How To Create New Jenkins Pipeline

Basics of Jenkins Pipelines

A pipeline is a series of steps that can be automated to achieve a desired result. It is written using a combination of the Groovy programming language and Jenkins’ specific Domain Specific Language (DSL).

The syntax and structure start with a top-level node, which is the section at the top of the script that controls the flow of the entire pipeline. This is followed by one or more stages which contain the actual tasks and steps to be executed. Each stage can be divided into steps, which can be implemented in a number of different ways, such as running a command, copying a file, or running a script. Additionally, each step may include multiple related steps, such as setting or cleaning up environment variables.

Jenkins offers two types of pipelines: Scripted and Declarative. Scripted pipelines are written entirely in the Groovy programming language and offer a more granular level of control and flexibility. Declarative pipelines provide a simpler syntax that is easier to read and maintain but has less flexibility and control.

Setting up Jenkins for Pipeline Creation

Step 1: Download Jenkins from its official website and install it on your system. Jenkins is available for both Windows and Linux/Unix-based systems.

Step 2: After the installation is complete, launch Jenkins. Configure settings and enable security by setting up an admin user.

Step 3: Install the necessary plugins and tools for pipeline creation. These include the Pipeline plugin which allows you to create pipelines of automated tasks, Git/GitHub plugins for version control, the NodeJS plugin for builds, the Ansible plugin to manage and deploy applications, the Email extension plugin to trigger emails based on build success/failure, and any other plugins needed for specific tasks.

Step 4: Now you can create jobs and configure them with the necessary parameters. Additionally, you will define a pipeline with the parameters necessary for a successful run. These parameters may include the source control repo, test results, deployment settings, etc.

Step 5: Test the pipeline once it is configured and all plugins and tools are in place.

Step 6: Enjoy the power of Jenkins for automating tasks and streamlining the development workflow.

Creating Your First Jenkins Pipeline

Step 1: Create a Basic Jenkins Pipeline:

• Log in to Jenkins and select “New Item” from the sidebar.

• Enter a name for the pipeline and select “Pipeline” from the list of Jenkins job types.

• Scroll down to the Pipeline section and select “Pipeline script from SCM” from the Definition drop-down.

• Select the version control system that you’re using to store your Jenkinsfile (e.g., Git, Subversion, etc.).

• Enter the repository URL where your Jenkinsfile is located and any credentials or keys needed to access the repository.

• Under Pipeline, select the Script Path, which is the location of your Jenkinsfile in the repository.

• Click Save to complete the process.

Step 2: Define the Stages:

• open up your Jenkinsfile and add a script block.

• Use the stages command to create the stages of your pipeline.

• The stages object takes a sequence of stage instructions that are executed sequentially.

Example: stages {
stage ('Build') {
steps {
// your build steps
}
}
stage ('Test') {
steps {
// your test steps
}
}
stage ('Deploy') {
steps {
// your deploy steps
}
}
}

Step 3: Define the Steps

• Inside each stage, you can define the steps that should be executed during that stage.

• Most steps require you to specify a ‘step’ directive followed by a command, which usually maps to a shell, batch, or PowerShell script.

• You can further customize the steps by adding additional options.

Example: steps {
// Shell script
step 'Example script':
sh "echo 'Hello World!'"
// PowerShell script
step 'Another script':
powershell (script: 'echo "Goodbye World!"')
}

Step 4: Post-build Actions

• Post-build actions are steps that should be executed after applying the preceding steps of the pipeline.

• Post-build actions are usually executed if all steps of the pipeline are successful.

• Common post-build action situations include notification emails, cleaning up a workspace, archiving artifacts, and triggering other Jenkins jobs.

Example: post {
always {
echo 'This will run regardless of the outcome of the build.'
}
success {
sendNotification 'deploy@example.
}

}