7 Essential Jenkins Pipeline Stages

In the world of DevOps, keeping things moving is the name of the game. You want builds, tests, and deployments to flow like a river, not get stuck in a swamp. That’s where Jenkins Pipelines come in, and the stages within them act like the locks that keep the water flowing smoothly. Are you ready to learn more about this process? Let’s get to it.

What are Jenkins Pipeline Stages?

Jenkins Pipeline stages are the blocks that make up your Continuous Integration and Continuous Delivery (CI/CD) pipeline. Each stage is a specific step in your software delivery process. It could be compiling code, running tests, or deploying to a server.

Think of a factory assembly line. Each station does a specific job, and the product goes from one station to the next. Jenkins Pipeline stages work much the same way. They break down your complex process into smaller parts that are easier to manage.

This approach lets you do the following:

• Visualize the process: See the flow of your pipeline.
• Find bottlenecks: Easily spot where things are slowing down.
• Speed up development: Make changes and get feedback quicker.

Now, let’s dive into the 7 essential stages.

1. Checkout Stage: Getting the Code

The first step of almost any Jenkins Pipeline is the checkout stage. This is where you get your code. You need to pull the code from a repository, like Git, before you can do anything else.

Here’s what this stage does:

• Connects to your repository: It uses the credentials you set up in Jenkins.
• Gets the code: It pulls the latest version of your code.
• Keeps it safe: It makes sure you are using the right branch, tag, or commit.

Think of it as getting the raw materials for a product. You can’t build anything without them. In this case, you need the most up to date code before anything else can happen.

Here’s what a simple checkout stage may look like:

stage('Checkout') {
    steps {
        git url: 'https://github.com/your-repo/your-project.git',
            branch: 'main'
    }
}

In this example, we’re telling Jenkins to:

• Use the git command.
• Get the code from the repository at the given url.
• Use the main branch.

You might need to change the url and branch values to match your own project.

2. Build Stage: Turning Code into an App

Once you have the code, you need to build it. The build stage is where the code is compiled, bundled, and made ready for the next steps.

Here are the common tasks you see in the build stage:

• Compiling code: Converting code into machine-readable language.
• Creating a package: Bundling the compiled code and other assets into a deliverable unit, such as a JAR file, WAR file, or Docker image.
• Managing dependencies: Making sure the code has everything it needs to work, such as libraries and tools.

This is like taking the raw materials and turning them into parts for your product. You’re taking the code and making something useful. The type of build process may vary on the programming languages you will need.

Here’s what a simple build stage might look like for a Java project using Maven:

stage('Build') {
    steps {
        sh 'mvn clean install'
    }
}

In this example, we’re telling Jenkins to:

• Use the sh command.
• Run the Maven command mvn clean install.

This command will:

• Clean the project.
• Compile the code.
• Run any tests.
• Create a JAR file.

You would change the sh command if you use different build tools, like Gradle, or if you are working with other programming languages.

3. Test Stage: Ensuring the Quality

You need to test the code to make sure it works as it should. The test stage is where you run various kinds of tests. You want to make sure your code is good.

Here are some common types of tests you might run in this stage:

• Unit tests: Checking individual parts of the code.
• Integration tests: Testing how different parts of the code work together.
• System tests: Testing the whole system.
• Performance tests: Making sure the code can handle heavy use.

This is like the quality check station at a factory. You want to find any problems before they go to market. This is done by testing every part, big and small.

Here’s what a simple test stage might look like:

stage('Test') {
    steps {
        sh 'mvn test'
    }
}

In this example, we’re telling Jenkins to:

• Use the sh command.
• Run the Maven command mvn test.

This will run all the tests you have written in your project. The test results will show in Jenkins, so you can see if they passed or failed.

Make sure you write clear and thorough tests. They will help you catch bugs early.

4. Package Stage: Preparing for Deployment

Once the tests pass, you are ready to package your application. This stage is where you create a deployable unit.

Here are some common tasks in the package stage:

• Creating deployable units: Bundling the application into a format that can be deployed, like a Docker image or a ZIP file.
• Adding version control: Giving the package a unique version number.
• Storing the artifact: Uploading the package to a repository so you can use it to deploy to other servers.

This is like preparing the finished product for shipping. It’s done to get it ready for delivery to the end user.

Here’s what a simple package stage using Docker might look like:

stage('Package') {
    steps {
        sh 'docker build -t your-image-name .'
        sh 'docker tag your-image-name your-docker-repo/your-image-name:latest'
        sh 'docker push your-docker-repo/your-image-name:latest'
    }
}

In this example, we’re telling Jenkins to:

• Use the sh command.
• Build a Docker image with the name your-image-name.
• Tag the Docker image with the correct name for your Docker repository.
• Push the tagged image to the repository.

You would need to change these commands to fit with your Docker settings and repository.

5. Deploy Stage: Getting the App to Users

Now, you need to move the packaged app to its final destination. The deploy stage is where you push your application to a server, a cloud platform, or any other environment where it will be available to users.

Here are some of the things this stage might include:

• Deploying to an environment: Putting the app into a testing, staging, or production environment.
• Managing infrastructure: Making sure the environment has what it needs for the app.
• Updating configurations: Setting up the app to run correctly in the environment.

This stage is like delivering the finished product to your customers. You get the application in front of the end users.

Here’s what a simple deploy stage using SSH to a remote server may look like:

stage('Deploy') {
    steps {
        sshPublisher(publishers: [sshPublisherDesc(configName: 'your-server', transfers: [sshTransfer(cleanRemote: false, excludes: '', flatten: false, makeEmptyDirs: false, noDefaultExcludes: false, remoteDirectory: '/path/to/deploy', sourceFiles: 'your-artifact.jar')])])
    }
}

In this example, we’re telling Jenkins to:

• Use the sshPublisher plugin to transfer the file.
• Use the configuration with the name your-server.
• Transfer the file your-artifact.jar to the /path/to/deploy directory on your remote server.

