With the help of this tutorial, you can learn how to create a continuous integration workflow for your Node JS REST API by using GitHub Actions as well as how to report test coverage with Coveralls.
When contributing to projects on version control platforms like GitHub and Bitbucket, the convention is that there is the main branch containing the functional codebase. Then, there are other branches in which several developers can work on copies of the main to either add a new feature, fix a bug, and so on. It makes a lot of sense because it becomes easier to monitor the kind of effect the incoming changes will have on the existing code. If there is any error, it can easily be traced and fixed before integrating the changes into the main branch. It can be time-consuming to go through every single line of code manually looking for errors or bugs — even for a small project. That is where continuous integration comes in.
What Is Continuous Integration (CI)?
“Continuous integration (CI) is the practice of automating the integration of code changes from multiple contributors into a single software project.” — Atlassian.com
The general idea behind continuous integration (CI) is to ensure changes made to the project do not “break the build,” that is, ruin the existing code base. Implementing continuous integration in your project, depending on how you set up your workflow, would create a build whenever anyone makes changes to the repository.
So, What Is A Build?
A build — in this context — is the compilation of source code into an executable format. If it is successful, it means the incoming changes will not negatively impact the codebase, and they are good to go. However, if the build fails, the changes will have to be reevaluated. That is why it is advisable to make changes to a project by working on a copy of the project on a different branch before incorporating it into the main codebase. This way, if the build breaks, it would be easier to figure out where the error is coming from, and it also does not affect your main source code.
“The earlier you catch defects, the cheaper they are to fix.” — David Farley, Continuous Delivery: Reliable Software Releases through Build, Test, and Deployment Automation
There are several tools available to help with creating continuous integration for your project. These include Jenkins, TravisCI, CircleCI, GitLab CI, GitHub Actions, etc. For this tutorial, I will be making use of GitHub Actions.
GitHub Actions For Continuous Integration
CI Actions is a fairly new feature on GitHub and enables the creation of workflows that automatically run your project’s build and tests. A workflow contains one or more jobs that can be activated when an event occurs. This event could be a push to any of the branches on the repo or the creation of a pull request. I will explain these terms in detail as we proceed.
Let’s Get Started!
Prerequisites
This is a tutorial for beginners so I will mostly talk about GitHub Actions CI on a surface level. Readers should already be familiar with creating a Node JS REST API using the PostgreSQL database, Sequelize ORM, and writing tests with Mocha and Chai.
You should also have the following installed on your machine:
- NodeJS,
- PostgreSQL,
- NPM,
- VSCode (or any editor and terminal of your choice).
I will make use of a REST API I already created called countries-info-api. It’s a simple api with no role-based authorizations (as at the time of writing this tutorial). This means anyone can add, delete, and/or update a country’s details. Each country will have an id (auto-generated UUID), name, capital, and population. To achieve this, I made use of Node js, express js framework, and Postgresql for the database.
I will briefly explain how I set up the server, database before I begin with writing the tests for test coverage and the workflow file for continuous integration.
You can clone the countries-info-api repo to follow through or create your own API.
Technology used: Node Js, NPM (a package manager for Javascript), Postgresql database, sequelize ORM, Babel.
#github #node #api #testing #developer
