#http #proxy #networking

fastforward

a library for implementing custom reverse proxies

8 releases (4 breaking)

0.5.1 Nov 30, 2020
0.5.0 Nov 30, 2020
0.4.1 May 31, 2020
0.4.0 Apr 5, 2020
0.1.0 Mar 22, 2020

#700 in Network programming

50 downloads per month

MIT license

17KB
304 lines

Build Status [minimum rustc 1.31

fastforward

Fastforward is library for writing reverse proxies in rust.

usage - simple_proxy

To implement a proxy that just receives traffic on listen_addr and forwards the it to proxy_addr use the simple_proxy function.

extern crate fastforward;
extern crate http;

use std::net::SocketAddr;
use proxy::simple_proxy;

fn main() {
    let listen_addr: SocketAddr = "127.0.0.1:8080".parse().unwrap();
    let proxy_addr: SocketAddr = "127.0.0.1:4000".parse().unwrap();

    println!("running on port :8080");
    simple_proxy(listen_addr, proxy_addr);
}

usage - generic_proxy

To implement arbitrary logic for your proxy write a request director function. The request, after be passed into the director, will be proxied to the address specified by the "Host" header on the request.

extern crate fastforward;
extern crate http;

use http::{
    header::HeaderValue,
    Response
};
use std::io;
use std::net::SocketAddr;
use fastforward::generic_proxy;


// The director function mutates the incoming request before proxying it.
// In this example, the request URI is changed to the proxy URI.
// This examle mimics the functionality of the `simple_proxy` function.
fn req_transform(req: &mut http::Request<Vec<u8>>) -> Option<Response<Vec<u8>>> { 
   // set the variables
   let proxy_addr = HeaderValue::from_str("127.0.0.1:4000").unwrap();

   let req_headers = req.headers_mut();
   req_headers.remove(http::header::HOST);
   req_headers.insert(http::header::HOST, proxy_addr);

   None  // ignore the return type for this example
}

fn resp_transform(resp: &mut http::Response<Vec<u8>>) {
   let x_header_val = HeaderValue::from_str("Foo Bar").unwrap();
    
    let resp_headers = resp.headers_mut();
    resp_headers.insert("X-HEADER-VAL", x_header_val);
}

fn main() {
    let listen_addr: SocketAddr = "127.0.0.1:8080".parse().unwrap();
    generic_proxy(listen_addr, req_transform, resp_transform);
}

Dependencies

~5.5MB
~112K SLoC