gomigrate

A SQL database migration toolkit in Golang that supports migrations from multiple sources including in memory and files on disk.

Supported databases

• PostgreSQL
• CockroachDB
• MariaDB
• MySQL
• Sqlite3
• MSSQL

Usage

First import the package:

import "github.com/derkan/gomigrate"

Load Migrations from disk:

m, err = gomigrate.MigrationsFromPath(path, logger)
if err != nil {
  // deal with error
}

Given a database/sql database connection to a PostgreSQL database, db, and a directory to migration files, create a migrator:

migrator, _ := gomigrate.NewMigratorWithMigrations(db, gomigrate.Postgres{}, m)
migrator.Logger = logger

You may also specify a specific logger to use at creation time supporting interface:

type Logger interface {
	Print(v ...interface{})
	Printf(format string, v ...interface{})
	Println(v ...interface{})
	Fatalf(format string, v ...interface{})
}

;such as logrus:

migrator, _ := gomigrate.NewMigratorWithLogger(db, gomigrate.Postgres{}, m, logrus.New())

To migrate the database, run:

err := migrator.Migrate()

To rollback the last migration, run:

err := migrator.Rollback()

Migration files

Migration files need to follow a standard format and must be present in the same directory. Given "up" and "down" steps for a migration, create a file for each by following this template:

{{ id }}_{{ name }}_{{ "up" or "down" }}.sql

For a given migration, the id and name fields must be the same. The id field is an integer that corresponds to the order in which the migration should run relative to the other migrations.

id should not be 0 as that value is used for internal validations.

Custom delimiter

By default SQL clauses are delimited with ";", you can set a new delimiter by adding following as first line to migration sql file(for example set delimiter to #): delimiter #

Example

If I'm trying to add a "users" table to the database, I would create the following two files:

1_add_users_table_up.sql

CREATE TABLE users();

1_add_users_table_down.sql

DROP TABLE users;

Migrations from Memory

Migrations can also be embedded directly in your go code and passed into the Migrator. This can be useful for testdata fixtures or using go-bindata to build fixture data into your go binary.

	migrations := []*Migration{
		{
			ID:   100,
			Name: "FirstMigration",
			Up: `CREATE TABLE first_table (
				id INTEGER PRIMARY KEY
			)`,
			Down: `drop table "first_table"`,
		},
		{
			ID:   110,
			Name: "SecondMigration",
			Up: `CREATE TABLE second_table (
				id INTEGER PRIMARY KEY
			)`,
			Down: `drop table "second_table"`,
		},
	}
	migrator, _ := gomigrate.NewMigratorWithMigrations(db, gomigrate.Postgres{}, migrations)
	migrator.Migrate()

Copyright

Copyright (c) 2014 David Huie. See LICENSE.txt for further details.