http-proxy-middleware
Node.js proxying made simple. Configure proxy middleware with ease for connect, express and browser-sync.
Powered by the popular Nodejitsu http-proxy
.
Install
$ npm install --save-dev http-proxy-middleware
Core concept
Configure the proxy middleware.
var proxyMiddleware = require('http-proxy-middleware');
var proxy = proxyMiddleware('/api', {target: 'http://www.example.org'});
// \____/ \________________________________/
// | |
// context options
// 'proxy' is now ready to be used in a server.
- context: matches provided context against request-urls' path.
Matching requests will be proxied to the target host.
Example:
'/api'
or['/api', '/ajax']
. (more about context matching) - options.target: target host to proxy to. Check out available proxy middleware options.
// shorthand syntax for the example above:
var proxy = proxyMiddleware('http://www.example.org/api');
More about the shorthand configuration.
Example
An example with express server.
// include dependencies
var express = require('express');
var proxyMiddleware = require('http-proxy-middleware');
// configure proxy middleware context
var context = '/api'; // requests with this path will be proxied
// configure proxy middleware options
var options = {
target: 'http://www.example.org', // target host
changeOrigin: true, // needed for virtual hosted sites
ws: true, // proxy websockets
pathRewrite: {
'^/old/api' : '/new/api', // rewrite path
'^/remove/api' : '/api' // remove path
},
proxyTable: {
// when request.headers.host == 'dev.localhost:3000',
// override target 'http://www.example.org' to 'http://localhost:8000'
'dev.localhost:3000' : 'http://localhost:8000'
}
};
// create the proxy
var proxy = proxyMiddleware(context, options);
// use the configured `proxy` in web server
var app = express();
app.use(proxy);
app.listen(3000);
Check out working examples.
Tip: For name-based virtual hosted sites, you'll need to use the option changeOrigin
and set it to true
.
Context matching
http-proxy-middleware offers several ways to decide which requests should be proxied. Request URL's path-absolute and query will be used for context matching .
-
path matching
'/'
- matches any path, all requests will be proxied.'/api'
- matches paths starting with/api
-
multiple path matching
['/api', '/ajax', '/someotherpath']
-
wildcard path matching For fine-grained control you can use wildcard matching. Glob pattern matching is done by micromatch. Visit micromatch or glob for more globbing examples.
'**'
matches any path, all requests will be proxied.'**/*.html'
matches any path which ends with.html
'/*.html'
matches paths directly under path-absolute'/api/**/*.html'
matches requests ending with.html
in the path of/api
['/api/**', '/ajax/**']
combine multiple patterns['/api/**', '!**/bad.json']
exclusion
Shorthand
Use the shorthand syntax when verbose configuration is not needed. The context
and option.target
will be automatically configured when shorthand is used. Options can still be used if needed.
proxyMiddleware('http://www.example.org:8000/api');
// proxyMiddleware('/api', {target: 'http://www.example.org:8000'});
proxyMiddleware('http://www.example.org:8000/api/books/*/**.json');
// proxyMiddleware('/api/books/*/**.json', {target: 'http://www.example.org:8000'});
proxyMiddleware('http://www.example.org:8000/api', {changeOrigin:true});
// proxyMiddleware('/api', {target: 'http://www.example.org:8000', changeOrigin: true});
WebSocket
// verbose api
proxyMiddleware('/', {target:'http://echo.websocket.org', ws:true});
// shorthand
proxyMiddleware('http://echo.websocket.org', {ws:true});
// shorter shorthand
proxyMiddleware('ws://echo.websocket.org');
External WebSocket upgrade
In the previous WebSocket examples, http-proxy-middleware relies on a initial http request in order to listen to the http upgrade
event. If you need to proxy WebSockets without the initial http request, you can subscribe to the server's http upgrade
event manually.
var proxy = proxyMiddleware('ws://echo.websocket.org', {changeOrigin:true});
var app = express();
app.use(proxy);
var server = app.listen(3000);
server.on('upgrade', proxy.upgrade); // <-- subscribe to http 'upgrade'
Options
-
option.pathRewrite: object, rewrite target's url path. Object-keys will be used as RegExp to match paths.
