
Keep only message enclosed in tags:

The previous example is prone to leak confidential information since a developer could easily forget to include the CONFIDENTIAL label. A different approach for this is to scrub everything by default except what is explicitly allowed. For example, the following scrubber would remove anything not enclosed in <public></public> tags:

metadata.scrubber('^(?:\n|.)*<public>((?:\n|.)*)</public>(?:\n|.)*$', replacement = '$1')

So a message like:

this
is
very confidential<public>but this is public
very public
</public>
and this is a secret too

would be transformed into:

but this is public
very public
Use default msg when the scrubbing regex doesn't match:

Assign msg_if_no_match a default msg. For example:

metadata.scrubber('^(?:\n|.)*<public>((?:\n|.)*)</public>(?:\n|.)*$', msg_if_no_match = 'Internal Change.', replacement = '$1')

So a message like:

this
is
very confidential
This is not public msg.

and this is a secret too

would be transformed into:

Internal Change.
Fail if the scrubbing regex doesn't match:

Set fail_if_no_match to true

metadata.scrubber('^(?:\n|.)*<public>((?:\n|.)*)</public>(?:\n|.)*$', fail_if_no_match = True, replacement = '$1')

So a message like:

this
is
very confidential
but this is not public

and this is a secret too

This would fail. Error msg:

Scrubber regex: '^(?:\n|.)*<public>((?:\n|.)*)</public>(?:\n|.)*$' didn't match for description: this
is
very confidential
but this is not public

and this is a secret too

metadata.squash_notes

Generate a message that includes a constant prefix text and a list of changes included in the squash change.

transformation metadata.squash_notes(prefix='Copybara import of the project:\n\n', max=100, compact=True, show_ref=True, show_author=True, show_description=True, oldest_first=False, use_merge=True)

Parameters:

Parameter Description
prefix string

A prefix to be printed before the list of commits.
max int

Max number of commits to include in the message. For the rest a comment like (and x more) will be included. By default 100 commits are included.
compact bool

If compact is set, each change will be shown in just one line
show_ref bool

If each change reference should be present in the notes
show_author bool

If each change author should be present in the notes
show_description bool

If each change description should be present in the notes
oldest_first bool

If set to true, the list shows the oldest changes first. Otherwise it shows the changes in descending order.
use_merge bool

If true then merge changes are included in the squash notes

Examples:

Simple usage:

'Squash notes' default is to print one line per change with information about the author

metadata.squash_notes("Changes for Project Foo:\n")

This transform will generate changes like:

Changes for Project Foo:

  - 1234abcde second commit description by Foo Bar <foo@bar.com>
  - a4321bcde first commit description by Foo Bar <foo@bar.com>
Removing authors and reversing the order:
metadata.squash_notes("Changes for Project Foo:\n",
    oldest_first = True,
    show_author = False,
)

This transform will generate changes like:

Changes for Project Foo:

  - a4321bcde first commit description
  - 1234abcde second commit description
Removing description:
metadata.squash_notes("Changes for Project Foo:\n",
    show_description = False,
)

This transform will generate changes like:

Changes for Project Foo:

  - a4321bcde by Foo Bar <foo@bar.com>
  - 1234abcde by Foo Bar <foo@bar.com>
Showing the full message:
metadata.squash_notes(
  prefix = 'Changes for Project Foo:',
  compact = False
)

This transform will generate changes like:

Changes for Project Foo:
--
2 by Foo Baz <foo@baz.com>:

second commit

Extended text
--
1 by Foo Bar <foo@bar.com>:

first commit

Extended text

metadata.use_last_change

Use metadata (message or/and author) from the last change being migrated. Useful when using 'SQUASH' mode but user only cares about the last change.

transformation metadata.use_last_change(author=True, message=True, default_message=None, use_merge=True)

Parameters:

Parameter Description
author bool

Replace author with the last change author (Could still be the default author if not on the allowlist or using authoring.overwrite.)
message bool

Replace message with last change message.
default_message string or NoneType

Replace message with last change message.
use_merge bool

If true then merge changes are taken into account for looking for the last change.

metadata.verify_match

Verifies that a RegEx matches (or not matches) the change message. Does not transform anything, but will stop the workflow if it fails.

transformation metadata.verify_match(regex, verify_no_match=False)

Parameters:

Parameter Description
regex string

The regex pattern to verify. The re2j pattern will be applied in multiline mode, i.e. '^' refers to the beginning of a file and '$' to its end.
verify_no_match bool

If true, the transformation will verify that the RegEx does not match.

