This document discusses testing Node.js applications. It covers the theory behind testing, different types of testing like unit and integration testing, and tools for testing Node.js like Mocha and Chai. It also discusses test-driven development (TDD), behavior-driven development (BDD), using clusters to take advantage of multiple cores, and benchmarking tests using Siege.

1. Testing Node.js
Theory

2. Why Testing?
●Verification: more confidence in the absence
of bugs
●Better code
●Changes can be made without risk of breaking
existing features

3. Types of testing
1.Unit Testing
Tests individual units: e.g.: compare password
part of a login service
2.Integration Testing
Tests a complete service or end-end feature:
e.g.: complete login service

4. Unit Tests vs. Integration Tests
Unit Tests Integration Tests
Number of tests required for
n components with m paths
each: m*n
Number of tests required for n
components with m paths each: m^n??
(to be checked)
Fast Slow
More important than
integration tests
Still important to test end-end functionality

5. Agile and Testing
●One of the core parts of agile methodology is
TDD
●To reap the benefits of agile, TDD should be
followed

6. TDD vs. BDD
●TDD (Test driven development) is an approach
that advocates writing unit tests for all
functionality
●BDD (Behavior driven development) can be
seen as a form of TDD that uses product-owner
/ backlog friendly language in tests

7. Testing Node.js
Application

8. Testing tools
Testing framework Mocha
BDD library Chai (expect & should)
Mocking framework Sinon.js
Proxyquire
Code organization JavaScript classes

9. Why Multi-core?
●Decrease in latency
●Test using node siege benchmarking
var siege = require('siege');
// run cpu bound service benchmark
siege()
.on(3000)
.for(1000).times
.concurrent(100)
.get('/')
.attack();

10. Cluster Semantics
●Very simple to use
●Multi-core benefits with only a few lines of
code
●Code divided into two sections:
○One for master process
○One for worker processes
●Various events are available to communicate
between processes

11. Thank you