mrister

/**
 * An error logger backed by Loggly
 */

require('dotenv').config({silent: false});

var loggly = require('loggly');

var client = loggly.createClient({
  token: process.env.LOGGLY_TOKEN,

mrister

const VError = require('verror').VError;
const WError = require('verror').WError;

const errReqFail = new Error('Request failed');
const errReqStatus = new VError(errReqFail, 'Unexpected status code "%s"', '500');
const errReq = new WError(errReqStatus, 'Internal error');

console.error(errReq.message); //Internal error:
// get some real data for logging
console.info(errReq.toString()); //WError: Internal error; caused by VError: Unexpected status code "500": Request failed

mrister

const VError = require('verror');
const errReqFail = new Error('Request failed');
const errReqStatus = new VError(errReqFail, 'Unexpected status code "%s"', '500');
const errReqBase = new VError(errReqStatus, 'Internal error');

console.error(errReqBase); //VError: Internal error: Unexpected status code "500": Request failed
// unwind to check cause
console.info(errReqBase.cause().message); //Unexpected status code "500": Request failed

mrister

function * genThrow() {
    yield 'egg';
    throw new Error('I am out of eggs');
}

try {
    const eggy = genThrow();
    eggy.next();
    // second call invokes throw
    eggy.next();

mrister

function *genTestError() {
    while (true) {
        try {
            var val = yield null;
            console.log('value', val);
        } catch (e) {
            console.log('There was an error', e);
        }
    }
}

mrister

process.on('uncaughtException', (err) => {
    logger.log('whoops! There was an uncaught error', err);
    // do a graceful shutdown,
    // close the database connection etc.
    process.exit(1);
});

mrister

const EventEmitter = require('events');

class Emitter extends EventEmitter {}

const emitter = new Emitter();
const logger = console;

/**
 * Add Error listener
 */

mrister

process.on('unhandledRejection', function (reason, promise) {
    logger.error('Unhandled rejection', {reason: reason, promise: promise})
});

mrister

/**
 * A custom MyError class
 * @class
 */
class MyError extends Error {
    /**
     * Constructs the MyError class
     * @param {String} message an error message
     * @constructor
     */

mrister

/**
 * A custom MyError class
 * @class
 */
class MyError extends Error {
    /**
     * Constructs the MyError class
     * @param {String} message an error message
     * @constructor
     */