Node.js uses a non-blocking I/O model which is event-driven, hence making it efficient and lightweight. The ecosystem of Node.js, NPM, is the largest open source library ecosystem in the world.
- I/O means input/output. It can be anything that ranges from writing/reading local files to making of an HTTP request into an API.
- I/O consumes time, thus, blocks other functions.
Let us consider a scenario where a backend database is requested for the particulars of user 1 and user 2 and then let us print it on the console or a screen. This request takes time to respond, however, both the user data requests will be carried out individually and at the same time.
Why does Node.js testing matter?
For some of the obvious reasons, it is important to go through a Node JS Test. Without testing, bugs can sneak into the system where fixing and repairing can be difficult and costly. Automatic testing significantly increases the test coverage and also helps in long-term cost reduction.
Tools and frameworks
Here is a brief review of various popular tools with an overview of how these tools can be integrated collectively to form an inclusive Node JS Test environment.
Frameworks that can be used:
While there are various testing tools available and a few new ones that are still under development, the following list expresses the uses of these tools:
Mocha is a great framework for testing, allows the use of asynchronous and promises with Babel or TypeScript. It handles the test execution a user creates, catches the assertion errors (if any), and pretty-prints these into the console.
Chai is a proclamation library that lets a user use natural language construct while developing the tests. Chai is tremendously helpful as a lot of assertion libraries may be rather cryptic.
It is a small NPM module which allows a user to substitute a mock test without having any modification done to the production code. Just with the creation of a module or a mock function and then registering it with the mockery, Node.js injects these mocks wherever in the code a require statement may be used.
This is a continuous integration system which can hook into a user’s version control, e.g. git and then automatically executes mocha whenever a commit occurs. This concludes that the product was tested each time during the occurrence of changes.
- WebStorm IDE
The Passport.js framework is an endorsing middleware for Node.js. It gives a user a choice of more than three hundred ways of validating an application containing password and username model, login via Google, Facebook, Twitter etc., and other web services too. It is really easy to imply with any Exspress.js app.
This is a framework that enables an event based bi-directional communications in real-time. It does not matter what platform or which device is being used, it works superbly on anything.
The Socket.io package contains a real-time analysis with logs, charts, and counters. It is perfect for the applications used for chats and is loved by small start-ups and big companies like Zendesk, Trello, Microsoft, etc.
This is a promise library which will help a user to control his/her asynchronous code. It can be separated by a code in various files without a problem. This is a must-have framework if a user cares about the quality of code. A developer may also try the Q as an alternative to the BlueBird.js framework.
This is a process managing framework for Node.js apps. It is quite simple to use and also provides a lot of useful inbuilt features such as watch mode or load balancer.