Example:

Check that a text is present in the change description:

Check that the change message contains a text enclosed in <public></public>:

metadata.verify_match("<public>(.|\n)*</public>")

origin_ref

Reference to the change/review in the origin.

Fields:

Name Description
ref string

Origin reference ref

patch

Module for applying patches.

patch.apply

A transformation that applies the given patch files. If a path does not exist in a patch, it will be ignored.

transformation patch.apply(patches=[], excluded_patch_paths=[], series=None, strip=1)

Parameters:

Parameter Description
patches sequence of string

The list of patchfiles to apply, relative to the current config file. The files will be applied relative to the checkout dir and the leading path component will be stripped (-p1).

If series is also specified, these patches will be applied before those ones.

This field doesn't accept a glob.
excluded_patch_paths sequence of string

The list of paths to exclude from each of the patches. Each of the paths will be excluded from all the patches. Note that these are not workdir paths, but paths relative to the patch itself. If not empty, the patch will be applied using 'git apply' instead of GNU Patch.
series string or NoneType

A file which contains a list of patches to apply. The patch files to apply are interpreted relative to this file and must be written one per line. The patches listed in this file will be applied relative to the checkout dir and the leading path component will be stripped (via the -p1 flag).

You can generate a file which matches this format by running 'find . -name *.patch | sort > series'.

If patches is also specified, those patches will be applied before these ones.
strip int

Number of segments to strip. (This sets the -pX flag, for example -p0, -p1, etc.) By default it uses -p1.

Command line flags:

Name Type Description
--patch-bin string Path for GNU Patch command
--patch-skip-version-check boolean Skip checking the version of patch and assume it is fine
--patch-use-git-apply boolean Don't use GNU Patch and instead use 'git apply'
--quilt-bin string Path to quilt command

patch.quilt_apply

A transformation that applies and updates patch files using Quilt. Compared to patch.apply, this transformation supports updating the content of patch files if they can be successfully applied with fuzz. The patch files must be included in the destination_files glob in order to get updated. Underneath, Copybara runs quilt import; quilt push; quilt refresh for each patch file in the series file in order. Currently, all patch files and the series file must reside in a "patches" sub-directory under the root directory containing the migrated code. This means it has the limitation that the migrated code itself cannot contain a directory with the name "patches".

transformation patch.quilt_apply(series)

Parameters:

Parameter Description
series string

A file which contains a list of patches to apply. It is similar to the series parameter in patch.apply transformation, and is required for Quilt. Patches listed in this file will be applied relative to the checkout dir, and the leading path component is stripped via the -p1 flag. Currently this file should be the patches/series file in the root directory of the migrated code.

Example:

Workflow to apply and update patches:

Suppose the destination repository's directory structure looks like:

source_root/BUILD
source_root/copy.bara.sky
source_root/migrated_file1
source_root/migrated_file2
source_root/patches/series
source_root/patches/patch1.patch

Then the transformations in source_root/copy.bara.sky should look like:

[
    patch.quilt_apply(series = "patches/series"),
    core.move("", "source_root"),
]

In this example, patch1.patch is applied to migrated_file1 and/or migrated_file2. patch1.patch itself will be updated during the migration if it is applied with fuzz.

Command line flags:

Name Type Description
--patch-bin string Path for GNU Patch command
--patch-skip-version-check boolean Skip checking the version of patch and assume it is fine
--patch-use-git-apply boolean Don't use GNU Patch and instead use 'git apply'
--quilt-bin string Path to quilt command

Path

Represents a path in the checkout directory

Fields:

Name Description
attr PathAttributes

Get the file attributes, for example size.
name string

Filename of the path. For foo/bar/baz.txt it would be baz.txt
parent unknown

Get the parent path
path string

Full path relative to the checkout directory

path.read_symlink

Read the symlink

Path path.read_symlink()

path.relativize

Constructs a relative path between this path and a given path. For example:
path('a/b').relativize('a/b/c/d')
returns 'c/d'

Path path.relativize(other)

Parameters:

Parameter Description
other Path

The path to relativize against this path

path.resolve

Resolve the given path against this path.