// rewrite path pathRewrite: {"^/old/api" : "/new/api"} // remove path pathRewrite: {"^/remove/api" : ""} // add base path pathRewrite: {"^/" : "/basepath/"}
-
option.proxyTable: object, re-target
option.target
based on the request headerhost
parameter.host
can be used in conjunction withpath
. Only one instance of the proxy will be used. The order of the configuration matters.proxyTable: { "integration.localhost:3000" : "http://localhost:8001", // host only "staging.localhost:3000" : "http://localhost:8002", // host only "localhost:3000/api" : "http://localhost:8003", // host + path "/rest" : "http://localhost:8004" // path only }
-
option.logLevel: string, ['debug', 'info', 'warn', 'error', 'silent']. Default: 'info'
-
option.logProvider: function, modify or replace log provider. Default:
console
.// simple replace function logProvider(provider) { // replace the default console log provider. return require('winston'); }
// verbose replacement function logProvider(provider) { var logger = new (require('winston').Logger)(); var myCustomProvider = { log: logger.log, debug: logger.debug, info: logger.info, warn: logger.warn, error: logger.error } return myCustomProvider; }
-
option.onError: function, subscribe to http-proxy's
error
event for custom error handling.function onError(err, req, res) { res.writeHead(500, { 'Content-Type': 'text/plain' }); res.end('Something went wrong. And we are reporting a custom error message.'); }
-
option.onProxyRes: function, subscribe to http-proxy's
proxyRes
event.function onProxyRes(proxyRes, req, res) { proxyRes.headers['x-added'] = 'foobar'; // add new header to response delete proxyRes.headers['x-removed']; // remove header from response }
-
option.onProxyReq: function, subscribe to http-proxy's
proxyReq
event.function onProxyReq(proxyReq, req, res) { // add custom header to request proxyReq.setHeader('x-added', 'foobar'); // or log the req }
-
option.onProxyReqWs: function, subscribe to http-proxy's
proxyReqWs
event.function onProxyReqWs(proxyReq, req, socket, options, head) { // add custom header proxyReq.setHeader('X-Special-Proxy-Header', 'foobar'); }
-
option.onOpen: function, subscribe to http-proxy's
open
event.function onOpen(proxySocket) { // listen for messages coming FROM the target here proxySocket.on('data', hybiParseAndLogMessage); }
-
option.onClose: function, subscribe to http-proxy's
close
event.function onClose(res, socket, head) { // view disconnected websocket connections console.log('Client disconnected'); }
-
(DEPRECATED) option.proxyHost: Use
option.changeOrigin = true
instead.
The following options are provided by the underlying http-proxy.
- option.target: url string to be parsed with the url module
- option.forward: url string to be parsed with the url module
- option.agent: object to be passed to http(s).request (see Node's https agent and http agent objects)
- option.ssl: object to be passed to https.createServer()
- option.ws: true/false: if you want to proxy websockets
- option.xfwd: true/false, adds x-forward headers
- option.secure: true/false, if you want to verify the SSL Certs
- option.toProxy: passes the absolute URL as the
path
(useful for proxying to proxies) - option.prependPath: true/false, Default: true - specify whether you want to prepend the target's path to the proxy path>
- option.ignorePath: true/false, Default: false - specify whether you want to ignore the proxy path of the incoming request>
- option.localAddress : Local interface string to bind for outgoing connections
- option.changeOrigin: true/false, adds host to request header.
- option.auth : Basic authentication i.e. 'user:password' to compute an Authorization header.
- option.hostRewrite: rewrites the location hostname on (301/302/307/308) redirects.
- option.autoRewrite: rewrites the location host/port on (301/302/307/308) redirects based on requested host/port. Default: false.
- option.protocolRewrite: rewrites the location protocol on (301/302/307/308) redirects to 'http' or 'https'. Default: null.
- option.headers: object, adds request headers. (Example:
{host:'www.example.org'}
)
Recipes
View the recipes for common use cases.
More Examples
To run and view the proxy examples, clone the http-proxy-middleware repo and install the dependencies:
$ git clone https://github.com/chimurai/http-proxy-middleware.git
$ cd http-proxy-middleware
$ npm install
Run the example:
$ node examples/connect
Or just explore the proxy examples' sources:
examples/connect
- connect proxy exampleexamples/express
- express proxy exampleexamples/browser-sync
- browser-sync proxy exampleexamples/websocket
- websocket proxy example with express
Compatible servers
http-proxy-middleware is compatible with the following servers:
Tests
To run the test suite, first install the dependencies, then run:
# install dependencies
$ npm install
# unit tests
$ npm test
# code coverage
$ npm run cover
Changelog
License
The MIT License (MIT)
Copyright (c) 2015 Steven Chim