You would need to change the plugin, configName, remoteDirectory, and sourceFiles to match your own setup.

6. Smoke Test Stage: Quick Check After Deployment

After deployment, you want to do a quick check to make sure the application is running. The smoke test stage makes sure the main functions of the app work correctly.

Here’s what a smoke test might do:

• Basic tests: Check to make sure the application is running.
• Simple features: Check main features.
• Verifying connectivity: Check external services are working.

This is like a quick check of the lights in your house after you move in. You want to make sure that everything is running as expected.

Here’s what a simple smoke test might look like using a curl command:

stage('Smoke Test') {
    steps {
        sh 'curl -s http://your-app-url/health'
    }
}

In this example, we’re telling Jenkins to:

• Use the sh command.
• Make a curl request to the URL http://your-app-url/health.

If the curl request gets a 200 OK response, the test is successful. The details of the command may vary by the specific test requirements.

7. Notify Stage: Keeping Everyone in the Loop

The final stage is to send notifications. This helps you let everyone know what happened during the pipeline.

Here are some common uses for this stage:

• Send email notifications: Send emails to the team.
• Update communication platforms: Send messages to Slack or Microsoft Teams.
• Record results: Log the outcome of the pipeline for future checks.

This stage keeps everyone on the same page. It helps people know what’s going on and what the outcome of the automated pipeline has been.

Here’s a simple example of how to send an email notification:

stage('Notify') {
    steps {
        mail to: '[email protected]',
          subject: "Pipeline Status: ${currentBuild.result}",
          body: "Build ${currentBuild.number} finished with status ${currentBuild.result}. Check the logs for more details: ${env.BUILD_URL}"
    }
}

In this example, we are telling Jenkins to:

• Send an email using the mail command.
• Send the email to [email protected].
• Include the build number and status in the email.
• Add a link to the build logs.

You can customize the email address, subject, and content to fit your needs.

Why These Stages Are Important

Using these stages in your Jenkins Pipeline is a good way to build a solid CI/CD system. Here are some reasons why:

• Improved organization: By breaking your process into these smaller parts, you can organize complex systems into smaller tasks.
• Better control: Each stage lets you control every step of the process, making it easier to find errors and make improvements.
• Clear visibility: When you visualize each stage, you can see the flow of your pipeline, which makes it easier to understand and monitor.
• Faster development: Each automated stage speeds up the process of building, testing, and deploying, so teams can get faster feedback and deploy code more often.
• Better quality: By running thorough tests in the pipeline, you can find and fix bugs early, which leads to a higher quality of code and more reliable applications.

Customizing Your Pipeline

These 7 essential stages are a good starting point. But, every project is different, and you need to tailor your pipeline to fit the requirements of your project.

You can add more stages to address specific needs, such as security scans or database updates. You can also skip some stages if they’re not needed for your project. You have a great deal of flexibility to customize each stage as needed.

The key is to make sure your pipeline is simple, easy to understand, and optimized to help you build and deploy quality software.

Key Things to Consider

As you set up your Jenkins Pipeline and the stages, here are some key things to keep in mind.

Use Declarative Syntax

The declarative syntax helps you organize the different steps and make them readable. Use the pipeline { } block to define your pipeline, and the stages { } block to define the different stages. This format lets you easily find and understand different stages.

Use Environment Variables

Environment variables are a good way to manage values you need across different stages of your pipeline. They let you store sensitive information such as API keys or usernames. When you manage information like this, you can update credentials or values without having to edit the pipeline file every time you change it.

Handle Errors Well

Errors happen. When they do, you need to be prepared to manage them. Jenkins lets you set up error handlers that can trigger specific steps. You can also set up notifications. This helps your team be aware of issues and lets them act quickly.

Make Use of Plugins

Jenkins has many plugins that let you add new features to your pipeline. These plugins will help you integrate with different services. From testing tools to deployment platforms, Jenkins has a large ecosystem of tools that work right away. This lets you extend your pipeline and help it suit your needs.

Make It Scalable

As your project grows, your pipeline must be able to handle more work. Jenkins helps you do this with features like agent management. By using different agents, you can run stages across different machines to keep things quick.

Essential Jenkins Pipeline Stages: A Recap

Let’s go over all the 7 Jenkins Pipeline stages we went over, one more time:

1. Checkout: This is where the code is brought in from your repository.
2. Build: Code is turned into a useful package.
3. Test: Making sure the code works as expected.
4. Package: This is where the app is readied for deployment.
5. Deploy: Getting the app to the server where users can use it.
6. Smoke Test: A quick check after deployment to make sure it works.
7. Notify: Keeping everyone informed about the pipeline outcome.

Are Jenkins Pipeline Stages Worth the Effort?

Setting up a Jenkins Pipeline with these stages takes time and effort. But it’s a worthwhile investment. When you build a good CI/CD system, you get to do the following:

• Save time: Automate tasks to speed up the delivery process.
• Lower risk: Catch bugs early with frequent tests.
• Increase quality: Make a better product with every push.
• Boost confidence: Deploy changes with confidence thanks to strong automation.
• Better collaboration: When all the steps are clear, your team can work together more easily.

In short, Jenkins Pipelines and their stages are key for today’s software development teams. They provide the structure you need to streamline your software delivery process and deliver high-quality software at speed.

So, now you know the 7 essential Jenkins Pipeline stages. But, knowing how to set up these stages won’t magically give you a smooth pipeline. Like building a house, each of these stages must work in harmony. Without a strong foundation, your build process will fall apart. When you combine all the stages correctly, your software release process can flow like a river, not get stuck in a swamp.