[examples] updated bodyDecoder middleware example

Author: cronopio

examples/helpers/store.js

@@ -0,0 +1,64 @@
+
+//
+// just to make these example a little bit interesting, 
+// make a little key value store with an http interface
+// (see couchbd for a grown-up version of this)
+//
+// API:
+// GET / 
+// retrive list of keys
+//
+// GET /[url]
+// retrive object stored at [url]
+// will respond with 404 if there is nothing stored at [url]
+//
+// POST /[url]
+// 
+// JSON.parse the body and store it under [url]
+// will respond 400 (bad request) if body is not valid json.
+//
+// TODO: cached map-reduce views and auto-magic sharding.
+//
+var Store = module.exports = function Store () {
+  this.store = {};
+};
+
+Store.prototype = {
+  get: function (key) {
+    return this.store[key]
+  },
+  set: function (key, value) {
+    return this.store[key] = value
+  },
+  handler:function () {
+    var store = this
+    return function (req, res) {
+      function send (obj, status) {
+        res.writeHead(200 || status,{'Content-Type': 'application/json'})
+        res.write(JSON.stringify(obj) + '\n')
+        res.end()
+      }
+      var url = req.url.split('?').shift()
+      if (url === '/') {
+        console.log('get index')
+        return send(Object.keys(store.store))
+      } else if (req.method == 'GET') {
+        var obj = store.get (url)
+        send(obj || {error: 'not_found', url: url}, obj ? 200 : 404)
+      } else {
+        //post: buffer body, and parse.
+        var body = '', obj
+        req.on('data', function (c) { body += c})
+        req.on('end', function (c) {
+          try {
+            obj = JSON.parse(body)
+          } catch (err) {
+            return send (err, 400)
+          }
+          store.set(url, obj)
+          send({ok: true})
+        })
+      } 
+    }
+  }
+}

examples/middleware/bodyDecoder-middleware.js

@@ -0,0 +1,119 @@
+/*
+  bodyDecoder-middleware.js: Basic example of `connect.bodyParser()` middleware in node-http-proxy
+
+  Copyright (c) Nodejitsu 2013
+
+  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 http = require('http'),
+    connect = require('connect'),
+    request = require('request'),
+    colors = require('colors'),
+    util = require('util'),
+    Store = require('../helpers/store'),
+    httpProxy = require('../../lib/http-proxy'),
+    proxy = httpProxy.createProxyServer({});
+
+http.createServer(new Store().handler()).listen(7531, function () {
+  util.puts('http '.blue + 'greetings '.green + 'server'.blue + ' started '.green.bold + 'on port '.blue + '7531'.yellow);
+//try these commands:
+// get index:
+// curl localhost:7531
+// []
+//
+// get a doc:
+// curl localhost:7531/foo
+// {"error":"not_found"}
+//
+// post an doc:
+// curl -X POST localhost:7531/foo -d '{"content": "hello", "type": "greeting"}'
+// {"ok":true}
+//
+// get index (now, not empty)
+// curl localhost:7531
+// ["/foo"]
+//
+// get doc 
+// curl localhost:7531/foo
+// {"content": "hello", "type": "greeting"}
+
+//
+// now, suppose we wanted to direct all objects where type == "greeting" to a different store 
+// than where type == "insult"
+//
+// we can use connect connect-bodyDecoder and some custom logic to send insults to another Store.
+
+//insult server:
+
+  http.createServer(new Store().handler()).listen(2600, function () {
+    util.puts('http '.blue + 'insults '.red + 'server'.blue + ' started '.green.bold + 'on port '.blue + '2600'.yellow);
+
+  //greetings -> 7531, insults-> 2600 
+
+  // now, start a proxy server.
+
+    //don't worry about incoming contont type
+    //bodyParser.parse[''] = JSON.parse
+
+    connect.createServer(
+      //refactor the body parser and re-streamer into a separate package
+      connect.bodyParser(),
+      //body parser absorbs the data and end events before passing control to the next
+      // middleware. if we want to proxy it, we'll need to re-emit these events after 
+      //passing control to the middleware.
+      require('connect-restreamer')(),
+      function (req, res) {
+        //if your posting an obect which contains type: "insult"
+        //it will get redirected to port 2600.
+        //normal get requests will go to 7531 nad will not return insults.
+        var port = (req.body && req.body.type === 'insult' ? 2600 : 7531)
+        proxy.web(req, res, { target: { host: 'localhost', port: port }});
+      }
+    ).listen(1337, function () {
+      util.puts('http proxy server'.blue + ' started '.green.bold + 'on port '.blue + '1337'.yellow);
+      //bodyParser needs content-type set to application/json
+      //if we use request, it will set automatically if we use the 'json:' field.
+      function post (greeting, type) {
+        request.post({
+          url: 'http://localhost:1337/' + greeting,
+          json: {content: greeting, type: type || "greeting"}
+        })
+      }
+      post("hello")
+      post("g'day")
+      post("kiora")
+      post("houdy")
+      post("java", "insult")
+
+      //now, the insult should have been proxied to 2600
+      
+      //curl localhost:2600
+      //["/java"]
+
+      //but the greetings will be sent to 7531
+
+      //curl localhost:7531
+      //["/hello","/g%27day","/kiora","/houdy"]
+
+    })
+  })
+});

examples/package.json

@@ -6,6 +6,8 @@
     "colors": "~0.6.2",
     "socket.io": "~0.9.16",
     "socket.io-client": "~0.9.16",
-    "connect": "~2.11.0"
+    "connect": "~2.11.0",
+    "request": "~2.27.0",
+    "connect-restreamer": "~1.0.0"
   }
 }