Proxy with express.js

request has been deprecated as of February 2020, I'll leave the answer below for historical reasons, but please consider moving to an alternative listed in this issue.

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I did something similar but I used request instead:

var request = require('request');app.get('/', function(req,res) {  //modify the url in any way you want  var newurl = 'http://google.com/';  request(newurl).pipe(res);});

I hope this helps, took me a while to realize that I could do this :)

I found a shorter and very straightforward solution which works seamlessly, and with authentication as well, using express-http-proxy:

const url = require('url');const proxy = require('express-http-proxy');// New hostname+path as specified by question:const apiProxy = proxy('other_domain.com:3000/BLABLA', {    proxyReqPathResolver: req => url.parse(req.baseUrl).path});

And then simply:

app.use('/api/*', apiProxy);

Note: as mentioned by @MaxPRafferty, use req.originalUrl in place of baseUrl to preserve the querystring:

    forwardPath: req => url.parse(req.baseUrl).path

Update: As mentioned by Andrew (thank you!), there's a ready-made solution using the same principle:

npm i --save http-proxy-middleware

And then:

const proxy = require('http-proxy-middleware')var apiProxy = proxy('/api', {target: 'http://www.example.org/api'});app.use(apiProxy)

Documentation: http-proxy-middleware on Github

I know I'm late to join this party, but I hope this helps someone.

You want to use http.request to create a similar request to the remote API and return its response.

Something like this:

const http = require('http');// or use import http from 'http';/* your app config here */app.post('/api/BLABLA', (oreq, ores) => {  const options = {    // host to forward to    host: 'www.google.com',    // port to forward to    port: 80,    // path to forward to    path: '/api/BLABLA',    // request method    method: 'POST',    // headers to send    headers: oreq.headers,  };  const creq = http    .request(options, pres => {      // set encoding      pres.setEncoding('utf8');      // set http status code based on proxied response      ores.writeHead(pres.statusCode);      // wait for data      pres.on('data', chunk => {        ores.write(chunk);      });      pres.on('close', () => {        // closed, let's end client request as well        ores.end();      });      pres.on('end', () => {        // finished, let's finish client request as well        ores.end();      });    })    .on('error', e => {      // we got an error      console.log(e.message);      try {        // attempt to set error message and http status        ores.writeHead(500);        ores.write(e.message);      } catch (e) {        // ignore      }      ores.end();    });  creq.end();});

Notice: I haven't really tried the above, so it might contain parse errors hopefully this will give you a hint as to how to get it to work.