simple proxy example #1096

vandenoever · 2017-03-19T15:26:58Z

Hyper has client and server http support and can probably be used to write an HTTP proxy. @fmonjalet claims to have already written one. In Node.JS it's very simple to write such a proxy in a few lines.

Here is my attempt at doing this with Hyper. The return type from fn call is wrong and I've no idea how to fix it. Such a simple proxy would be an useful addition to examples/.

//#![deny(warnings)]
extern crate futures;
extern crate hyper;
extern crate tokio_core;

use futures::Future;
use futures::future::FutureResult;
use hyper::{client, server, Client, Url};

#[derive(Clone, Copy)]
struct Proxy;

fn server_request_to_client_request(req: &server::Request) -> client::Request {
    // todo: handle parse error
    let url = Url::parse(&format!("{}", req.uri())).unwrap();
    let mut client_req = client::Request::new(req.method().clone(), url);
    client_req.set_version(req.version().clone());
    *client_req.headers_mut() = *req.headers();
    client_req
}

impl server::Service for Proxy {
    type Request = server::Request;
    type Response = server::Response;
    type Error = hyper::Error;
    type Future = FutureResult<server::Response, hyper::Error>;

    fn call(&self, req: server::Request) -> Self::Future {
        let mut core = tokio_core::reactor::Core::new().unwrap();
        let handle = core.handle();
        let client = Client::new(&handle);
        let mut client_req = server_request_to_client_request(&req);
        client_req.set_body(req.body());

        client.request(client_req)
            .and_then(|res| {
                let mut resp: server::Response = server::Response::new();
                resp = resp.with_headers(res.headers().clone());
                resp.set_status(res.status().clone());
                resp.set_body(res.body());
                futures::future::ok(resp)
            })
    }
}

fn main() {
    let addr = "127.0.0.1:1337".parse().unwrap();

    let server = server::Http::new().bind(&addr, || Ok(Proxy)).unwrap();
    println!("Listening on http://{} with 1 thread.",
             server.local_addr().unwrap());
    server.run().unwrap();
}

The proxy can be tested with

http_proxy=http://localhost:1337 wget http://w3.org

vandenoever · 2017-03-19T19:54:45Z

This version compiles with master but does not return any data.
The closure in and_then() is never called.
The error that is printed is

oops, an error Io(Error { repr: Custom(Custom { kind: Other, error: StringError("event loop gone") }) })

extern crate futures;
extern crate hyper;
extern crate tokio_core;

use futures::Future;
use hyper::{client, server, Client, Url};

struct Proxy;

fn server_request_to_client_request(req: &server::Request) -> client::Request {
    // todo: handle parse error
    let url = Url::parse(&format!("{}", req.uri())).unwrap();
    let mut client_req = client::Request::new(req.method().clone(), url);
    client_req.set_version(req.version().clone());
    *client_req.headers_mut() = req.headers().clone();
    client_req
}

impl server::Service for Proxy {
    type Request = server::Request;
    type Response = server::Response;
    type Error = hyper::Error;
    type Future = Box<Future<Item = Self::Response, Error = ::hyper::Error>>;

    fn call(&self, req: server::Request) -> Self::Future {
        let core = tokio_core::reactor::Core::new().unwrap();
        let handle = core.handle().clone();
        let client = Client::new(&handle);
        let mut client_req = server_request_to_client_request(&req);
        println!("got request {}", req.uri());
        client_req.set_body(req.body());

        Box::new(client.request(client_req)
            .map_err(|e| {
                println!("oops, an error {:?}", e);
                e
            })
            .and_then(|res| {
                println!("got response {}", res.headers());
                let mut resp: server::Response = server::Response::new();
                resp = resp.with_headers(res.headers().clone());
                resp.set_status(res.status().clone());
                resp.set_body(res.body());
                futures::future::ok(resp)
            }))
    }
}

fn main() {
    let addr = "127.0.0.1:1337".parse().unwrap();
    let server = server::Http::new().bind(&addr, || Ok(Proxy {})).unwrap();
    println!("Listening on http://{} with 1 thread.",
             server.local_addr().unwrap());
    server.run().unwrap();
}

vandenoever · 2017-03-19T21:19:20Z

Here is a version that uses a tokio Core per Service. This does not print error but hangs. The reason is probably that it mixes multiple event loops. The code hangs on one loop while another has data.

