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0.10.1 • Public • Published


Build Status plugin for Node

Getting Started

Install the module with: npm install raygun

var raygun = require('raygun');
var raygunClient = new raygun.Client().init({ apiKey: 'your API key' });
// For express, at the end of the middleware definitions, just above app.listen:

Expressjs 4.0 and above

The Express documentation says Though not strictly required, by convention you define error-handling middleware last, after other app.use() calls, but that is incorrect. If the app.use(raygunClient.expressHandler); call is not immediately before the app.listen call, then errors will not be handled by Raygun.

Note that the Express middleware handler will pick up and transmit any err objects that reach it. If the app code itself chooses to handle states that result in 4xx/5xx status codes, these will not result in an error payload sent to Raygun.



The callback should be a node-style callback: function(err, response) { /*...*/ }. Note: If the callback only takes one parameter (function(response){ /*...*/ }) it will only be called when the transmission is successful. This is included for backwards compatibility; the Node-style callback should be preferred.

Sending custom data

You can pass custom data in on the Send() function, as the second parameter. For instance (based off the call in test/raygun_test.js):

client.send(new Error(), { 'mykey': 'beta' }, function (response){ });

Sending custom data with Expressjs

If you're using the raygunClient.expressHandler, you can send custom data along by setting raygunClient.expressCustomData to a function. The function will get two parameters, the error being thrown, and the request object.

var raygunClient = new raygun.Client().init({apiKey: "yourkey"});
raygunClient.expressCustomData = function (err, req) {
  return { 'level': err.level };


client.send(new Error(), {}, function (response){ });

The argument to the 3rd argument callback is the response from the Raygun API - there's nothing in the body, it's just a status code response. If everything went ok, you'll get a 202 response code. Otherwise we throw 401 for incorrect API keys, 403 if you're over your plan limits, or anything in the 500+ range for internal errors. We use the nodejs http/https library to make the POST to Raygun, you can see more documentation about that callback here:

Sending request data

You can send the request data in the Send() function, as the fourth parameter. For example:

client.send(new Error(), {}, function () {}, request);

If you want to filter any of the request data then you can pass in an array of keys to filter when you init the client. For example:

var raygun = require('raygun');
var raygunClient = new raygun.Client().init({ apiKey: 'your API key', filters: ['password', 'creditcard'] });


You can add tags to your error in the Send() function, as the fifth parameter. For example:

client.send(new Error(), {}, function () {}, {}, ['custom tag 1', 'important error']);

Tags can also be set globally using setTags

client.setTags(['Tag1', 'Tag2']);

Affected user tracking

New in 0.4: You can set raygunClient.user to a function that returns the user name or email address of the currently logged in user.

An example, using the Passport.js middleware:

var raygunClient = new raygun.Client().init({apiKey: "yourkey"});
raygunClient.user = function (req) {
  if (req.user) {
    return {
      identifier: req.user.username,
      fullName: req.user.fullName,
      firstName: req.user.firstName,
      uuid: req.user.deviceID


Param: req: the current request. Returns: The current user's identifier, or an object that describes the user.

This will be transmitted with each message sent, and a count of affected users will appear on the dashboard in the error group view. If you return an email address, and the user has associated a Gravatar with it, their picture will be also displayed.

If you return an object, it may have any of the following properties (only identifier is required):

identifier is the user identifier. This will be used to uniquely identify the user within Raygun. This is the only required parameter, but is only required if you are using user tracking.

isAnonymous is a bool indicating whether the user is anonymous or actually has a user account. Even if this is set to true, you should still give the user a unique identifier of some kind.

email is the user's email address.

fullName is the user's full name.

firstName is the user's first or preferred name.

uuid is the identifier of the device the app is running on. This could be used to correlate user accounts over multiple machines.

Any other properties will be discarded.

Note: setUser deprecated in 0.4

Release 0.3 previously had a setUser function that accepted a string or function to specify the user, however it did not accept arguments. This method is considered deprecated and will be removed in the 1.0 release, thus it is advised to update your code to set it with the new user function.

Version tracking

Call setVersion(string) on a RaygunClient to set the version of the calling application. This is expected to be of the format x.x.x.x, where x is a positive integer. The version will be visible in the dashboard.

Inner Errors

Starting from 0.10.0 support for inner errors was added. Provide option innerErrorFieldName to specify a field or a function on the error object to use for retrieval of an inner error. Inner errors will be retrieved recursively until there is no more errors. Option innerErrorFieldName defaults to cause which is used in VError, therefore VError is supported out of the box.

