What Is Continuous Integration (CI)?
Continuous Integration Definition
Continuous integration refers to automating the code changes that come from several contributors into a singular software channel. In this DevOps practice, developers merge the changes to the code into a single repository. Once they do that, developers then run the automated builds and tests.
Continuous integration is related to software development. Continuous Integration (CI) is a practice in software development where multiple programmers integrate the code into a common mainline repository daily.
You can access the main code from this repository for automated builds and testing.
Continuous integration comes under the software release practice’s build or integration stage.
It includes the automation component and the cultural component. The automation component has a building service or a CI, whereas the cultural component teaches how to integrate frequently.
History of Continuous Integration
In the year 1994, Grady Booch coined the term Continuous Integration.
Kent Beck and Ron Jeffries put the concept of continuous integration into practice when working on Chrysler Comprehensive Compensation System Project.
Here they also invented the concept of extreme programming.
But going back to the times when the continuous integration wasn’t there, merging and testing codes was a challenging, expensive, and time-consuming task.
What Are the Benefits of Continuous Integration?
Continuous integration makes the software development process smooth.
All this helps in collaborating with different programmers who design various features in the software. Integrating the individual codes into the central repository provides transparency to the process.
It is beneficial in agile methodologies.
Why Do We Use Continuous Integration?
Below we will discuss seven reasons why you need to use Continuous Integration:
- With continuous integration, you can run your tests in the real world
- The continuous integration server can check your code for test coverage
- If all your tests within a particular branch are green, the CI server will automatically deploy the code to production.
- Continuous integration servers can trigger your build and compilation processes.
- Continuous integration has the feature of the parallel build. With the help of parallel build support, you can split your tests and build processes into varying machines. This process will be faster than the manual one.
- Your continuous integration and version control server can communicate with each other. These two servers will let you know when a merge request is good to go ahead.
- With CI, you can reduce the integration risk.
- You can have good code quality and less time to deploy
What Are Examples of Continuous Integration?
If you want to find examples of continuous integration, then visit the GitHub README page and search for colorful badges on top.
A common example of continuous integration is ReactJS.
Facebook’s ReactJS framework has a visible and robust continuous integration and delivery pipeline.
Visit their GitHub page, and you will get to know the type of automated process they use to run their codebase.
By clicking on the build option, you will also notice every step of the continuous integration processes and the pipeline.
Steps To Get Started With Continuous Integration
Let’s understand the five steps that will guide you to start with continuous integration.
- Prioritize writing tests for the key parts of your codebase
- You must get the continuous integration service which will help you automatically run tests on every push you give to the main repository
- Remind your team to integrate changes regularly
- Once you notice the broken build, fix it there and then
- For every new story that you implement, write tests
When you start with continuous integration, you need to slow down your releases.
For this purpose, you will also have to buy in from your product owners to avoid the pressure of shipping features without testing.
It is often recommended to start small with the simple tests and then implement complex tests.
Continuous Integration and Continuous Delivery
Continuous integration and continuous delivery are increasingly popular in many organizations because they help teams deliver software faster, more reliably, and higher quality.
Continuous integration is a practice where developers integrate their code into a shared repository multiple times a day.
Continuous delivery is a practice where developers deploy new features to production on each commit to the shared repository.
Continuous integration helps to ensure that developers can quickly identify and fix bugs in their code before teams deploy them to production.
It also helps them ensure their code works as expected across different environments, even when they have not yet completed the deployment process.
The continuous integration process consists of 3 main phases: Build, Test, and Deployment.
You can also use continuous integration in DevOps, which is an approach to managing software delivery by integrating all developers with operations teams.
It helps to reduce the time for release and maintain a high-quality product with less risk.
Continuous delivery is a practice that allows developers to work on multiple features at once, thereby increasing productivity and decreasing risk.
It also helps them deliver their product faster.
To keep track of your product’s progress, use the product roadmap software.
Continuous delivery releases software in short cycles, usually every day or every few hours.
Continuous delivery has three main benefits:
1. It allows teams to release software faster and more frequently.
2. It reduces the risk of releasing software with defects because developers can see what their changes have done immediately after making them.
3. It allows for rapid feedback from users who can provide input on what needs to be changed before it becomes a problem for other users.
The primary purpose is to make the process transparent and provide rapid feedback to access the main code and tweak any bug in the code quickly.
Some common CI tools are Jenkins, TeamCity, Bamboo, Buddy, GitLabCI, and CircleCI.