492 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			492 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| # http-proxy-middleware
 | |
| 
 | |
| [](https://travis-ci.org/chimurai/http-proxy-middleware)
 | |
| [](https://coveralls.io/r/chimurai/http-proxy-middleware)
 | |
| [](https://david-dm.org/chimurai/http-proxy-middleware#info=dependencies)
 | |
| [](https://snyk.io/test/npm/http-proxy-middleware)
 | |
| [](https://github.com/prettier/prettier)
 | |
| 
 | |
| Node.js proxying made simple. Configure proxy middleware with ease for [connect](https://github.com/senchalabs/connect), [express](https://github.com/strongloop/express), [browser-sync](https://github.com/BrowserSync/browser-sync) and [many more](#compatible-servers).
 | |
| 
 | |
| Powered by the popular Nodejitsu [`http-proxy`](https://github.com/nodejitsu/node-http-proxy). [](https://github.com/nodejitsu/node-http-proxy)
 | |
| 
 | |
| ## TL;DR
 | |
| 
 | |
| 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](https://github.com/nodejitsu/node-http-proxy#options) can be used, along with some extra `http-proxy-middleware` [options](#options).
 | |
| 
 | |
| :bulb: **Tip:** Set the option `changeOrigin` to `true` for [name-based virtual hosted sites](http://en.wikipedia.org/wiki/Virtual_hosting#Name-based).
 | |
| 
 | |
| ## Table of Contents
 | |
| 
 | |
| <!-- MarkdownTOC autolink=true bracket=round depth=2 -->
 | |
| 
 | |
| - [Install](#install)
 | |
| - [Core concept](#core-concept)
 | |
| - [Example](#example)
 | |
| - [Context matching](#context-matching)
 | |
| - [Options](#options)
 | |
|   - [http-proxy-middleware options](#http-proxy-middleware-options)
 | |
|   - [http-proxy events](#http-proxy-events)
 | |
|   - [http-proxy options](#http-proxy-options)
 | |
| - [Shorthand](#shorthand)
 | |
|   - [app.use\(path, proxy\)](#appusepath-proxy)
 | |
| - [WebSocket](#websocket)
 | |
|   - [External WebSocket upgrade](#external-websocket-upgrade)
 | |
| - [Working examples](#working-examples)
 | |
| - [Recipes](#recipes)
 | |
| - [Compatible servers](#compatible-servers)
 | |
| - [Tests](#tests)
 | |
| - [Changelog](#changelog)
 | |
| - [License](#license)
 | |
| 
 | |
| <!-- /MarkdownTOC -->
 | |
| 
 | |
| ## Install
 | |
| 
 | |
| ```javascript
 | |
| $ npm install --save-dev http-proxy-middleware
 | |
| ```
 | |
| 
 | |
| ## Core concept
 | |
| 
 | |
| Proxy middleware configuration.
 | |
| 
 | |
| #### proxy([context,] config)
 | |
| 
 | |
| ```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.
 | |
| ```
 | |
| 
 | |
| - **context**: Determine which requests should be proxied to the target host.
 | |
|   (more on [context matching](#context-matching))
 | |
| - **options.target**: target host to proxy to. _(protocol + host)_
 | |
| 
 | |
| (full list of [`http-proxy-middleware` configuration options](#options))
 | |
| 
 | |
| #### proxy(uri [, config])
 | |
| 
 | |
| ```javascript
 | |
| // shorthand syntax for the example above:
 | |
| var apiProxy = proxy('http://www.example.org/api')
 | |
| ```
 | |
| 
 | |
| More about the [shorthand configuration](#shorthand).
 | |
| 
 | |
| ## Example
 | |
| 
 | |
| 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)
 | |
| ```
 | |
| 
 | |
| ## Context matching
 | |
| 
 | |
| Providing an alternative way to decide which requests should be proxied; In case you are not able to use the server's [`path` parameter](http://expressjs.com/en/4x/api.html#app.use) to mount the proxy or when you need more flexibility.
 | |
| 
 | |
| [RFC 3986 `path`](https://tools.ietf.org/html/rfc3986#section-3.3) 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](https://www.npmjs.com/package/micromatch) or [glob](https://www.npmjs.com/package/glob) for more globbing examples.
 | |
| 
 | |
|   - `proxy('**', {...})` matches any path, all requests will be proxied.
