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errorhandler
Advanced tools
Development-only error handler middleware
$ npm install errorhandler
var errorhandler = require('errorhandler')
Create new middleware to handle errors and respond with content negotiation. This middleware is only intended to be used in a development environment, as the full error stack traces will be sent back to the client when an error occurs.
Error handler accepts these properties in the options object.
Provide a function to be called with the error and a string representation of
the error. Can be used to write the error to any desired location, or set to
false to only send the error back in the response. Called as
log(err, str, req, res) where err is the Error object, str is a string
representation of the error, req is the request object and res is the
response object (note, this function is invoked after the response has been
written).
The default value for this option is true unless process.env.NODE_ENV === 'test'.
Possible values:
true: Log errors using console.error(str).false: Only send the error back in the response.Basic example of adding this middleware as the error handler only in development
with connect (express also can be used in this example).
var connect = require('connect')
var errorhandler = require('errorhandler')
var app = connect()
if (process.env.NODE_ENV === 'development') {
// only use in development
app.use(errorhandler())
}
Sometimes you may want to output the errors to a different location than STDERR during development, like a system notification, for example.
var connect = require('connect')
var errorhandler = require('errorhandler')
var notifier = require('node-notifier')
var app = connect()
if (process.env.NODE_ENV === 'development') {
// only use in development
app.use(errorhandler({log: errorNotification}))
}
function errorNotification(err, str, req) {
var title = 'Error in ' + req.method + ' ' + req.url
notifier.notify({
title: title,
message: str
})
}
This package is a drop-in replacement for Express's default error handler. It automatically catches errors from async routes and passes them to your error handlers. It does not provide the same level of detail for stack traces as errorhandler, but it is useful for handling errors in asynchronous code.
This is an error handler for use with Express.js applications, similar to errorhandler. It is designed to provide a more secure, production-ready error handling solution. It can be configured to hide or show stack traces and error details based on the environment.
FAQs
Development-only error handler middleware
The npm package errorhandler receives a total of 1,941,497 weekly downloads. As such, errorhandler popularity was classified as popular.
We found that errorhandler demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 6 open source maintainers collaborating on the project.
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