An implementation of the protobuf compiler in rust, intended for use as a library with crates such as prost-build to avoid needing to build protoc.

Compiling a single source file:

assert_eq!(protox::compile(["root.proto"], ["."]).unwrap(), FileDescriptorSet {
    file: vec![
        FileDescriptorProto {
            name: Some("root.proto".to_owned()),
            /* ... */
        }
    ],
});

Usage with prost-build:

let file_descriptors = protox::compile(["root.proto"], ["."]).unwrap();
prost_build::compile_fds(file_descriptors).unwrap();

Usage with tonic-build:

let file_descriptors = protox::compile(["root.proto"], ["."]).unwrap();

tonic_build::configure()
    .build_server(true)
    .compile_fds(file_descriptors)
    .unwrap();

This crate uses miette to add additional details to errors. For nice error messages, add miette as a dependency with the fancy feature enabled and return a miette::Result from your build script.

fn main() -> miette::Result<()> {
  let _ = protox::compile(["root.proto"], ["."])?;

  Ok(())
}

Example error message:

Error:
  × name 'Bar' is not defined
   ╭─[root.proto:3:1]
 3 │ message Foo {
 4 │     Bar bar = 1;
   ·     ─┬─
   ·      ╰── found here
 5 │ }
   ╰────

Rust 1.74 or higher.

The minimum supported Rust version may be changed in the future, but it will be done with a minor version bump.

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

• prost - a protocol buffers implementation for the Rust Language
• protoxy - python bindings for protox