CI/CD для JS розробників. Частина друга – практика

Author: Inna Ivashchuk, Senior Software Engineer, Engineering, Consultant, GlobalLogic Ukraine

We continue to understand SI/CD to improve the lives of developers. The first part about the theoretical overview of the concept can be read at the link .

In this part, we’ll take a look at the main popular CI/CD tools you can use in development, try to quickly configure (and of course run) Travis CI, and take a look at GitHub Actions.

First, let’s recall the main practices that were analyzed last time and analyze the advantages of using each of them.

Advantages of using CI/CD practices

• Write automated tests.
• A server or service that will monitor the main repository and will run auto tests for each commit, which in turn will help us see the status and validity of the code.
• Merge the code as often as possible, at least once a day.

What will we get?

• The ability to catch most bugs, as tests that test core functionality inform developers that something has gone wrong.
• Speeding up the release.
• Much less switching between tasks for the developer.
• The ability to run a large number of tests on the server, which will work in just a few minutes.

In order to start using CD practice, you need:

• High code coverage by tests.
• Deployment should be automatic.
• Using additional flags that will allow us to hide unfinished functionality (for example, Launch Darkly).

What will we get?

• Web application deployment will become much easier.
• The ability to make a release much more often.

In order to start using the CD (continuous deployment) practice, you need:

• Different types of automated tests (integration, performance, acceptance, etc.) , written not only by developers, but also by QA .
• Documentation to keep up to date.
• Additional flags to help hide unfinished parts that are currently under development.

What will it give us?

• Fully automated release.
• There is no need to do a code freeze, due to the fact that the release is being prepared for a long time.
• No risks, because everything is thought out, configured and configured.
• Satisfied users who see improvements every week or even every day.

Easy start with Travis CI

And now it’s time to try one of the tools, namely Travis CI . In order to get started, we need:

• Go to travic-ci.com and log in using your GitHub account
• Confirm authorization at travis-ci.com , after which you will be redirected to GitHub.
• Go through a few simple steps and choose the repository to which we want to add Travis tracking.
• Add the travis.yml file to the selected repository, in which we will write literally a few lines and thus start the CI operation.

And now to the code!

• Example one .
• Example two. 

GitHub Actions: Why you should pay attention to them

GitHub Actions are definitely worth your attention because they:

• Built in GitHub, so integration is extremely fast
• Allow multi-container testing . GitHub has many different templates for all types of Continuous Integration
• Allows you to create your own actions and publish them on GitHub Marketplace
• Absolutely free for open source repositories

Key concepts of GitHub Actions:

• Actions are the smallest particles of the described behavior.
• Events that we can bind to, such as push, pull request, and perform certain tasks
• Runners
• Job
• Steps
• Workflow is directly our file, which describes step-by-step steps that contain actions, job and steps.

Here’s what it takes to connect GitHub Actions to a repository: a short video tutorial. 

Conclusions

Returning to the title of the article, it’s time to answer the question: CI/CD for JS – is it necessary or not?

Of course, yes! This is really a very hot topic, about which you should learn more, and most importantly, try to apply it to the project, at least conduct an experiment on your own repository.

We wish you success, and if you want more useful materials, visit our JS Community !