`protobuf_generate`

protobuf_generate runs one built-in protoc generator with a managed compiler. It registers generation as a root task and returns its dependency.

Arguments

Argument	Required	Description
`sources`	Yes	Non-empty list of project-relative `.proto` files.
`generator`	Yes	Built-in generator name or a generator returned by `protobuf_generator` or a language package helper.
`output`	Yes	Project-relative output directory.
`proto_paths`	No	Non-empty list of project-relative import roots. Defaults to `["."]`.
`options`	No	Generator option strings, each passed through the matching `--<generator>_opt` flag. Defaults to `[]`.
`deps`	No	Dependencies activated before generation, in list order. Defaults to `[]`.

The selected compiler is implicit; do not add protoc to deps. xx appends the managed package's bundled include directory after proto_paths, so imports such as google/protobuf/timestamp.proto resolve without extra configuration. Source files, import roots, and outputs must remain inside the project after symlinks are resolved. Missing output directories are created. Output trees cannot contain symbolic links or overlap another active output.

String generators are limited to cpp, csharp, java, js, kotlin, objc, php, pyi, python, rbs, ruby, and rust. These built-ins vary by Protobuf version. For example, js exists only in older releases, while newer generators require newer releases. Unsupported generator/version combinations fail in protoc.

Plugin dependencies must be wrapped in a typed generator. Selecting one activates its installation dependency automatically before protoc; do not also add it to deps. Prefer language-specific helpers such as go_protobuf. protobuf_generate contains no language-specific installation behavior.

Example

load("@[email protected]", "protobuf_generate")

protobuf_generate(
    sources=["proto/example/v1/service.proto"],
    generator="python",
    output="generated/python",
    proto_paths=["proto"],
)

Go plugin example

load("@[email protected]", "go_protobuf")
load("@[email protected]", "protobuf_generate")

protobuf_generate(
    sources=["proto/example/v1/service.proto"],
    generator=go_protobuf("1.36.6"),
    output="generated/go",
    proto_paths=["proto"],
    options=["paths=source_relative"],
)