extern crate rs_jsonrpc_core; use std::time::Instant; use std::sync::atomic::{self, AtomicUsize}; use rs_jsonrpc_core::*; use rs_jsonrpc_core::futures::Future; #[derive(Clone, Default, Debug)] struct Meta(usize); impl Metadata for Meta {} #[derive(Default)] struct MyMiddleware(AtomicUsize); impl Middleware for MyMiddleware { type Future = FutureResponse; fn on_request(&self, request: Request, meta: Meta, next: F) -> FutureResponse where F: FnOnce(Request, Meta) -> X + Send, X: Future, Error=()> + Send + 'static, { let start = Instant::now(); let request_number = self.0.fetch_add(1, atomic::Ordering::SeqCst); println!("Processing request {}: {:?}, {:?}", request_number, request, meta); Box::new(next(request, meta).map(move |res| { println!("Processing took: {:?}", start.elapsed()); res })) } } pub fn main() { let mut io = MetaIoHandler::with_middleware(MyMiddleware::default()); io.add_method_with_meta("say_hello", |_params: Params, meta: Meta| { Ok(Value::String(format!("Hello World: {}", meta.0))) }); let request = r#"{"jsonrpc": "2.0", "method": "say_hello", "params": [42, 23], "id": 1}"#; let response = r#"{"jsonrpc":"2.0","result":"Hello World: 5","id":1}"#; let headers = 5; assert_eq!( io.handle_request(request, Meta(headers)).wait().unwrap(), Some(response.to_owned()) ); }