Easy JSON RPC

根据特质定义生成 rpc 处理器和客户端辅助工具。 文档

定义 API

use easy_jsonrpc;

#[easy_jsonrpc::rpc]
pub trait Adder {
    fn checked_add(&self, a: isize, b: isize) -> Option<isize>;
    fn wrapping_add(&self, a: isize, b: isize) -> isize;
    fn is_some(&self, a: Option<usize>) -> bool {
        a.is_some()
    }
    fn takes_ref(&self, rf: &isize);
}

rpc 宏生成

1. &dyn Adder 的 Handler 特质实现
2. rpc 客户端的辅助模块

服务器端使用

use easy_jsonrpc::{Handler, MaybeReply};
use serde_json::json;

struct AdderImpl;

impl Adder for AdderImpl {
    fn checked_add(&self, a: isize, b: isize) -> Option<isize> { a.checked_add(b) }
    fn wrapping_add(&self, a: isize, b: isize) -> isize { a.wrapping_add(b) }
    fn takes_ref(&self, rf: &isize) {}
}

let handler = (&AdderImpl {} as &dyn Adder);

assert_eq!(
    handler.handle_request(json!({
        "jsonrpc": "2.0",
        "method": "wrapping_add",
        "params": [1, 2],
        "id": 1
    })),
    MaybeReply::Reply(json!({
        "jsonrpc": "2.0",
        "result": 3,
        "id": 1
    }))
);

客户端使用

let bind = adder::checked_add(1, 2).unwrap();
let (call, tracker) = bind.call();
let json_response = match handler.handle_request(call.as_request()) {
   MaybeReply::Reply(resp) => resp,
   MaybeReply::DontReply => panic!(),
};
let mut response = easy_jsonrpc::Response::from_json_response(json_response).unwrap();
assert_eq!(tracker.get_return(&mut response).unwrap(), Some(3));

额外功能

命名参数可以免费处理。

assert_eq!(
    handler.handle_request(json!({
        "jsonrpc": "2.0",
        "method": "wrapping_add",
        "params": {
            "a": 1,
            "b": 2
        },
        "id": 1
    })),
    MaybeReply::Reply(json!({
        "jsonrpc": "2.0",
        "result": 3,
        "id": 1
    }))
);

通知（不带 id 的调用）被合理处理。

assert_eq!(
    handler.handle_request(json!({
        "jsonrpc": "2.0",
        "method": "wrapping_add",
        "params": [1, 1]
    })),
    MaybeReply::DontReply
);

生成通知很容易。

let bind = adder::checked_add(0, 0).unwrap();
let notification = bind.notification().as_request();
assert_eq!(handler.handle_request(notification), MaybeReply::DontReply);

支持批量调用。

use easy_jsonrpc::Call;
let bind0 = adder::checked_add(0, 0).unwrap();
let (call0, tracker0) = bind0.call();
let bind1 = adder::checked_add(1, 0).unwrap();
let (call1, tracker1) = bind1.call();
let bind2 = adder::wrapping_add(1, 1).unwrap();
let (call2, tracker2) = bind2.call();
let bind3 = adder::wrapping_add(1, 1).unwrap();
let call3 = bind3.notification();
let json_request = Call::batch_request(&[call0, call1, call2, call3]);
let json_response = match handler.handle_request(json_request) {
   MaybeReply::Reply(resp) => resp,
   MaybeReply::DontReply => panic!(),
};
let mut response = easy_jsonrpc::Response::from_json_response(json_response).unwrap();
assert_eq!(tracker1.get_return(&mut response).unwrap(), Some(1));
assert_eq!(tracker0.get_return(&mut response).unwrap(), Some(0));
assert_eq!(tracker2.get_return(&mut response).unwrap(), 2);