prepper/test/express/app.tests.js

Prepper is an event based api for pre-processing log events before routing them to your logging framework of choice

var request = require('request')
var app = require('./app')
var Repo = require('../..').handlers.Repo
var assert = require('chai').assert
var async = require('async')

describe('Example Express Application', function() {

    this.slow(2000)

    var repo = new Repo()

    before(function(cb) {
        app.start(repo.handle, cb)
    })

    afterEach(function() {
        repo.clear()
    })

    after(function(cb) {
        app.stop(cb)
    })

    it('should emit route specific log events', function(done) {
        request.get('http://localhost:3000/hello-world', function(err, res, body) {
            if (err) return done(err)
            if (res.statusCode !== 200) return done(new Error('Status: ' + res.statusCode))

            var debugEvents = repo.findBy('level', 'debug')
            assert.equal(debugEvents.length, 1)
            assert.equal(debugEvents[0].request.url, '/hello-world')

            var infoEvents = repo.findBy('level', 'info')
            assert.equal(infoEvents.length, 2)
            assert.equal(infoEvents[1].request.url, '/hello-world')
            assert.equal(infoEvents[1].response.statusCode, 200)
            done()
        })
    })

    it('should emit errors', function(done) {
        request.get('http://localhost:3000/oh-noes', function(err, res, body) {
            if (err) return done(err)
            if (res.statusCode !== 500) return done(new Error('Status: ' + res.statusCode))
            var errorEvents = repo.findBy('level', 'error')

            assert.equal(errorEvents.length, 2)
            assert.equal(errorEvents[0].request.url, '/oh-noes')
            assert.equal(errorEvents[0].error.message, 'Oh Noes')

            assert.equal(errorEvents[1].request.url, '/oh-noes')
            assert.equal(errorEvents[1].response.statusCode, 500)
            done()
        })
    })

    it('should not be more than 1% slower', process.env.SKIP_PERF_TEST ? undefined : function(done) {

        this.timeout(200000)
        this.slow(100000)

        async.parallel({
            withLogging: benchmark.bind(null, 'http://localhost:3000/hello-world'),
            withoutLogging: benchmark.bind(null, 'http://localhost:3000/hello-world-no-logging')
        }, function(err, results) {
            assert.ifError(err)
            assert.ok(((results.withLogging - results.withoutLogging) / results.withoutLogging) <= 1)
            done()
        })

        function benchmark(url, cb) {
            var before = Date.now()
            async.timesLimit(1000, 5, function(n, cb) {
                request.get(url, function(err, res, body) {
                    if (err) return done(err)
                    if (res.statusCode !== 200) return done(new Error('Status: ' + res.statusCode))
                    cb()
                })
            }, function(err) {
                cb(err, Date.now() - before)
            })
        }
    })
})