ttrpc-rust

ttrpc-rust is a non-core subproject of containerd

ttrpc-rust is the Rust version of ttrpc. ttrpc is GRPC for low-memory environments.

The ttrpc compiler of ttrpc-rust ttrpc_rust_plugin is modified from gRPC compiler of gRPC-rs grpcio-compiler.

Usage

1. Generate with protoc command

To generate the sources from proto files:

1. Install protoc from github.com/protocolbuffers/protobuf

2. Install protobuf-codegen

   cargo install --force protobuf-codegen

3. Install ttrpc_rust_plugin from ttrpc-rust/compiler

   cd ttrpc-rust/compiler
   cargo install --force --path .

4. Generate the sources:

$ protoc --rust_out=. --ttrpc_out=. --plugin=protoc-gen-ttrpc=`which ttrpc_rust_plugin` example.proto

2. Generate programmatically

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

Example code:

fn main() {
    protoc_rust_ttrpc::Codegen::new()
        .out_dir("protocols")
        .inputs(&[
            "protocols/protos/agent.proto",
        ])
        .include("protocols/protos")
        .rust_protobuf() // also generate protobuf messages, not just services
        .run()
        .expect("Codegen failed.");
}

async/.await

ttrpc-rust supports async/.await. By using async/.await you can reduce the overhead and resource consumption caused by threads.

Usage

1. Generate codes in async version

Currently we only support generating async codes by using ttrpc-codegen

    ttrpc_codegen::Codegen::new()
        .out_dir("protocols/asynchronous")
        .inputs(&protos)
        .include("protocols/protos")
        .rust_protobuf()
        .customize(Customize {
            gen_mod: true, // Gen mod will add mod.rs in out_dir.It's compatible with protobuf's gen_mod_rs
            async_all: true, // It's the key option.
            ..Default::default()
        })
        .run()
        .expect("Gen async codes failed.");

Provide customize option

• async_all: generate async codes for both server and client
• async_server: generate async codes for server
• async_client: generate async codes for client
• gen_mod: generate mod.rs in out_dir

See more in example/build.rs

2. Write your implemention in async/.await's way

Please follow the guidlines in example/async-server.rs and example/async-client.rs

Run Examples

1. Go to the directory

   $ cd ttrpc-rust/example

2. Start the server

   $ cargo run --example server

   or

   $ cargo run --example async-server

3. Start a client

   $ cargo run --example client

   or

   $ cargo run --example async-client

Notes: the version of protobuf

protobuf-codegen, ttrpc_rust_plugin and your code should use the same version protobuf. You will get following fail if use the different version protobuf.

27 | const _PROTOBUF_VERSION_CHECK: () = ::protobuf::VERSION_2_8_0;
   |                                                 ^^^^^^^^^^^^^ help: a constant with a similar name exists: `VERSION_2_10_1`

The reason is that files generated by protobuf-codegen are compatible only with the same version of runtime

To fix this issue:

1. Rebuild protobuf-codegen with new protobuf:

   cd grpc-rs
   cargo clean
   cargo update
   cargo install --force protobuf-codegen

2. Rebuild ttrpc_rust_plugin with new protobuf:

   cd ttrpc-rust/compiler
   cargo clean
   cargo update
   cargo install --force --path .

3. Build your project.