Regenerate documentation

docs/flatten.md

@@ -23,6 +23,7 @@
 * [rust_proto_library](#rust_proto_library)
 * [rust_proto_repositories](#rust_proto_repositories)
 * [rust_proto_toolchain](#rust_proto_toolchain)
+* [rust_proto_transitive_repositories](#rust_proto_transitive_repositories)
 * [rust_repositories](#rust_repositories)
 * [rust_repository_set](#rust_repository_set)
 * [rust_shared_library](#rust_shared_library)
@@ -1606,6 +1607,20 @@ Declare dependencies needed for proto compilation.
 | <a id="rust_proto_repositories-register_default_toolchain"></a>register_default_toolchain |  If True, the default [rust_proto_toolchain](#rust_proto_toolchain) (<code>@rules_rust//proto:default-proto-toolchain</code>) is registered. This toolchain requires a set of dependencies that were generated using [cargo raze](https://github.com/google/cargo-raze). These will also be loaded.   |  <code>True</code> |
 
 
+<a id="#rust_proto_transitive_repositories"></a>
+
+## rust_proto_transitive_repositories
+
+<pre>
+rust_proto_transitive_repositories()
+</pre>
+
+Load transitive dependencies of the `@rules_rust//proto` rules.
+
+This macro should be called immediately after the `rust_proto_repositories` macro.
+
+
+
 <a id="#rust_repositories"></a>
 
 ## rust_repositories

docs/rust_proto.md

@@ -4,8 +4,119 @@
 * [rust_grpc_library](#rust_grpc_library)
 * [rust_proto_library](#rust_proto_library)
 * [rust_proto_repositories](#rust_proto_repositories)
+* [rust_proto_transitive_repositories](#rust_proto_transitive_repositories)
 * [rust_proto_toolchain](#rust_proto_toolchain)
 
+
+## Overview
+
+These build rules are used for building [protobufs][protobuf]/[gRPC][grpc] in [Rust][rust] with Bazel.
+
+[rust]: http://www.rust-lang.org/
+[protobuf]: https://developers.google.com/protocol-buffers/
+[grpc]: https://grpc.io
+
+See the [protobuf example](../examples/proto) for a more complete example of use.
+
+### Setup
+
+To use the Rust proto rules, add the following to your `WORKSPACE` file to add the
+external repositories for the Rust proto toolchain (in addition to the [rust rules setup](..)):
+
+```python
+load("@rules_rust//proto:repositories.bzl", "rust_proto_repositories")
+
+rust_proto_repositories()
+
+load("@rules_rust//proto:transitive_repositories.bzl", "rust_proto_transitive_repositories")
+
+rust_proto_transitive_repositories()
+```
+
+[raze]: https://github.com/google/cargo-raze
+
+This will load crate dependencies of protobuf that are generated using
+[cargo raze][raze] inside the rules_rust
+repository. However, using those dependencies might conflict with other uses
+of [cargo raze][raze]. If you need to change
+those dependencies, please see the [dedicated section below](#custom-deps).
+
+For additional information about Bazel toolchains, see [here](https://docs.bazel.build/versions/master/toolchains.html).
+
+## <a name="custom-deps">Customizing dependencies
+
+These rules depends on the [`protobuf`](https://crates.io/crates/protobuf) and
+the [`grpc`](https://crates.io/crates/grpc) crates in addition to the [protobuf
+compiler](https://github.com/google/protobuf). To obtain these crates,
+`rust_proto_repositories` imports the given crates using BUILD files generated with
+[`cargo raze`][raze].
+
+If you want to either change the protobuf and gRPC rust compilers, or to
+simply use [`cargo raze`][raze] in a more
+complex scenario (with more dependencies), you must redefine those
+dependencies.
+
+To do this, once you've imported the needed dependencies (see our
+[Cargo.toml](raze/Cargo.toml) file to see the default dependencies), you
+need to create your own toolchain. To do so you can create a BUILD
+file with your toolchain definition, for example:
+
+```python
+load("@rules_rust//proto:toolchain.bzl", "rust_proto_toolchain")
+
+rust_proto_toolchain(
+    name = "proto-toolchain-impl",
+    # Path to the protobuf compiler.
+    protoc = "@com_google_protobuf//:protoc",
+    # Protobuf compiler plugin to generate rust gRPC stubs.
+    grpc_plugin = "//cargo_raze/remote:cargo_bin_protoc_gen_rust_grpc",
+    # Protobuf compiler plugin to generate rust protobuf stubs.
+    proto_plugin = "//cargo_raze/remote:cargo_bin_protoc_gen_rust",
+)
+
+toolchain(
+    name = "proto-toolchain",
+    toolchain = ":proto-toolchain-impl",
+    toolchain_type = "@rules_rust//proto:toolchain",
+)
+```
+
+Now that you have your own toolchain, you need to register it by
+inserting the following statement in your `WORKSPACE` file:
+
+```python
+register_toolchains("//my/toolchains:proto-toolchain")
+```
+
+Finally, you might want to set the `rust_deps` attribute in
+`rust_proto_library` and `rust_grpc_library` to change the compile-time
+dependencies:
+
+```python
+rust_proto_library(
+    ...
+    rust_deps = ["//cargo_raze/remote:protobuf"],
+    ...
+)
+
+rust_grpc_library(
+    ...
+    rust_deps = [
+        "//cargo_raze/remote:protobuf",
+        "//cargo_raze/remote:grpc",
+        "//cargo_raze/remote:tls_api",
+        "//cargo_raze/remote:tls_api_stub",
+    ],
+    ...
+)
+```
+
+__Note__: Ideally, we would inject those dependencies from the toolchain,
+but due to [bazelbuild/bazel#6889](https://github.com/bazelbuild/bazel/issues/6889)
+all dependencies added via the toolchain ends-up being in the wrong
+configuration.
+
+
 <a id="#rust_grpc_library"></a>
 
 ## rust_grpc_library
@@ -167,3 +278,17 @@ Declare dependencies needed for proto compilation.
 | <a id="rust_proto_repositories-register_default_toolchain"></a>register_default_toolchain |  If True, the default [rust_proto_toolchain](#rust_proto_toolchain) (<code>@rules_rust//proto:default-proto-toolchain</code>) is registered. This toolchain requires a set of dependencies that were generated using [cargo raze](https://github.com/google/cargo-raze). These will also be loaded.   |  <code>True</code> |
 
 
+<a id="#rust_proto_transitive_repositories"></a>
+
+## rust_proto_transitive_repositories
+
+<pre>
+rust_proto_transitive_repositories()
+</pre>
+
+Load transitive dependencies of the `@rules_rust//proto` rules.
+
+This macro should be called immediately after the `rust_proto_repositories` macro.
+
+
+