Node.js proxying made simple. Configure proxy middleware with ease for connect, express, browser-sync and many more.
Powered by the popular Nodejitsu http-proxy. 
Proxy /api requests to http://www.example.org
```javascript var express = require('express') var proxy = require('http-proxy-middleware')
var app = express()
app.use('/api', proxy({ target: 'http://www.example.org', changeOrigin: true })) app.listen(3000)
// http://localhost:3000/api/foo/bar -> http://www.example.org/api/foo/bar ```
All http-proxy options can be used, along with some extra http-proxy-middleware options.
:bulb: Tip: Set the option changeOrigin to true for name-based virtual hosted sites.
javascript
$ npm install --save-dev http-proxy-middleware
Proxy middleware configuration.
```javascript var proxy = require('http-proxy-middleware')
var apiProxy = proxy('/api', { target: 'http://www.example.org' }) // _/ ________/ // | | // context options
// 'apiProxy' is now ready to be used as middleware in a server. ```
(full list of http-proxy-middleware configuration options)
javascript
// shorthand syntax for the example above:
var apiProxy = proxy('http://www.example.org/api')
More about the shorthand configuration.
An example with express server.
```javascript // include dependencies var express = require('express') var proxy = require('http-proxy-middleware')
// proxy middleware options var options = { target: 'http://www.example.org', // target host changeOrigin: true, // needed for virtual hosted sites ws: true, // proxy websockets pathRewrite: { '^/api/old-path': '/api/new-path', // rewrite path '^/api/remove/path': '/path' // remove base path }, router: { // 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 (without context) var exampleProxy = proxy(options)
// mount exampleProxy in web server
var app = express()
app.use('/api', exampleProxy)
app.listen(3000)
```
Providing an alternative way to decide which requests should be proxied; In case you are not able to use the server's path parameter to mount the proxy or when you need more flexibility.
RFC 3986 path is used for context matching.
foo://example.com:8042/over/there?name=ferret#nose
\_/ \______________/\_________/ \_________/ \__/
| | | | |
scheme authority path query fragment
path matching
proxy({...}) - matches any path, all requests will be proxied.
proxy('/', {...}) - matches any path, all requests will be proxied.proxy('/api', {...}) - matches paths starting with /api
multiple path matching
proxy(['/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.
proxy('**', {...}) matches any path, all requests will be proxied.proxy('**/*.html', {...}) matches any path which ends with .htmlproxy('/*.html', {...}) matches paths directly under path-absoluteproxy('/api/**/*.html', {...}) matches requests ending with .html in the path of /apiproxy(['/api/**', '/ajax/**'], {...}) combine multiple patternsproxy(['/api/**', '!**/bad.json'], {...}) exclusionNote: In multiple path matching, you cannot use string paths and wildcard paths together.
For full control you can provide a custom function to determine which requests should be proxied or not.
```javascript /* * @return {Boolean} / var filter = function(pathname, req) { return pathname.match('^/api') && req.method === 'GET' }
var apiProxy = proxy(filter, { target: 'http://www.example.org' }) ```
```javascript // rewrite path pathRewrite: {'^/old/api' : '/new/api'}
// remove path pathRewrite: {'^/remove/api' : ''}
// add base path pathRewrite: {'^/' : '/basepath/'}
// custom rewriting pathRewrite: function (path, req) { return path.replace('/api', '/base/api') } ```
option.target for specific requests.``javascript
// Usehostand/orpath` to match requests. First match will be used.
// The order of the configuration matters.
router: {
'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
}
// Custom router function router: function(req) { return 'http://localhost:8004'; } ```
option.logLevel: string, ['debug', 'info', 'warn', 'error', 'silent']. Default: 'info'
option.logProvider: function, modify or replace log provider. Default: console.
javascript
// simple replace
function logProvider(provider) {
// replace the default console log provider.
return require('winston')
}
```javascript // 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.changeOrigin = true instead.option.router instead.Subscribe to http-proxy events:
error event for custom error handling.javascript
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.'
)
}
proxyRes event.javascript
function onProxyRes(proxyRes, req, res) {
proxyRes.headers['x-added'] = 'foobar' // add new header to response
delete proxyRes.headers['x-removed'] // remove header from response
}
proxyReq event.javascript
function onProxyReq(proxyReq, req, res) {
// add custom header to request
proxyReq.setHeader('x-added', 'foobar')
// or log the req
}
proxyReqWs event.javascript
function onProxyReqWs(proxyReq, req, socket, options, head) {
// add custom header
proxyReq.setHeader('X-Special-Proxy-Header', 'foobar')
}
open event.javascript
function onOpen(proxySocket) {
// listen for messages coming FROM the target here
proxySocket.on('data', hybiParseAndLogMessage)
}
close event.
javascript
function onClose(res, socket, head) {
// view disconnected websocket connections
console.log('Client disconnected')
}The following options are provided by the underlying http-proxy library.
path (useful for proxying to proxies)set-cookie headers. Possible values:false (default): disable cookie rewritingcookieDomainRewrite: "new.domain". To remove the domain, use cookieDomainRewrite: ""."*" to match all domains.cookieDomainRewrite: {
"unchanged.domain": "unchanged.domain",
"old.domain": "new.domain",
"*": ""
}set-cookie headers. Possible values:false (default): disable cookie rewritingcookiePathRewrite: "/newPath/". To remove the path, use cookiePathRewrite: "". To set path to root use cookiePathRewrite: "/"."*" to match all paths.
For example, to keep one path unchanged, rewrite one path and remove other paths:
cookiePathRewrite: {
"/unchanged.path/": "/unchanged.path/",
"/old.path/": "/new.path/",
"*": ""
}{host:'www.example.org'})proxyRes event``` 'use strict';
const streamify = require('stream-array'); const HttpProxy = require('http-proxy'); const proxy = new HttpProxy();
module.exports = (req, res, next) => {
proxy.web(req, res, {
target: 'http://localhost:4003/',
buffer: streamify(req.rawBody)
}, next);
}; ```
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.
```javascript proxy('http://www.example.org:8000/api') // proxy('/api', {target: 'http://www.example.org:8000'});
proxy('http://www.example.org:8000/api/books//.json') // proxy('/api/books//**.json', {target: 'http://www.example.org:8000'});
proxy('http://www.example.org:8000/api', { changeOrigin: true }) // proxy('/api', {target: 'http://www.example.org:8000', changeOrigin: true}); ```
If you want to use the server's app.use path parameter to match requests;
Create and mount the proxy without the http-proxy-middleware context parameter:
javascript
app.use('/api', proxy({ target: 'http://www.example.org', changeOrigin: true }))
app.use documentation:
```javascript // verbose api proxy('/', { target: 'http://echo.websocket.org', ws: true })
// shorthand proxy('http://echo.websocket.org', { ws: true })
// shorter shorthand proxy('ws://echo.websocket.org') ```
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.
```javascript var wsProxy = proxy('ws://echo.websocket.org', { changeOrigin: true })
var app = express() app.use(wsProxy)
var server = app.listen(3000) server.on('upgrade', wsProxy.upgrade) // <-- subscribe to http 'upgrade' ```
View and play around with working examples.
View the recipes for common use cases.
http-proxy-middleware is compatible with the following servers:
Sample implementations can be found in the server recipes.
Run the test suite:
```bash
$ npm install
$ npm run lint
$ npm test
$ npm run cover ```
The MIT License (MIT)
Copyright (c) 2015-2018 Steven Chim