diff --git a/examples/url-middleware.js b/examples/url-middleware.js index a625183a7..96f4b813c 100644 --- a/examples/url-middleware.js +++ b/examples/url-middleware.js @@ -1,82 +1,79 @@ -/* - urls-middleware.js: Basic example of middleware in node-http-proxy - - Copyright (c) 2010 Charlie Robbins, Mikeal Rogers, Fedor Indutny, Marak Squires, & Dominic Tarr. - - Permission is hereby granted, free of charge, to any person obtaining - a copy of this software and associated documentation files (the - "Software"), to deal in the Software without restriction, including - without limitation the rights to use, copy, modify, merge, publish, - distribute, sublicense, and/or sell copies of the Software, and to - permit persons to whom the Software is furnished to do so, subject to - the following conditions: - - The above copyright notice and this permission notice shall be - included in all copies or substantial portions of the Software. - - THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, - EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF - MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND - NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE - LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION - OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION - WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. - -*/ - var util = require('util'), colors = require('colors'), http = require('http'), - httpProxy = require('./../lib/node-http-proxy'); - -// -// url proxying middleware example. + httpProxy = require('http-proxy'); + // -// this is not optimised or tested but shows the basic approch to writing a middleware. +// This is an example of a url-routing middleware. +// This is not intended for production use, but rather as +// an example of how to write a middleware. // + function matcher (url, dest) { - var r = new RegExp (url) - + // First, turn the URL into a regex. + // NOTE: Turning user input directly into a Regular Expression is NOT SAFE. + var r = new RegExp(url.replace(/\//, '\\/')); + // This next block of code may look a little confusing. + // It returns a closure (anonymous function) for each URL to be matched, + // storing them in an array - on each request, if the URL matches one that has + // a function stored for it, the function will be called. return function (url) { var m = r(url) - if (!m) return - var path = url.slice(m[0].length) - console.log('proxy:', url, '->', path) - return {url: path, dest: dest} + if (!m) { + return; + } + var path = url.slice(m[0].length); + console.log('proxy:', url, '->', dest); + return {url: path, dest: dest}; } } exports.urls = function (urls) { - - var matchers = [] + // This is the entry point for our middleware. + // 'matchers' is the array of URL matchers, as mentioned above. + var matchers = []; for (var url in urls) { - matchers.push(matcher(url, urls[url])) + // Call the 'matcher' function above, and store the resulting closure. + matchers.push(matcher(url, urls[url])); } + // This closure is returned as the request handler. return function (req, res, next) { // - // in nhp middlewares, `proxy` is the prototype of `next` - // (this means nhp middlewares support both connect API (req, res, next) - // and nhp API (req, res, proxy) + // in node-http-proxy middlewares, `proxy` is the prototype of `next` + // (this means node-http-proxy middlewares support both the connect API (req, res, next) + // and the node-http-proxy API (req, res, proxy) // var proxy = next; - for (var k in matchers) { - var m; - if (m = matchers[k](req.url)) { + // for each URL matcher, try the request's URL. + var m = matchers[k](req.url); + // If it's a match: + if (m) { + // Replace the local URL with the destination URL. req.url = m.url; - return proxy.proxyRequest(req,res, m.dest); + // If routing to a server on another domain, the hostname in the request must be changed. + req.headers.host = m.host; + // Once any changes are taken care of, this line makes the magic happen. + proxy.proxyRequest(req, res, m.dest); } } } } +// Now we set up our proxy. httpProxy.createServer( - exports.urls({'/hello': {port: 9000, host: 'localhost'}}) + // This is where our middlewares go, with any options desired - in this case, + // the list of routes/URLs and their destinations. + exports.urls({ + '/hello': { port: 9000, host: 'localhost' }, + '/charlie': { port: 80, host: 'charlieistheman.com' }, + '/google': { port: 80, host: 'google.com' } + }) ).listen(8000); // -// Target Http Server +// Target Http Server (to listen for requests on 'localhost') // http.createServer( function (req, res) { @@ -85,5 +82,6 @@ http.createServer( res.end(); }).listen(9000); +// And finally, some colored startup output. util.puts('http proxy server'.blue + ' started '.green.bold + 'on port '.blue + '8000'.yellow); -util.puts('http server '.blue + 'started '.green.bold + 'on port '.blue + '9000 '.yellow); +util.puts('http server '.blue + 'started '.green.bold + 'on port '.blue + '9000 '.yellow); \ No newline at end of file