Over the years, we have published a lot of content on Zuul, the CI/CD tool, and related topics. This omnibus aims to bring you all of those valuable, informational content together so that you can access it all from a one-stop solution. Each section is linked to a detailed blog where you can find more information about the said topic. Here’s what you need to know about Zuul. Let’s start from the basics. 

What is CI/CD?

When it comes to developing and releasing software, application development teams know how complicated the process can be, primarily with the challenges of deployment infrastructures and projects that continue to grow in complexity. That’s where continuous integration, continuous delivery, and continuous deployment come in.

The practice of continuous integration involves developers consolidating changes as frequently as possible to the main branch. The validation of these changes is handled by developing a build that runs automated tests against itself.

Continuous delivery acts as an extension of continuous integration. This practice ensures that updates are made available to users in a manner that is time-sensitive and sustainable. Additionally, deployments can be made at the same time as the release cycle, and the testing has been automated.

With continuous deployment, any change made that successfully passes each production line stage will be released to users. This means that the only way a change won’t be deployed is through failing a test as there is also no human intervention. 

The CI/CD Pipeline

CI/CD pipeline is a tool that helps in automating software delivery processes. The pipeline is capable of building code, running tests (CI), and safely deploys a new version of the application (CD). In an efficient CI/CD pipeline, these processes are automated, the manual errors are fixed, there are feedback loops, and the steps are fully logged and accessible to the necessary personnel.

A good CI/CD pipeline that is fast, reliable, and precise can have a significant impact on the application production and usage timeline. Here are some of the many benefits of the pipeline:

  • Automated processes
  • Developers can focus on coding and monitoring
  • Easy product upgrades
  • Improved access to QA and stakeholders
  • Easy rollbacks of versions
  • Anytime inspection of processes
  • Faster feedback

The Need of Zuul as a CI/CD Tool

Zuul brings you an open-source, open-design tool for merging code, ensuring that no broken code is merged into the main branch. Zuul was first developed in 2012 for CI testing. Its purpose was to enable users and contributors from different institutions to collaborate efficiently and effectively in varied projects. The tool was designed so that developers have a tool to test serialized future states faster when executing serial testing.

Zuul has several key features that differentiate it from other CI/CD tools, but the one at the forefront of its development is project gating. Zuul’s automation ranges from simple commit checks to the entire release process; therefore, its services are applicable through the whole DevOps journey. 

Similar CICD Tools for DevOps

Over time, multiple CI/CD tools have been developed, some serving a certain aspect of DevOps and some focussing on the entire set of practices. Here is a look at few examples, other than Zuul.

Jenkins is an open-source CI/CD tool with about 1400 plugins. It is written in Java, and everything from source code management to platforms to building management and so much more is handled via the means of these third-party modules. Over these years, Jenkins has advanced into an adaptable software automation server while being quickly modifiable and extensible.

GitLab CI is a continuous integration tool built into GitLab, therefore requiring only a single conversation between planning and deployment. GitLab supports a multi-platform and multi-language layout. GitLab also supports parallel builds and splits builds over multiple machines for faster execution. 

Circle CI is a continuous integration tool with automated deployment, deploying builds to reach the market faster. As a part of the continuous integration process, it allows you to test each commit and run builds on a clean virtual machine or container. With Circle CI, you have the option to host in on the cloud or an on-premise server.

Travis CI is a hosted continuous integration tool used to build and test software projects. Travis CI Enterprise is the version of the tool for on-premise products, in case you are focussed on a more secure environment. 

Multi-Repository Dependencies with Zuul

Ensuring flexibility for developers is essential for an efficient CI/CD tool as it can give significant benefits. Zuul is one such tool that functions on a Git-driven philosophy and therefore reads most of its configurations from git repositories. Thus, making limitations a thing of the past through Zuul’s flexible configurations and multi-repository dependencies. Zuul has had an extensive integration with Gerrit, and its latest release, Version 3, supports a much broader range of use cases and development platforms. Some of the most notable being its integration with GitHub.

Having multi-repository dependencies comes with benefits for all Zuul users,

  1. Multiple repositories make it easy to give access to subsets of repositories on a “need to code” basis.
  2. Each repository can have its own process of being deployed, making continuous delivery and deployment easier.
  3. Developers take advantage of multiple development platforms to create Adhoc continuous integration tests for exactly what they are working on at the moment.
  4. Developers also have the ability to work across project boundaries.
  5. Cross community continuous integration testing is also supported via multi-repo.
  6. With the option of GitHub Enterprise, all repository data can be stored on your organization’s local network and integrated with your organization’s authentication system.

Microservices: Cross-Project Dependencies In Zuul

Microservices act as a constellation of apps, or a software ecosystem that works as a team to improve the workflow. Each aspect of the workflow functions through its individual application. Ultimately, this ecosystem makes things run more smoothly. This is a long journey from a one size fits all software that did everything.

Of course, with so many smaller apps, a change in code could have an impact on the entire system due to the dependencies between applications. A code that may work well for one application may cause another to crash. This is where Zuul comes in. Since all applications depend on each other, Zuul makes sure that merging broken code is a thing of the past.

One of the features of Zuul is that it allows users to set out specific dependencies across their projects. Through the use of a special footer, it causes a change to depend on another change in any repository known to Zuul. This means that your first change might depend on your second, but your second change may not necessarily depend on your first change. Thanks to cross-project dependencies in Zuul, microservices are able to run exactly as they should.

Managed Zuul from VEXXHOST

Our Managed Zuul offering is available not only to our public and private cloud customers but also to anyone who has their infrastructure supported by OpenStack, Openshift, Kubernetes, or AWS EC2. Our offering’s vast reach is due to Zuul’s support of multiple cloud infrastructure providers. 

VEXXHOST knows Zuul first hand as it has been tested on our cloud, all the while using it internally for continuous integration. VEXXHOST is excited to empower organizations to make the most of this helpful project gating tool. As an experienced cloud computing provider, we know the importance of bringing on new and beneficial features. Our clouds are based on OpenStack, making the environments free from licensing fees or vendor lock-ins. For many of our clients, private clouds are the preferred choice because of their highly scalable and secure nature.  

Speaking of private clouds, you can now run on a fully agile and customized cloud from VEXXHOST, with no licensing fees and smooth 2-week migration. In fact, we’re ready to put our money where our mouth is. We’re so confident in being able to save you at least 20% or more on your current cloud infrastructure expenditure that if proven wrong- we’ll give you $1,000 credit to our public cloud.   

Excited? Find out more