API to generate .rs files for ttrpc from protobuf

API to generate .rs files to be used e. g. from build.rs.

Example

build.rs:

```rust use ttrpccodegen::Codegen; use ttrpccodegen::{Customize, ProtobufCustomize};

fn main() { let protos = vec![ "protos/a.proto", "protos/b.proto", ];

Codegen::new()
    .out_dir("protocols/sync")
    .inputs(&protos)
    .include("protocols/protos")
    .rust_protobuf()
    .customize(Customize {
        ..Default::default()
    })
    .rust_protobuf_customize(ProtobufCustomize {
        ..Default::default()
    }
    .run()
    .expect("Gen code failed.");

}

```

Cargo.toml:

[build-dependencies] ttrpc-codegen = "0.2"

Versions

| ttrpc-codegen version | ttrpc version | | ------------- | ------------- | | 0.1.x | <= 0.4.x | | 0.2.x | == 0.5.x | | 0.3.x | == 0.6.x | | 0.4.x | >= 0.7.x |

Alternative

The alternative is to use protoc-rust crate, which relies on protoc command to parse descriptors. Both crates should produce the same result, otherwise please file a bug report.