A graceful error handler for Express applications. 

ericelliott

express-error-handler

var mixIn = require('mout/object/mixIn'),

  statusCodes = require('http').STATUS_CODES,

   * Return true if the error status represents

   * a client error that should not trigger a

  isClientError = function isClientError(status) {

    return (status >= 400 && status <= 499);

   * Attempt a graceful shutdown, and then time

   * out if the connections fail to drain in time.

   * @param  {object} o.server server object

   * @param  {object} o.timeout timeout in ms

   * @param  {function} exit - force kill function

    // We need to kill the server process so

    // the app can repair itself. Your process 

    // should be monitored in production and

    // That can be accomplished with modules

    if (o.server && typeof o.server.close ===

    // Just in case the server.close() callback

    // never fires, this will wait for a timeout

    // and then terminate. Users can override

    // this function by passing options.shutdown:

   * Take an error status and return a route that

   * sends an error with the appropriate status

   * @return {function} Express route handler

  httpError = function httpError (status, message) {

    return function httpErr(req, res, next) {

  sendFile = function sendFile (staticFile, res) {

    var filePath = path.resolve(staticFile),

      stream = fs.createReadStream(filePath);

  send = function send(statusCode, err, res, o) {

 * @param {object} [options.handlers] Custom

 *        handlers for specific status codes.

 * @param {object} [options.views] View files to 

 *        render in response to specific status 

 * @param {object} [options.static] Static files 

 *        to send in response to specific status 

 * @param {number} [options.timeout] Delay 

 *        attempt and the forced shutdown

 * @param {number} [options.exitStatus] Custom 

 * @param {object} [options.server] The app server

 * @param {function} [options.shutdown] An

 *        alternative shutdown function if the

 * @param {function} serializer A function to

 *        customize the JSON error object.

 *        Usage: serializer(err) return errObj

  "description": "A graceful error handler for Express applications.",

    "url": "git@github.com:dilvie/express-error-handler.git"

    "url": "https://github.com/dilvie/express-error-handler/issues"

A graceful error handler for Express applications. This also patches a DOS exploit where users can manually trigger bad request errors that shut down your app.

  errorHandler = require('../error-handler.js'),

app.get('/error', function createError(req,

// Create the server object that we can pass

// Respond to errors and conditionally shut

// down the server. Pass in the server object

app.use( errorHandler({server: server}) );

  console.log('Listening on port ' + port);

Here are the parameters you can pass into the `errorHandler()` middleware:

* @param {object} [options.handlers] Custom handlers for specific status codes.

* @param {object} [options.views] View files to render in response to specific status codes. Specify a default with `options.views.default`

* @param {object} [options.static] Static files to send in response to specific status codes. Specify a default with options.static.default.

* @param {number} [options.timeout] Delay between the graceful shutdown attempt and the forced shutdown timeout.

* @param {number} [options.exitStatus] Custom process exit status code.

* @param {object} [options.server] The app server object for graceful shutdowns.

* @param {function} [options.shutdown] An alternative shutdown function if the graceful shutdown fails.

* @param {function} serializer a function to customize the JSON error object. Usage: serializer(err) return errObj

* @param {function} framework Either 'express' (default) or 'restify'.

* @return {function} errorHandler Express error handling middleware.

`express-error-handler` lets you specify custom templates, static pages, or error handlers for your errors. It also does other useful error-handling things that every app should implement, like protect against 4xx error DOS attacks, and graceful shutdown on unrecoverable errors. Here's how you do what you're asking for:

var errorHandler = require('express-error-handler'),

Written by [Eric Elliott](http://ericelliottjs.com/) for the book, ["Programming JavaScript Applications"](http://www.amazon.com/gp/product/1491950293?ie=UTF8&camp=213733&creative=393185&creativeASIN=1491950293&linkCode=shr&tag=eejs-20&linkId=TSFLZ3FJX2X4WZ5H) (O'Reilly)

* [Nam Nguyen](https://github.com/gdbtek) for bringing the Express DOS exploit to my attention.

* [Samuel Reed](https://github.com/strml) for helpful suggestions.

		@@ -56,5 +56,10 @@ /**
		'function') {
		o.server.close(function () {
		try {
		o.server.close(function () {
		process.exit(o.exitStatus);
		});
		}
		finally {
		process.exit(o.exitStatus);
		});
		}
		}
		@@ -61,0 +66,0 @@

		{
		"name": "express-error-handler",
		"version": "0.6.0",
		"version": "1.0.0",
		"description": "A graceful error handler for Express applications.",
		@@ -5,0 +5,0 @@ "main": "error-handler.js",

Fixed alerts

Improved metrics

		express-error-handler
		=====================

		A graceful error handler for Express applications.
		A graceful error handler for Express applications. This also patches a DOS exploit where users can manually trigger bad request errors that shut down your app.


		## Quick start:
		@@ -160,5 +161,7 @@

		## Thanks
		## Credit and Thanks

		Written by [Eric Elliott](http://ericelliottjs.com/) for the book, ["Programming JavaScript Applications"](http://www.amazon.com/gp/product/1491950293?ie=UTF8&camp=213733&creative=393185&creativeASIN=1491950293&linkCode=shr&tag=eejs-20&linkId=TSFLZ3FJX2X4WZ5H) (O'Reilly)

		* [Nam Nguyen](https://github.com/gdbtek) for bringing the Express DOS exploit to my attention.
		* [Samuel Reed](https://github.com/strml) for helpful suggestions.