pub mod generated {
include!(concat!(env!("OUT_DIR"), "/generated.rs"));
}Some projects require additional steps to run before they can be built, e.g. for code generation. Cargo supports this by means of a build.rs file.
build.rs is itself written in Rust. It resides in the root directory of your package, not in src/.
it can have its own list of dependencies via [build-dependencies]
input is communicated via environment variables
output files should be written to OUT_DIR
Cargo behavior can be controlled by writing commands to stdout.
Generated code is typically then included in another Rust source file:
pub mod generated {
include!(concat!(env!("OUT_DIR"), "/generated.rs"));
}Several crates exist - we’re going to use prost here.
By using prost::Message you get encode & decode functionality.
use prost::Message;
// ...
let mut buf = Vec::new(3);
a_proto_object.encode(&mut buf)?;
let another_proto_object = TheProtoObject::decode(a_vec.as_slice())?;