error-cat

error-cat

A friendly feline companion that helps you create errors, track them, and report them via rollbar.

Basic usage

var ErrorCat = require('error-cat');

// Create, Log, and Report Errors
var err = ErrorCat.create(404, 'Not Found');

// Log and Report Errors
ErrorCat.log(someError);

// Report Errors via Rollbar
ErrorCat.report(anotherError);

Using error-cat with express

Error cat was designed to be as easy as possible to use with express. Here is an example of how to do so:

var express = require('express');
var app = express()

// 1. Require error-cat
var ErrorCat = require('error-cat');

// 2. Log and report errors using the static responder method
app.use(ErrorCat.middleware);

Extending error-cat

Error cat was designed as a prototypal class, so you can easily extend it using pure javascript:

var util = require('util');
var ErrorCat = require('error-cat');

//
// 1. Define your own ErrorCat class
//
function MyErrorCat() {
  ErrorCat.apply(this, arguments);
}
util.inherits(MyErrorCat, ErrorCat);

MyErrorCat.prototype.respond = function (err, req, res) {
  // Custom middleware...
};

MyErrorCat.prototype.report = function (err, req, res) {
  // Perhaps you want to report errors to more than just rollbar?
};


//
// 2. Use an instance with an application
//
var express = require('express');
var app = express();
var error = new MyErrorCat();
app.use(error.respond);

API

The error-cat module exposes a single class named ErrorCat. Below is a complete listing of its methods.

ErrorCat.middleware(err, req, res, next)

An express middleware that can be used to handle error responses with error-cat (uses the method respond detailed in the next section).

Note, this static method is set as writable: false, and will throw an error if you attempt to assign it a different value. If you need to change the default behavior please see the Extending error-cat section above.

ErrorCat Methods

{ErrorCat} new ErrorCat()

Constructs a new ErrorCat instance and initializes Rollbar if it is available.

{boolean} canUseRollbar()

Determines whether or not ErrorCat can use Rollbar to report errors. This method will return true if, and only if, process.env.NODE_ENV !== 'test' and process.env.ROLLBAR_KEY is defined.

Note: Error cat uses the loadenv package to load the environment so feel free to use its conventions to define ROLLBAR_KEY.

{Boom~Error} create(code, message, data)

Creates and automatically logs a new boom via the ErrorCat.log method (see below). The parameters mirror Boom.create.

{void} log(err)

Logs the given error using auto-debug and reports it to rollbar via ErrorCat.report (see below).

{void} report(err)

Reports the given error via Rollbar. This method is automatically bypassed if ErrorCat.canUseRollbar() returns false (see above).

Contributing

If you wish to contribute to error-cat please adhere to the following rules:

1. Build and read the jsdoc - npm run doc
2. Keep test coverage at 100%
3. When building new components, please use the same OOP style as index.js
4. For PRs include a good title, and a brief yet informative description of what your PR does.

License

MIT