 | |
|   - `proxy('**/*.html', {...})` matches any path which ends with `.html`
 | |
|   - `proxy('/*.html', {...})` matches paths directly under path-absolute
 | |
|   - `proxy('/api/**/*.html', {...})` matches requests ending with `.html` in the path of `/api`
 | |
|   - `proxy(['/api/**', '/ajax/**'], {...})` combine multiple patterns
 | |
|   - `proxy(['/api/**', '!**/bad.json'], {...})` exclusion
 | |
| 
 | |
|   **Note**: In multiple path matching, you cannot use string paths and wildcard paths together.
 | |
| 
 | |
| - **custom matching**
 | |
| 
 | |
|   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' })
 | |
|   ```
 | |
| 
 | |
| ## Options
 | |
| 
 | |
| ### http-proxy-middleware options
 | |
| 
 | |
| - **option.pathRewrite**: object/function, rewrite target's url path. Object-keys will be used as _RegExp_ to match paths.
 | |
| 
 | |
|   ```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.router**: object/function, re-target `option.target` for specific requests.
 | |
| 
 | |
|   ```javascript
 | |
|   // Use `host` and/or `path` 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
 | |
|   }
 | |
|   ```
 | |
| 
 | |
| - (DEPRECATED) **option.proxyHost**: Use `option.changeOrigin = true` instead.
 | |
| - (DEPRECATED) **option.proxyTable**: Use `option.router` instead.
 | |
| 
 | |
| ### http-proxy events
 | |
| 
 | |
| Subscribe to [http-proxy events](https://github.com/nodejitsu/node-http-proxy#listening-for-proxy-events):
 | |
| 
 | |
| - **option.onError**: function, subscribe to http-proxy's `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.'
 | |
|     )
 | |
|   }
 | |
|   ```
 | |
| 
 | |
| - **option.onProxyRes**: function, subscribe to http-proxy's `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
 | |
|   }
 | |
|   ```
 | |
| 
 | |
| - **option.onProxyReq**: function, subscribe to http-proxy's `proxyReq` event.
 | |
| 
 | |
|   ```javascript
 | |
|   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.
 | |
| 
 | |
|   ```javascript
 | |
|   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.
 | |
| 
 | |
|   ```javascript
 | |
|   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.
 | |
|   ```javascript
 | |
|   function onClose(res, socket, head) {
 | |
|     // view disconnected websocket connections
 | |
|     console.log('Client disconnected')
 | |
|   }
 | |
|   ```
 | |
| 
 | |
| ### http-proxy options
 | |
| 
 | |
| The following options are provided by the underlying [http-proxy](https://github.com/nodejitsu/node-http-proxy#options) library.
 | |
| 
 | |
| - **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](http://nodejs.org/api/https.html#https_class_https_agent) and [http agent](http://nodejs.org/api/http.html#http_class_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**: true/false, 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 (note: you will have to append / manually if required).
 | |
| - **option.localAddress** : Local interface string to bind for outgoing connections
 | |
| - **option.changeOrigin**: true/false, Default: false - changes the origin of the host header to the target URL
 | |
| - **option.preserveHeaderKeyCase**: true/false, Default: false - specify whether you want to keep letter case of response header key
 | |
| - **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.cookieDomainRewrite**: rewrites domain of `set-cookie` headers. Possible values:
 | |
|   - `false` (default): disable cookie rewriting
 | |
|   - String: new domain, for example `cookieDomainRewrite: "new.domain"`. To remove the domain, use `cookieDomainRewrite: ""`.
 | |
|   - Object: mapping of domains to new domains, use `"*"` to match all domains.  
 | |
|     For example keep one domain unchanged, rewrite one domain and remove other domains:
 | |
|     ```
 | |
|     cookieDomainRewrite: {
 | |
|       "unchanged.domain": "unchanged.domain",
 | |
|       "old.domain": "new.domain",
 | |
|       "*": ""
 | |
|     }
 | |
|     ```
 | |
| - **option.cookiePathRewrite**: rewrites path of `set-cookie` headers. Possible values:
 | |
|   - `false` (default): disable cookie rewriting
 | |
|   - String: new path, for example `cookiePathRewrite: "/newPath/"`. To remove the path, use `cookiePathRewrite: ""`. To set path to root use `cookiePathRewrite: "/"`.
