errors

Simple abstraction to handle custom errors in your codebase.

Installation

$npm install segmentio/errors
$component install segmentio/errors

Example

var RandomError = require('./random-error');
var errors = require('errors')();


/**
 * Add `Random` error to our known errors map.
 */

errors.add('Random', RandomError);


/**
 * Wrap any errors the map recognizes after getting from Mongo.
 */

function get (id, callback) {
  mongo.findById(id, function (err, res) {
    callback(errors.wrap(err), res);
  });
}

// random-error.js

var inherit = require('util').inherits;


/**
 * Random Error.
 */

function RandomError (err) {
  Error.call(this);
  Error.captureStackTrace(this, arguments.callee);
}

inherit(RandomError, Error);


/**
 * Check if `err` is a `RandomError`.
 */

RandomError.is = function (err) {
  return err && err.code == 1042;
};

API

errors()

Initialize a new error map.

.Errors

The map of error constructors, so you can expose it so external APIs can do things like check instanceof.

#add(name, Constructor)

Add a new error Constructor to the map with name. The Constructor must have a function to check whether the error is its type exposed as .is.

#match(error)

Check with the error matches any of the rules of the custom constructors.

#wrap(error)

Wrap an error in its appropriate custom constructor.