1. Overview
Jenkins is a powerful tool for automating the software development lifecycle. It’s an open-source workhorse that powers countless CI/CD pipelines, as it helps teams build, test, and deploy code faster and more reliably.
However, Jenkins is like a Swiss Army knife — powerful, versatile, and with a bit of a learning curve. That’s why we need best practices. By following a few simple guidelines, we can unlock Jenkins’ full potential, streamline our workflow, and ensure a smooth CI/CD process.
In this tutorial, we’ll cover a range of Jenkins best practices that’ll help us make the most of the tool.
2. Automating Job Definition
With Jenkins, job definitions are the blueprints for our software builds. Automating these blueprints can save us significant time and effort. Let’s imagine Jenkins as our tireless assistant, automatically creating, updating, and even deleting jobs based on changes in our code repositories.
There are a few powerful options for automatic job management in Jenkins. Organization Folders stand out as a preferred choice, notably for teams using platforms like GitHub, GitLab, Bitbucket, or Gitea:
With organization folders, Jenkins effortlessly detects new repositories and sets up the necessary jobs. This keeps everything in sync without manual intervention.
Alternatively, a Multibranch Pipeline offers a streamlined solution for managing projects with numerous branches. It automatically generates pipeline jobs for each branch, simplifying the management process.
In addition, if we crave more control, we can define pipeline jobs manually. This enables us to tailor our build process to our specific needs.
3. Managing Jobs Effectively
Managing Jenkins jobs effectively is like keeping a tidy workshop — everything has its place, and we can easily find what we need when we need it. This not only makes our lives easier but also streamlines the development process for the entire team.
Let’s start by organizing our jobs logically. We can use folders and views to group related jobs together. This makes our Jenkins dashboard clean and easy to navigate.
However, effective job management goes beyond just organization. We can also use descriptive names and labels so everyone knows what each job does at a glance.
Additionally, we can leverage automation to our advantage. This involves setting up build triggers that automatically start jobs when changes are pushed to our code repository.
Lastly, let’s remember to declutter. We need to regularly review and remove old or unused jobs, just like tidying up our workspace at the end of the day.
4. Reporting Build Results
Let’s think of build reports as our Jenkins health checkup. They give us a detailed look under the hood, revealing insights into the quality and performance of our software. This enables us to spot potential problems early on and keep our builds in good shape.
Jenkins comes equipped with a toolkit of reports that cover different aspects of our build process. Compiler warnings, for example, can be like early warning signs for issues in our code.
Furthermore, static analysis reports identify potential bugs, security vulnerabilities, and even code that might be a bit risky. Code coverage reports tell us how much of our code is actually being tested to ensure we’re not missing any blind spots.
In addition, performance test reports help us fine-tune our application for speed and efficiency.
However, to make the most of these reports, we can use handy plugins like the Warnings Next Generation plugin:
It aggregates various reports and puts them in one easy-to-read dashboard. This way, we can spot trends, track progress, and identify areas that need attention.
5. Building on Agents
While the Jenkins controller orchestrates our CI/CD pipeline, it’s the agents that do the heavy lifting of actually building and testing our software. These worker nodes provide the compute resources required to execute our jobs, and using them wisely can significantly enhance our Jenkins setup.
One major advantage of building on agents is improved safety. By offloading build tasks to separate machines, we isolate our Jenkins controller from potential risks like crashes or resource exhaustion caused by demanding builds.
This separation ensures that our controller remains stable and available for managing our pipeline.
Additionally, building on agents offers scalability. As our projects grow and our build requirements increase, we can easily add more agents to distribute the workload. This enables us to handle a higher volume of builds simultaneously and keep the pipeline moving efficiently, even under heavy load.
6. Securing and Backing up Our Controller
The Jenkins controller is like the command center of our CI/CD operation. It orchestrates everything, from scheduling jobs to managing plugins. This makes it a prime target for attackers, so security is important.
Fortunately, Jenkins comes with built-in security features enabled by default. However, it’s crucial to stay vigilant. Regularly updating Jenkins and its plugins can help patch any vulnerabilities.
In addition, we can implement strong authentication mechanisms like strong passwords or integrate with our organization’s single sign-on system. We can also restrict access to sensitive areas of Jenkins and grant certain permissions only to those who need them.
Equally important is backing up our controller regularly. This is like an insurance policy for our CI/CD pipeline. Should disaster strike — a hardware failure, a cyberattack, or even an accidental deletion — having a recent backup can save the day.
However, backups are only useful if we test them regularly to ensure they’re restorable.
7. Avoiding Resource Collisions and Scheduling Overload
Let’s imagine our Jenkins pipeline is a busy highway, with multiple builds zooming along simultaneously. Sometimes, these builds need to share the same resources, like databases or network services. Just like on a real highway, if everyone tries to merge into the same lane at the same time, we get a traffic jam.
In Jenkins, this translates to resource collisions and scheduling overload, which can slow down our builds and even cause them to fail. Fortunately, there are strategies to keep the traffic flowing smoothly.
One approach is to stagger our job schedules. Instead of having all our builds start at once, we can use Jenkins’ built-in scheduling features or the H syntax in cron expressions to introduce some randomness. This way, builds are more likely to run at different times, reducing the demand for shared resources.
On the other hand, even with careful scheduling, conflicts can arise sometimes. That’s where plugins like Lockable Resources can be quite helpful. This plugin acts like a traffic light at an intersection, allowing only one build to access a critical resource at a time.
However, if we’re still experiencing congestion, the Throttle Concurrent Builds plugin can help:
It limits the number of builds running at once. This ensures that our resources aren’t overwhelmed and that our builds are completed smoothly.
8. Conclusion
In this article, we’ve taken a quick tour of some essential Jenkins best practices that can empower us to create more efficient and reliable CI/CD pipelines.
Therefore, by continuously refining our Jenkins setup and adopting these best practices, we can ensure our CI/CD pipelines remain powerful assets to our teams.