jsonrpc2-rs

A JSON-RPC 2.0 client/server library in rust.

How to use

Define the structed value types

You should define the types of the follwing three structed values:

• Request Parameters Reference
• Response Result Reference
• Error Data Reference

For example:

type RequestParams = Vec<u32>;
type ResponseResult = u32;
type ErrorData = String;
   

Define the handler

You should implement the THandler trait to define the server side logic:

#[async_trait]
pub trait THandler<S, R, E>
where
    S: Serialize,
{
    async fn handle(&self, conn: Arc<JsonRpc2<S, R, E>>, request: Request<S>);
} 

For example:

struct Add {}

#[async_trait]
impl THandler<RequestParams, ResponseResult, ErrorData> for Add {
    async fn handle(
        &self,
        json_rpc2: Arc<JsonRpc2<RequestParams, ResponseResult, ErrorData>>,
        request: Request<RequestParams>,
    ) {
        match request.method.as_str() {
            "add" => {
                let params = request.params.unwrap();
                let add_res: u32 = params.iter().sum();
                let response = Response::new(request.id.unwrap(), Some(add_res), None);
                json_rpc2.response(response).unwrap();
            }

            _ => {
                log::info!("unknow method");
            }
        }
    }
}

Init JSON-RPC server

let addr = "127.0.0.1:9002";
let listener = TcpListener::bind(&addr).await.expect("Can't listen");

if let Ok((stream, _)) = listener.accept().await {
    let server_stream = ServerObjectStream::accept(stream)
        .await
        .expect("cannot generate object stream");
    JsonRpc2::new(Box::new(server_stream), Some(Box::new(Add {}))).await;
}

Init JSON-RPC client

let url = url::Url::parse("ws://127.0.0.1:9002/").unwrap();
let client_stream = ClientObjectStream::connect(url)
    .await
    .expect("cannot generate object stream");

let conn_arc =
    JsonRpc2::<_, ResponseResult, ErrorData>::new(Box::new(client_stream), None).await;

Call the function

match conn_arc.call("add", Some(vec![2u32, 3u32, 4u32])).await {
    Ok(response) => {
        let result = response.result.unwrap();
        assert_eq!(result, 9);
    }
    Err(err) => {
        log::error!("call add error: {}", err);
    }
}