hatch-protobuf 0.2.0.post1

A Hatch build plugin to generate Python files from Protocol Buffers .proto files

Hatch Protocol Buffers Generator

This Hatch plugin uses grpcio to generate Python files from Protocol Buffers .proto files.

Usage

You will need to add hatch-protobuf to your project's pyproject.toml:

[tool.hatch.build.hooks.protobuf]
dependencies = ["hatch-protobuf"]

There are a few options that can be set in the [tool.hatch.build.hooks.protobuf] section:

Key	Default	Description
generate_grpc	true	Whether to generate gRPC output files.
generate_pyi	true	Whether to generate .pyi output files. Note that these are not generated for the gRPC output. You may want to use mypy-protobuf instead.
proto_paths	["."] or ["src"]	An array of paths to search for .proto files. Also passed as --proto_path arguments to protoc.
output_path	"." or "src"	The default output directory. This can be overridden on a per-generator basis for custom generators.

Hatch-protobuf will guess whether to use "src" as the default input/output directory in a similar way to the wheel builder. If src/<NAME>/__init__.py exists, but <NAME>/__init__.py does not, it will use "src" as the default for proto_paths and output_path. Otherwise it will use "." as the default for both.

Custom generators

If you want to use custom generators (not just the python, gRPC and pyi ones built in to the version of protoc that ships with grpcio-tools), you can add them in [[tool.hatch.build.hooks.protobuf.generators]] sections. You will also need to add the plugin to the list of dependencies. See the "Mypy output" section below for an example. Options that can be set in generator sections:

Key	Default	Description
name	required	The name of the plugin. The argument passed to protoc will be --<name>_out.
outputs	required	A list of paths (relative to output_path). See below for more information.
output_path	same as output_path from the main protobuf config section	Where to write generated files to. This is the value passed to the --<name>_out argument.

Each entry in the outputs field is a template that depends on the .proto file being processed. The string {proto_name} will be replaced with the base filename of each input .proto file, and {proto_path} will be replaced with the path (relative to the proto_paths) of the input proto files. For example, if proto_paths is set to ["src"], for the input file src/foo/bar/test.proto "{proto_name}" will expand to "test" and "{proto_path}" will expand to "foo/bar".

Mypy output

The mypy-protobuf package provides mypy stub files with comments copied from the input .proto files. Here is an example of how to use it in your pyproject.toml:

[tool.hatch.build.hooks.protobuf]
dependencies = [
    "hatch-protobuf",
    "mypy-protobuf~=3.0",
]
generate_pyi = false  # we'll let mypy-protobuf do this

[[tool.hatch.build.hooks.protobuf.generators]]
name = "mypy"
outputs = ["{proto_path}/{proto_name}_pb2.pyi"]

[[tool.hatch.build.hooks.protobuf.generators]]
name = "mypy_grpc"
outputs = ["{proto_path}/{proto_name}_pb2_grpc.pyi"]