Express

Express is largely based on Connect and provides a flexible structure for creating Node.js Web applications.

Express provides a robust set of features for building single-page, multi-page and hybrid Web applications.

The framework is quite successful amongst Node.js developers because it lets developers deal not only with their backend code, but also go down till the HTTP-level of their app, helping them not only control, but boost performance, taking full advantage of the high-powered features Node.js brought to JavaScript development.

Another great design model that developers love(d) about Express is its agnostic nature when it comes to pluggable technology.

Express is basically only the core code, letting developers plug-in their desired extensions for things like: template engines, ORMs, data storage, pre-processors and so on.

There's no doubt that if you ever go into Node.js development, at one point or another you'll end up stumbling upon or working with Express, the framework being one of the most revered, used and loved tools when it comes to server-side JavaScript.

What is new in this release:

• Use content-type to parse Content-Type headers
• Fix "trust proxy" setting to inherit when app is mounted
• Generate ETags for all request responses

What is new in version 4.13.4:

• Use content-type to parse Content-Type headers
• Fix "trust proxy" setting to inherit when app is mounted
• Generate ETags for all request responses

What is new in version 4.13.3:

• Use content-type to parse Content-Type headers
• Fix "trust proxy" setting to inherit when app is mounted
• Generate ETags for all request responses

What is new in version 4.13.1:

• Use content-type to parse Content-Type headers
• Fix "trust proxy" setting to inherit when app is mounted
• Generate ETags for all request responses

What is new in version 4.12.4:

• Use content-type to parse Content-Type headers
• Fix "trust proxy" setting to inherit when app is mounted
• Generate ETags for all request responses

What is new in version 4.12.3:

• Use content-type to parse Content-Type headers
• Fix "trust proxy" setting to inherit when app is mounted
• Generate ETags for all request responses

What is new in version 4.12.0:

• Use content-type to parse Content-Type headers
• Fix "trust proxy" setting to inherit when app is mounted
• Generate ETags for all request responses

What is new in version 4.11.1:

• Fixed:
• Root path disclosure
• Redirect loop in Node.js 0.11.14

What is new in version 4.10.0:

• Add support for app.set('views', array)
• Fix res.send(status) to mention res.sendStatus(status)
• Fix handling of invalid empty URLs
• Use content-disposition module for res.attachment/res.download
• Use path.resolve in view lookup

What is new in version 4.9.6:

• Fixed redirect loop when index file serving disabled.

What is new in version 4.9.1:

• Fixed app.use to accept array of middleware without path.

What is new in version 4.8.6:

• Array parsing fix
• Performance improvements

What is new in version 4.7.2:

• Work-around for V8 generating empty stack traces.

What is new in version 4.5.1:

• Fixed routing regression when altering req.method.

What is new in version 4.4.1:

• Send max-age in Cache-Control in correct format.
• Use escape-html for escaping.

What is new in version 4.3.0:

• Added req.baseUrl to access the path stripped from req.url in routes.
• Fixed behavior of multiple app.VERB for the same path.
• Fixed issue routing requests among sub routers.
• Invoked router.param() only when necessary instead of every match.

What is new in version 4.2.0:

• Fixed req.next when inside router instance
• Included ETag header in HEAD requests
• Keep previous Content-Type for res.jsonp
• Support PURGE method

What is new in version 4.1.2:

• Fixed:
• req.host for IPv6 literals
• res.jsonp error if callback param is object

What is new in version 4.0.0:

• app.route -> app.mountpath when mounting an express app in another express app
• json spaces no longer enabled by default in development
• req.accepts* -> req.accepts*s - i.e. req.acceptsEncoding -> req.acceptsEncodings
• req.params is now an object instead of an array

What is new in version 3.3.6:

• Revert "remove charset from JSON responses.

What is new in version 3.3.4:

• Update Send and Connect.

What is new in version 3.3.3:

• Updated Connect version.

What is new in version 3.3.0:

• Updated Connect.
• Added support for multiple X-Forwarded-Proto values.
• Changed remove charset from json responses.
• Changed return actual booleans from req.accept* functions.

What is new in version 3.2.6:

• Update Connect version.

What is new in version 3.2.5:

• Updated Connect.
• Updated node-cookie.

What is new in version 3.2.0:

• Added "view" constructor setting to override view behavior.
• Added req.acceptsEncoding(name).
• Added req.acceptedEncodings.
• Reverted cookie signature change causing session race conditions.

What is new in version 3.0.6:

• Added HTTP verb methods to Router.
• Updated Connect.

What is new in version 3.0.5:

• Fix for explicitly removing Transfer-Encoding header from 204 and 304 responses.
• Reverted "add 'etag' option".

What is new in version 3.0.4:

• Added escaping of URLs in text/plain in res.redirect() for old browsers interpreting as HTML.
• Changed crc32 module for a more liberal license.
• Updated Connect.

What is new in version 3.0.0 RC 3:

• Updated connect dep.
• Fixed signed cookies to work with connect.cookieParser() ("s:" prefix was missing).
• Fixed res.render() clobbering of "locals".

What is new in version 3.0.0 Beta 7:

• Updated connect dep for send() root normalization regression.

What is new in version 3.3.0 Beta 4:

• Added req.auth
• Added req.range(size)
• Added res.links(obj)
• Added res.send(body, status) support back for backwards compat
• Added .default() support to res.format()
• Added 2xx / 304 check to req.fresh

What is new in version 3.3.0 Beta 3:

• Added hogan --hjs to express
• Added another example to content-negotiation
• Added fresh dep
• Changed: res.send() always checks freshness

What is new in version 2.4.2:

• Revert "removed JSONP stripping" for XSS.

What is new in version 2.4.0:

• Added chainable res.status(code).
• Added res.json(), an explicit version of res.send(obj).
• Added simple web-service example.

What is new in version 2.3.12:

• #express is now on freenode! go join.
• Added req.get(field, param)
• Added links to Japanese documentation
• Added; the express(1) generated app outputs the env
• Added content-negotiation example
• Dependency: connect >= 1.5.1 < 2.0.0
• Fixed view layout bug.
• Fixed; ignore body on 304.

What is new in version 2.3.10:

• Added req.route, exposing the current route.
• Added package.json generation support to express(1).
• Fixed call to app.param() function for optional params.

What is new in version 1.0.3:

• Remove unsafe characters from JSONP callback names.

Requirements:

• Node.js 0.8 or higher
• Connect 2.11.2 or higher