From 524a453b6fe1bc5bd5086a15b727cbd4168e5736 Mon Sep 17 00:00:00 2001 From: messense Date: Fri, 12 Jul 2019 14:21:34 +0800 Subject: [PATCH] docs(examples): Update web_api example to use async await --- examples_disabled/web_api.rs | 123 +++++++++++++++++------------------ 1 file changed, 61 insertions(+), 62 deletions(-) diff --git a/examples_disabled/web_api.rs b/examples_disabled/web_api.rs index 32f02ee2..fa5fcd9e 100644 --- a/examples_disabled/web_api.rs +++ b/examples_disabled/web_api.rs @@ -1,24 +1,24 @@ +#![feature(async_await)] #![deny(warnings)] -extern crate futures; extern crate hyper; extern crate pretty_env_logger; extern crate serde_json; -use futures::{future, Future, Stream}; - use hyper::{Body, Chunk, Client, Method, Request, Response, Server, StatusCode, header}; use hyper::client::HttpConnector; -use hyper::service::service_fn; +use hyper::service::{service_fn, make_service_fn}; +use futures_util::{TryStreamExt}; + +type GenericError = Box; static NOTFOUND: &[u8] = b"Not Found"; static URL: &str = "http://127.0.0.1:1337/json_api"; static INDEX: &[u8] = b"test.html"; static POST_DATA: &str = r#"{"original": "data"}"#; -type GenericError = Box; -type ResponseFuture = Box, Error=GenericError> + Send>; - -fn client_request_response(client: &Client) -> ResponseFuture { +async fn client_request_response(client: &Client) + -> Result, GenericError> +{ let req = Request::builder() .method(Method::POST) .uri(URL) @@ -26,39 +26,35 @@ fn client_request_response(client: &Client) -> ResponseFuture { .body(POST_DATA.into()) .unwrap(); - Box::new(client.request(req).from_err().map(|web_res| { - // Compare the JSON we sent (before) with what we received (after): - let body = Body::wrap_stream(web_res.into_body().map(|b| { - Chunk::from(format!("POST request body: {}
Response: {}", - POST_DATA, - std::str::from_utf8(&b).unwrap())) - })); + let web_res = client.request(req).await?; + // Compare the JSON we sent (before) with what we received (after): + let body = Body::wrap_stream(web_res.into_body().map_ok(|b| { + Chunk::from(format!("POST request body: {}
Response: {}", + POST_DATA, + std::str::from_utf8(&b).unwrap())) + })); - Response::new(body) - })) + Ok(Response::new(body)) } -fn api_post_response(req: Request) -> ResponseFuture { +async fn api_post_response(req: Request) + -> Result, GenericError> +{ // A web api to run against - Box::new(req.into_body() - .concat2() // Concatenate all chunks in the body - .from_err() - .and_then(|entire_body| { - // TODO: Replace all unwraps with proper error handling - let str = String::from_utf8(entire_body.to_vec())?; - let mut data : serde_json::Value = serde_json::from_str(&str)?; - data["test"] = serde_json::Value::from("test_value"); - let json = serde_json::to_string(&data)?; - let response = Response::builder() - .status(StatusCode::OK) - .header(header::CONTENT_TYPE, "application/json") - .body(Body::from(json))?; - Ok(response) - }) - ) + let entire_body = req.into_body().try_concat().await?; + // TODO: Replace all unwraps with proper error handling + let str = String::from_utf8(entire_body.to_vec())?; + let mut data : serde_json::Value = serde_json::from_str(&str)?; + data["test"] = serde_json::Value::from("test_value"); + let json = serde_json::to_string(&data)?; + let response = Response::builder() + .status(StatusCode::OK) + .header(header::CONTENT_TYPE, "application/json") + .body(Body::from(json))?; + Ok(response) } -fn api_get_response() -> ResponseFuture { +async fn api_get_response() -> Result, GenericError> { let data = vec!["foo", "bar"]; let res = match serde_json::to_string(&data) { Ok(json) => { @@ -74,59 +70,62 @@ fn api_get_response() -> ResponseFuture { .unwrap() } }; - - Box::new(future::ok(res)) + Ok(res) } -fn response_examples(req: Request, client: &Client) -> ResponseFuture { +async fn response_examples(req: Request, client: &Client) + -> Result, GenericError> +{ match (req.method(), req.uri().path()) { (&Method::GET, "/") | (&Method::GET, "/index.html") => { let body = Body::from(INDEX); - Box::new(future::ok(Response::new(body))) + Ok(Response::new(body)) }, (&Method::GET, "/test.html") => { - client_request_response(client) + client_request_response(client).await }, (&Method::POST, "/json_api") => { - api_post_response(req) + api_post_response(req).await }, (&Method::GET, "/json_api") => { - api_get_response() + api_get_response().await } _ => { // Return 404 not found response. let body = Body::from(NOTFOUND); - Box::new(future::ok(Response::builder() - .status(StatusCode::NOT_FOUND) - .body(body) - .unwrap())) + Ok(Response::builder() + .status(StatusCode::NOT_FOUND) + .body(body) + .unwrap()) } } } -fn main() { +#[hyper::rt::main] +async fn main() -> Result<(), GenericError> { pretty_env_logger::init(); let addr = "127.0.0.1:1337".parse().unwrap(); - hyper::rt::run(future::lazy(move || { - // Share a `Client` with all `Service`s - let client = Client::new(); + // Share a `Client` with all `Service`s + let client = Client::new(); - let new_service = move || { - // Move a clone of `client` into the `service_fn`. - let client = client.clone(); - service_fn(move |req| { + let new_service = make_service_fn(move |_| { + // Move a clone of `client` into the `service_fn`. + let client = client.clone(); + async { + Ok::<_, GenericError>(service_fn(move |req| { response_examples(req, &client) - }) - }; + })) + } + }); - let server = Server::bind(&addr) - .serve(new_service) - .map_err(|e| eprintln!("server error: {}", e)); + let server = Server::bind(&addr) + .serve(new_service); - println!("Listening on http://{}", addr); + println!("Listening on http://{}", addr); - server - })); + server.await?; + + Ok(()) }