Path path.resolve(child)

Parameters:

Parameter Description
child string or Path

Resolve the given path against this path. The parameter can be a string or a Path.

path.resolve_sibling

Resolve the given path against this path.

Path path.resolve_sibling(other)

Parameters:

Parameter Description
other string or Path

Resolve the given path against this path. The parameter can be a string or a Path.

PathAttributes

Represents a path attributes like size.

Fields:

Name Description
size int

The size of the file. Throws an error if file size > 2GB.
symlink bool

Returns true if it is a symlink

re2

Set of functions to work with regexes in Copybara.

re2.compile

Create a regex pattern

re2_pattern re2.compile(regex)

Parameters:

Parameter Description
regex string

Example:

Simple regex:

Patterns need to be compiled before using them:

re2.compile("a(.*)b").matches('accccb')

re2_matcher

A RE2 regex pattern matcher object to perform regexes in Starlark

re2_matcher.end

Return the end position of a matching group

int re2_matcher.end(group=0)

Parameters:

Parameter Description
group int or string

re2_matcher.find

Return true if the string matches the regex pattern.

bool re2_matcher.find(start=None)

Parameters:

Parameter Description
start int or NoneType

The input position where the search begins

re2_matcher.group

Return a matching group

string re2_matcher.group(group=0)

Parameters:

Parameter Description
group int or string

re2_matcher.group_count

Return the number of groups found for a match

int re2_matcher.group_count()

re2_matcher.matches

Return true if the string matches the regex pattern.

bool re2_matcher.matches()

re2_matcher.replace_all

Replace all instances matching the regex

string re2_matcher.replace_all(replacement=0)

Parameters:

Parameter Description
replacement string

re2_matcher.replace_first

Replace the first instance matching the regex

string re2_matcher.replace_first(replacement=0)

Parameters:

Parameter Description
replacement string

re2_matcher.start

Return the start position of a matching group

int re2_matcher.start(group=0)

Parameters:

Parameter Description
group int or string

re2_pattern

A RE2 regex pattern object to perform regexes in Starlark

re2_pattern.matcher

Return true if the string matches the regex pattern

re2_matcher re2_pattern.matcher(input)

Parameters:

Parameter Description
input string

re2_pattern.matches

Return true if the string matches the regex pattern

bool re2_pattern.matches(input)

Parameters:

Parameter Description
input string

SetReviewInput

Input for posting a review to Gerrit. See https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#review-input

struct

Immutable struct type.

struct

Creates a new immutable struct. Structs with the same keys/values are equal. The struct's keys and values are passed in as keyword arguments.

StructImpl struct()

Example:

Create a struct:

Structs are immutable objects to group values.

my_struct = struct(foo='bar')
x = my_struct.foo

transformation

A single operation which modifies the source checked out from the origin, prior to writing it to the destination. Transformations can also be used to perform validations or checks.

Many common transformations are provided by the built-in libraries, such as core.

Custom transformations can be defined in Starlark code via core.dynamic_transform.

transformation_status

The status of a Transformation that was just run. Either a 'success' or a 'no-op'.

Fields:

Name Description
is_noop bool

Whether this status has the value NO-OP.
is_success bool

Whether this status has the value SUCCESS.

TransformWork

Data about the set of changes that are being migrated. It includes information about changes like: the author to be used for commit, change message, etc. You receive a TransformWork object as an argument when defining a dynamic transform.

Fields:

Name Description
author author

Author to be used in the change
changes Changes

List of changes that will be migrated
console Console

Get an instance of the console to report errors or warnings
message string

Message to be used in the change
params dict

Parameters for the function if created with core.dynamic_transform

ctx.add_label

Add a label to the end of the description

ctx.add_label(label, value, separator="=", hidden=False)

Parameters:

Parameter Description
label string

The label to add
value string

The new value for the label
separator string

The separator to use for the label
hidden bool

Don't show the label in the message but only keep it internally

ctx.add_or_replace_label

Replace an existing label or add it to the end of the description

ctx.add_or_replace_label(label, value, separator="=")

Parameters:

Parameter Description
label string

The label to add/replace
value string

The new value for the label
separator string

The separator to use for the label

ctx.add_text_before_labels

Add a text to the description before the labels paragraph

ctx.add_text_before_labels(text)

Parameters:

