In this tutorial, we will guide you on how to implement a Continuous Integration/Continuous Deployment (CI/CD) pipeline using GitHub Actions, and discuss other alternatives like Jenkins, GitLab, and CircleCI.
Continuous Integration (CI) and Continuous Delivery (CD) embody a culture, set of operating principles, and collection of practices that enable application development teams to deliver changes more reliably and efficiently. CI/CD is one of the best practices for devops teams to implement.
CI is a development practice that requires developers to integrate code into a shared repository several times a day. Each check-in is then verified by an automated build, allowing teams to detect problems early.
By integrating regularly, you can detect errors quickly, which leads to building better software more rapidly.
CD is a short cycle time that ensures the software can be reliably released at any time. CD builds on the foundation that CI laid and takes it a step further by deploying all code changes to a testing environment and/or a production environment after the build stage.
When CI/CD pipelines are implemented properly, they provide many benefits, such as improved code quality, faster feedback cycles, and a reduced risk of introducing new software.
Some of the key reasons you should consider implementing a CI/CD pipeline are:
GitHub Actions makes implementing a CI/CD pipeline as simple as ever. Here's a step by step guide:
To follow along this tutorial you will need:
Here is a simple example of a GitHub Actions workflow that sets up a Java environment, builds Java code, and runs tests with Gradle:
name: Java CI with Gradle
on:
push:
branches: [ master ]
jobs:
build:
runs-on: ubuntu-latest
steps:
- name: Checkout the code
uses: actions/checkout@v2
- name: Set up JDK 1.8
uses: actions/setup-java@v1
with:
java-version: 1.8
- name: Build with Gradle
run: ./gradlew build
This pipeline will be triggered each time there is push action on the master branch. It will set up a Ubuntu environment with JDK 1.8 installed, then run Gradle to build the job.
Maintain a Code Repository: This is an absolute must for all development teams.
Automate the Build: Make your build self-testing. Every time you push your code, you should have the code and any other resources you need, build, test, and ready to deploy.
Test in a Clone of the Production Environment: You should set your CI system to deploy and test your application in an environment that's a clone of your production environment.
Everyone can see the results of the CI: The results of the latest build should be easily accessible to anyone who needs them.
Automate Deployment: Automatically deploying the application to the environment after each build allows you to identify any issues with the deployment process early on.
Here are a few alternative tools:
Jenkins: Jenkins is an open-source automation tool written in Java with built-in CI/CD functionality. It also supports version control tools like Subversion, Git, Mercurial, and Maven.
GitLab CI/CD: GitLab CI/CD is a powerful tool built into GitLab that allows you to apply all the continuous methods (continuous integration, continuous delivery, and continuous deployment) to your software with no third-party application or integration needed.
CircleCI: CircleCI is a cloud-based system -- no dedicated server required. And setting up CircleCI for a new project is easy. CircleCI can be connected with GitHub or Bitbucket account, and supports multiple languages including: Java, Ruby/Rails, Python, Node.js, PHP, Haskell, and Scala.
1. What's the difference between Continuous Deployment and Continuous Delivery?
While both practices require building and testing with each commit, Continuous Deployment, unlike delivery, doesn't require human intervention and deploys every change directly to the production environment.
2. Do I need a separate tool for CI and CD?
This depends on each organization. Some organizations might find it necessary while others just use a single tool for both CI/CD.
3. How often should I run my CI/CD pipelines?
In an ideal scenario, every commit should trigger the CI/CD pipeline. The faster you get feedback, the sooner you can respond and continue working on your task.
4. What do I need to get started with CI/CD?
The main prerequisites for CI/CD are: version control system, automated build and test tools, and deployment tools. Also, cloud environment or a similar isolated environment similar to the production setting.