Changing the API endpoint

You can change the endpoint that error messages are sent to by specifying the host, port, and useSSL properties in the raygunClient.init() options hash. By default, host is, port is 443, and useSSL is true.


Call Raygun.onBeforeSend(), passing in a function which takes up to 5 parameters (see the example below). This callback function will be called immediately before the payload is sent. The first parameter it gets will be the payload that is about to be sent. Thus from your function you can inspect the payload and decide whether or not to send it.

You can also pass this in as an option to init() like this: raygunClient.init({ onBeforeSend: function(payload) { return payload; } });

From the supplied function, you should return either the payload (intact or mutated as per your needs), or false.

If your function returns a truthy object, Raygun4Node will attempt to send it as supplied. Thus, you can mutate it as per your needs - preferably only the values if you wish to filter out data that is not taken care of by the filters. You can also of course return it as supplied.

If, after inspecting the payload, you wish to discard it and abort the send to Raygun, simply return false.

By example:

var myBeforeSend = function (payload, exception, customData, request, tags) {
  console.log(payload); // Modify the payload here if necessary
  return payload; // Return false here to abort the send


Offline caching

Raygun can cache errors thrown by your Node application when it's running in 'offline' mode. By default the offline cache is disabled. Raygun4Node doesn't detect network state change, that is up to the application using the library.

Raygun includes an on-disk cache provider out of the box, which required write permissions to the folder you wish to use. You cal also pass in your own cache storage.

Getting setup with the default offline provider

When creating your Raygun client you need to pass through a cache path

var raygunClient = new raygun.Client().init(
        apiKey: 'API-KEY',
        isOffline: false,
        offlineStorageOptions: {
          cachePath: 'raygunCache/',
          cacheLimit: 1000 // defaults to 100 errors if you don't set this
Changing online/offline state

The Raygun client allows you to set it's online state when your application is running.

To mark as offline


To mark as online;

When marking as online any cached errors will be forwarded to Raygun.

Custom cache provider

You're able to provide your own cache provider if you can't access to the disk. When creating your Raygun client, pass in the storage provider on the offlineStorage property


 var sqlStorageProvider = new SQLStorageProvider();

 var raygunClient = new raygun.Client().init(
            apiKey: 'API-KEY',
            isOffline: false,
            offlineStorage: sqlStorageProvider,
            offlineStorageOptions: {
                table: 'RaygunCache'

Required methods

  • init(offlineStorageOptions) - Called when Raygun is marked as offline. offlineStorageOptions is an object with properties specific to each offline provider
  • save(transportItem, callback) - Called when marked as offline
  • retrieve(callback) - Returns an array of cached item filenames/ids
  • send(callback) - Sends the backlog of errors to Raygun

See lib/raygun.offline.js for an example.

We recommend that you limit the number of errors that you are caching so that you don't swamp the clients internet connection sending errors.

Custom error grouping

You can provide your own grouping key if you wish. We only recommend this you're having issues with errors not being grouped properly.

When initializing Raygun, pass through a groupingKey function.

var raygunClient = new raygun.Client().init({
    apiKey: 'YOUR_KEY',
    groupingKey: function(message, exception, customData, request, tags) {
        return "CUSTOMKEY";

Custom error objects

By default Raygun4Node tries to convert unknown objects into a human readable string to help with grouping, this doesn't always make sense.

To disable it:

var raygunClient = new raygun.Client().init({
    apiKey: 'YOUR_KEY',
    useHumanStringForObject: false

If your custom error object inherits from Error as its parent prototype, this isn't necessary however and these will be sent correctly.

Report column numbers

By default Raygun4Node doesn't include column numbers in the stack trace. To include column numbers add the option reportColumnNumbers set to true to the configuration.

var raygunClient = new raygun.Client().init({
    apiKey: 'YOUR_KEY',
    reportColumnNumbers: true

Including column numbers can enable source mapping if you have minified or transpiled code in your stack traces.


View a screencast on creating an app with Node.js and Express.js, then hooking up the error handling and sending them at


In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using "npm test".

To get the functional sending tests passing, set a RAYGUN_APIKEY environment variable to a valid apikey, e.g export RAYGUN_APIKEY=your_apikey.

Release History

View the changelog here


Copyright (c) 2016 Raygun Limited

Licensed under the MIT license.




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