Parameter Description
text string

ctx.create_symlink

Create a symlink

ctx.create_symlink(link, target)

Parameters:

Parameter Description
link Path

The link path
target Path

The target path

ctx.destination_api

Returns an api handle for the destination repository. Methods available depend on the destination type. Use with extreme caution, as external calls can make workflow non-deterministic and possibly irreversible. Can have side effects in dry-runmode.

endpoint ctx.destination_api()

ctx.destination_reader

Returns a handle to read files from the destination, if supported by the destination.

destination_reader ctx.destination_reader()

ctx.find_all_labels

Tries to find all the values for a label. First it looks at the generated message (that is, labels that might have been added by previous transformations), then it looks in all the commit messages being imported and finally in the resolved reference passed in the CLI.

sequence of string ctx.find_all_labels(label)

Parameters:

Parameter Description
label string

The label to find

ctx.find_label

Tries to find a label. First it looks at the generated message (that is, labels that might have been added by previous transformations), then it looks in all the commit messages being imported and finally in the resolved reference passed in the CLI. Returns the first such label value found this way.

string ctx.find_label(label)

Parameters:

Parameter Description
label string

The label to find

ctx.new_path

Create a new path

Path ctx.new_path(path)

Parameters:

Parameter Description
path string

The string representing the path, relative to the checkout root directory

ctx.noop

The status returned by a no-op Transformation

transformation_status ctx.noop(message)

Parameters:

Parameter Description
message string

Example:

Define a dynamic transformation:

Create a custom transformation which fails.

def my_transform(ctx):
  # do some stuff
  return ctx.noop('Error! The transform didn\'t do anything.')

ctx.now_as_string

Get current date as a string

string ctx.now_as_string(format="yyyy-MM-dd", zone="UTC")

Parameters:

Parameter Description
format string

The format to use. See: https://docs.oracle.com/javase/8/docs/api/java/time/format/DateTimeFormatter.html for details.
zone string

The timezone id to use. See https://docs.oracle.com/javase/8/docs/api/java/time/ZoneId.html. By default UTC

ctx.origin_api

Returns an api handle for the origin repository. Methods available depend on the origin type. Use with extreme caution, as external calls can make workflow non-deterministic and possibly irreversible. Can have side effects in dry-runmode.

endpoint ctx.origin_api()

ctx.read_path

Read the content of path as UTF-8

string ctx.read_path(path)

Parameters:

Parameter Description
path Path

The Path to read from

ctx.remove_label

Remove a label from the message if present

ctx.remove_label(label, whole_message=False)

Parameters:

Parameter Description
label string

The label to delete
whole_message bool

By default Copybara only looks in the last paragraph for labels. This flagmake it replace labels in the whole message.

ctx.replace_label

Replace a label if it exist in the message

ctx.replace_label(label, value, separator="=", whole_message=False)

Parameters:

Parameter Description
label string

The label to replace
value string

The new value for the label
separator string

The separator to use for the label
whole_message bool

By default Copybara only looks in the last paragraph for labels. This flagmake it replace labels in the whole message.

ctx.run

Run a glob or a transform. For example:
files = ctx.run(glob(['**.java']))
or
ctx.run(core.move("foo", "bar"))
or

unknown ctx.run(runnable)

Parameters:

Parameter Description
runnable glob or transformation

When runnable is a glob, returns a list of files in the workdir which it matches.

When runnable is a transformation, runs it in the workdir.

ctx.set_author

Update the author to be used in the change

ctx.set_author(author)

Parameters:

Parameter Description
author author

ctx.set_executable

Set the executable permission of a file

ctx.set_executable(path, value)

Parameters:

Parameter Description
path Path

The Path to set the executable permission of
value bool

Whether or not the file should be executable

ctx.set_message

Update the message to be used in the change

ctx.set_message(message)

Parameters:

Parameter Description
message string

ctx.success

The status returned by a successful Transformation

transformation_status ctx.success()

Example:

Define a dynamic transformation:

Create a custom transformation which is successful.

def my_transform(ctx):
  # do some stuff
  return ctx.success()

For compatibility reasons, returning nothing is the same as returning success.

ctx.write_path

Write an arbitrary string to a path (UTF-8 will be used)

ctx.write_path(path, content)

Parameters:

Parameter Description
path Path

The Path to write to
content string

The content of the file