 | |
|   - Object: mapping of paths to new paths, use `"*"` 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/",
 | |
|       "*": ""
 | |
|     }
 | |
|     ```
 | |
| - **option.headers**: object, adds [request headers](https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#Request_fields). (Example: `{host:'www.example.org'}`)
 | |
| - **option.proxyTimeout**: timeout (in millis) when proxy receives no response from target
 | |
| - **option.timeout**: timeout (in millis) for incoming requests
 | |
| - **option.followRedirects**: true/false, Default: false - specify whether you want to follow redirects
 | |
| - **option.selfHandleResponse** true/false, if set to true, none of the webOutgoing passes are called and it's your responsibility to appropriately return the response by listening and acting on the `proxyRes` event
 | |
| - **option.buffer**: stream of data to send as the request body. Maybe you have some middleware that consumes the request stream before proxying it on e.g. If you read the body of a request into a field called 'req.rawbody' you could restream this field in the buffer option:
 | |
| 
 | |
|   ```
 | |
|   '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);
 | |
| 
 | |
|   };
 | |
|   ```
 | |
| 
 | |
| ## 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.
 | |
| 
 | |
| ```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});
 | |
| ```
 | |
| 
 | |
| ### app.use(path, proxy)
 | |
| 
 | |
| 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:
 | |
| 
 | |
| - express: http://expressjs.com/en/4x/api.html#app.use
 | |
| - connect: https://github.com/senchalabs/connect#mount-middleware
 | |
| 
 | |
| ## WebSocket
 | |
| 
 | |
| ```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')
 | |
| ```
 | |
| 
 | |
| ### 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.
 | |
| 
 | |
| ```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'
 | |
| ```
 | |
| 
 | |
| ## Working examples
 | |
| 
 | |
| View and play around with [working examples](https://github.com/chimurai/http-proxy-middleware/tree/master/examples).
 | |
| 
 | |
| - Browser-Sync ([example source](https://github.com/chimurai/http-proxy-middleware/tree/master/examples/browser-sync/index.js))
 | |
| - express ([example source](https://github.com/chimurai/http-proxy-middleware/tree/master/examples/express/index.js))
 | |
| - connect ([example source](https://github.com/chimurai/http-proxy-middleware/tree/master/examples/connect/index.js))
 | |
| - WebSocket ([example source](https://github.com/chimurai/http-proxy-middleware/tree/master/examples/websocket/index.js))
 | |
| 
 | |
| ## Recipes
 | |
| 
 | |
| View the [recipes](https://github.com/chimurai/http-proxy-middleware/tree/master/recipes) for common use cases.
 | |
| 
 | |
| ## Compatible servers
 | |
| 
 | |
| `http-proxy-middleware` is compatible with the following servers:
 | |
| 
 | |
| - [connect](https://www.npmjs.com/package/connect)
 | |
| - [express](https://www.npmjs.com/package/express)
 | |
| - [browser-sync](https://www.npmjs.com/package/browser-sync)
 | |
| - [lite-server](https://www.npmjs.com/package/lite-server)
 | |
| - [grunt-contrib-connect](https://www.npmjs.com/package/grunt-contrib-connect)
 | |
| - [grunt-browser-sync](https://www.npmjs.com/package/grunt-browser-sync)
 | |
| - [gulp-connect](https://www.npmjs.com/package/gulp-connect)
 | |
| - [gulp-webserver](https://www.npmjs.com/package/gulp-webserver)
 | |
| 
 | |
| Sample implementations can be found in the [server recipes](https://github.com/chimurai/http-proxy-middleware/tree/master/recipes/servers.md).
 | |
| 
 | |
| ## Tests
 | |
| 
 | |
| Run the test suite:
 | |
| 
 | |
| ```bash
 | |
| # install dependencies
 | |
| $ npm install
 | |
| 
 | |
| # linting
 | |
| $ npm run lint
 | |
| 
 | |
| # unit tests
 | |
| $ npm test
 | |
| 
 | |
| # code coverage
 | |
| $ npm run cover
 | |
| ```
 | |
| 
 | |
| ## Changelog
 | |
| 
 | |
| - [View changelog](https://github.com/chimurai/http-proxy-middleware/blob/master/CHANGELOG.md)
 | |
| 
 | |
| ## License
 | |
| 
 | |
| The MIT License (MIT)
 | |
| 
 | |
| Copyright (c) 2015-2018 Steven Chim
 |