//#![deny(warnings)]
extern crate futures;
extern crate hyper;
extern crate tokio_core;

use futures::Future;
use hyper::{client, server, Client, Url};

struct Proxy {
    core: tokio_core::reactor::Core,
}

fn server_request_to_client_request(req: &server::Request) -> client::Request {
    // todo: handle parse error
    let url = Url::parse(&format!("{}", req.uri())).unwrap();
    let mut client_req = client::Request::new(req.method().clone(), url);
    client_req.set_version(req.version().clone());
    *client_req.headers_mut() = req.headers().clone();
    client_req
}

impl server::Service for Proxy {
    type Request = server::Request;
    type Response = server::Response;
    type Error = hyper::Error;
    type Future = Box<Future<Item = Self::Response, Error = ::hyper::Error>>;

    fn call(&self, req: server::Request) -> Self::Future {
        let client = Client::new(&self.core.handle());
        let mut client_req = server_request_to_client_request(&req);
        println!("got request {}", req.uri());
        client_req.set_body(req.body());

        Box::new(client.request(client_req)
            .map_err(|e| {
                println!("oops, an error {:?}", e);
                e
            })
            .and_then(|res| {
                println!("got response {}", res.headers());
                let mut resp: server::Response = server::Response::new();
                resp = resp.with_headers(res.headers().clone());
                resp.set_status(res.status().clone());
                resp.set_body(res.body());
                futures::future::ok(resp)
            }))
    }
}

fn main() {
    let addr = "127.0.0.1:1337".parse().unwrap();
    let server = server::Http::new()
        .bind(&addr, || {
            let core = tokio_core::reactor::Core::new().unwrap();
            Ok(Proxy { core: core })
        })
        .unwrap();

    println!("Listening on http://{} with 1 thread.",
             server.local_addr().unwrap());
    server.run().unwrap();
}

chrmod · 2017-04-24T17:52:18Z

I would be very much interested in such example code. Found another, apparently also not working approach https://gist.github.com/infinityb/600c22ae549cecf43244 (maybe I'm using wrong version of the libraries)

meganehouser · 2017-04-26T03:59:17Z

I wrote a simple proxy server with single event loop.
https://gist.github.com/meganehouser/d5e1b47eb2873797ebdc440b0ed482df
I referred to weldr.

Hoverbear · 2017-05-17T10:16:12Z

Please feel free to submit a PR with such example code! If you need help doing this let me know.

jbg · 2017-12-01T11:04:03Z

https://github.com/jbg/prox/blob/master/src/main.rs

terry90 · 2018-05-23T13:32:29Z

I'm currently writing a simple proxy with possibility of custom middlewares.
Since I'm a new rustacean, do not expect the code to be the most opti.
https://github.com/terry90/rs-simple-proxy

meganehouser mentioned this issue May 17, 2017

feat(example): add an example http proxy server #1179

Closed

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hyperium / hyper

simple proxy example #1096

simple proxy example #1096

vandenoever commented Mar 19, 2017 •

edited

vandenoever commented Mar 19, 2017 •

edited

vandenoever commented Mar 19, 2017

chrmod commented Apr 24, 2017

meganehouser commented Apr 26, 2017

Hoverbear commented May 17, 2017

jbg commented Dec 1, 2017

terry90 commented May 23, 2018

hyperium / hyper

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simple proxy example #1096

simple proxy example #1096

Comments

vandenoever commented Mar 19, 2017 • edited

vandenoever commented Mar 19, 2017 • edited

vandenoever commented Mar 19, 2017

chrmod commented Apr 24, 2017

meganehouser commented Apr 26, 2017

Hoverbear commented May 17, 2017

jbg commented Dec 1, 2017

terry90 commented May 23, 2018

vandenoever commented Mar 19, 2017 •

edited

vandenoever commented Mar 19, 2017 •

edited