Connect is a middleware layer for Node.js

 Connect is a middleware layer for Node.js   http://senchalabs.github.com/connect

Connect

Connect is an extensible HTTP server framework for node using "plugins" known as middleware.

var connect = require('connect')
var http = require('http')
var app = connect()

// gzip/deflate outgoing responses
var compression = require('compression')
app.use(compression())

// store session state in browser cookie
var cookieSession = require('cookie-session')
app.use(cookieSession({
    keys: ['secret1', 'secret2']
}))

// parse urlencoded request bodies into req.body
var bodyParser = require('body-parser')

app.use(bodyParser.urlencoded())

// respond to all requests
app.use(function(req, res){
  res.end('Hello from Connect!\n');
})

//create node.js http server and listen on port
http.createServer(app).listen(3000)

Getting Started

Connect is a simple framework to glue together various "middleware" to handle requests.

Install Connect

$ npm install connect

Create an app

The main component is a Connect "app". This will store all the middleware added and is, itself, a function.

var app = connect();

Use middleware

The core of Connect is "using" middleware. Middleware are added as a "stack" where incoming requests will execute each middleware one-by-one until a middleware does not call next() within it.

app.use(function middleware1(req, res, next) { // middleware 1 next(); }); app.use(function middleware2(req, res, next) { // middleware 2 next(); });

Mount middleware

The .use() method also takes an optional path string that is matched against the beginning of the incoming request URL. This allows for basic routing.

app.use('/foo', function fooMiddleware(req, res, next) { // req.url starts with "/foo" next(); }); app.use('/bar', function barMiddleware(req, res, next) { // req.url starts with "/bar" next(); });

Error middleware

There are special cases of "error-handling" middleware. There are middleware where the function takes exactly 4 arguments. Errors that occur in the middleware added before the error middleware will invoke this middleware when errors occur.

app.use(function onerror(err, req, res, next) { // an error occurred! });

Create a server from the app

The last step is to actually use the Connect app in a server. The .listen() method is a convenience to start a HTTP server.

var server = app.listen(port);

The app itself is really just a function with three arguments, so it can also be handed to .createServer() in Node.js.

var server = http.createServer(app);

Middleware

These middleware and libraries are officially supported by the Connect/Express team:

• body-parser - previous bodyParser, json, and urlencoded. You may also be interested in:
  • body
  • co-body
  • raw-body
• compression - previously compress
• connect-timeout - previously timeout
• cookie-parser - previously cookieParser
• cookie-session - previously cookieSession
• csurf - previously csrf
• errorhandler - previously error-handler
• express-session - previously session
• method-override - previously method-override
• morgan - previously logger
• response-time - previously response-time
• serve-favicon - previously favicon
• serve-index - previously directory
• serve-static - previously static
• vhost - previously vhost

Most of these are exact ports of their Connect 2.x equivalents. The primary exception is cookie-session.

Some middleware previously included with Connect are no longer supported by the Connect/Express team, are replaced by an alternative module, or should be superseded by a better module. Use one of these alternatives instead:

• cookieParser
  • cookies and keygrip
• limit
  • raw-body
• multipart
  • connect-multiparty
  • connect-busboy
• query
  • qs
• staticCache
  • st
  • connect-static

Checkout http-framework for many other compatible middleware!

Running Tests

npm install npm test

Contributors

https://github.com/senchalabs/connect/graphs/contributors

Node Compatibility

• Connect < 1.x - node 0.2
• Connect 1.x - node 0.4
• Connect < 2.8 - node 0.6
• Connect >= 2.8 < 3 - node 0.8
• Connect >= 3 - node 0.10, 0.12; io.js 1.x, 2.x