Continuous Integration vs. Continuous Delivery
Continuous integration (CI) is a software development practice in which small adjustments to the underlying code in an application are tested every time a team member makes changes. CI aims to speed up the release process by enabling teams to find and fix bugs earlier in the development cycle and encouraging stronger collaboration between developers– making it a crucial practice for agile teams.
Historically, developers worked separately on parts of an application and would later integrate their code with the rest of the team’s manually. Depending on the when the next build occurred, it could take days, or even weeks, to see if the new code would break anything. This isolated process often lead to developers duplicating their code creation efforts, developing with different coding strategies, and creating many hard to find and fix bugs. In a CI environment, developers merge their code changes in a shared repository several times a day so that it can be committed, tested, and validated continuously. Implementing CI speeds up the development process and ensures that bugs are caught earlier in the cycle.
Continuous delivery (CD) is the process of getting new builds into the hands of users as quickly as possible. It is the natural next step beyond CI and is an approach used to minimize the risks associated with releasing software and new features. Releasing software updates is notoriously painful and time-consuming. Continuous delivery reduces the risks and efforts associated with this process by ensuring that every change made to the underlying code of an application is releasable – meaning each update is smaller and can be delivered to users more frequently. By making releases less dramatic events that can be performed on-demand whenever new code is ready, teams can make their development process more efficient, less risky, and can get feedback from users quicker. If issues are found in production, they can be squashed quickly by simply rolling out the next update.
The CI/CD Pipeline
As more software development teams aim to meet the growing demand for faster release cycles and increased software quality, many are looking to implement a continuous development pipeline to streamline their process. Adopting CI/ CD practices enable teams to adapt their software on-demand to meet user feedback, market shifts, and any adjustments to the overarching business strategy (i.e., changes to the requirements).
While there is no definitive CI/CD pipeline structure, it is typically broken down into the following stages:
- Commit & Build: When developers are finished making changes to an application, they commit their code to a shared repository which will then integrate their snippet with the central code base. The piece of software, or the new feature, is then built from the extracted code and unit tested. CI plays an essential role in streamlining this process by automating each step after the code is written.
- Automated Testing: Once the new piece of software is developed, it needs to be built and then thoroughly tested to ensure it meets all the initial requirements. There are various testing methodologiesthat can be used to ensure an application looks and behaves as expected and covers everything from functional tests to performance tests. During this stage, it’s essential to test the entire system in environments that are similar to the production environment because the success of the software depends on it working in the environments your end users are accessing it on.
- Deployment: In the final stage, the built piece of software is rolled out into production. CD requires this process to be automated, which ensures a reliable delivery to users.
Manual Testing, Its Adverse Effects, & the Importance of Automation
The CI/CD pipeline requires development, test, and operations teams to work together to create a cohesive release process and the key is automation.
The problem is that manual testing isn’t dead. It is a pervasive process that is still used throughout the industry across every stage of the development cycle. While it does serve a distinct purpose and will always be needed for specific types of testing, such as exploratory testing, it can hinder an iterative delivery process. Time is of the essence in a continuous environment and manual testing can be painfully sluggish. The slower the feedback loops, the longer it will take to make adjustments and release software. Automation accelerates the build and deploy cycle by checking code and running tests continuously and providing feedback within minutes. This is why as much of the process as possible should be automated, from unit tests to system tests and even environment provisioning.
For example, if you don’t commit your code continuously, you’ll have longer periods between integrations, making it harder to find and fix bugs. Waiting days or even weeks between builds can easily derail a project before it even reaches the testing stage.
The testing stage can be broken down into multiple parts based on the objective of each of your test ‘suites,’ each of which is designed to ensure the software meets the original business requirements. Whether you’re testing the application’s functionality, security, or performance, each suite can and should be automated. With the right tool, you can run regression tests to re-test scenarios each time a change is made to ensure the application’s existing functionality hasn’t been broken. The right tool will also allow you to conduct parallel testing, which is the process of running multiple tests, or tests cases, simultaneously on different browsers or systems. Running tests concurrently improves test coverage and will cut down on testing times, which is key to optimizing an iterative test process.
An often-overlooked part of the entire cycle is how test environments are managed. Most teams are still spending hours, or days, manually building, upgrading, and tearing down test environments. A crucial piece to ensuring happy customers is making sure your software works in the environment they’re accessing it on, so it’s important to test in environments that mimic the production environment. Technology today is constantly changing, meaning new operating systems, browser versions, and resolutions are being introduced to consumers on a regular basis. If you’re still managing test environments manually, you’ll spend an exorbitant amount of time trying to keep up.
Automated environment provisioning allows teams to manage test environments with just a few clicks. The right automated testing tool will even provide the latest versions of browsers, systems, and resolution configurations – meaning QA teams can avoid having to spin up, maintain, or tear down environments altogether.
Everything in your software development cycle, from unit tests to system tests and even environment provisioning, should be automated. You’re only as fast as the slowest phase of your pipeline and one stage conducted manually will turn into a bottleneck for the entire operation.
Top 5 Benefits of an Automated Continuous Development Process
There are five aspects of a continuous development process you’ll benefit from by transitioning to the CI/CD pipeline:
- Faster Release Cycles: Speeding up the build and deploy cycle will allow you and your team to get new features into production quicker, meaning you can get your product into the hands of your consumers faster.
- Reduced Risk: The ultimate goal of a continuous delivery process is to make each release a less-dramatic and painless experience for both the QA teams and customers. By releasing new updates or features continuously, you reduce the risk of bugs ending up in production and can resolve any found deficiencies faster.
- Lower Costs: Adopting a continuous development model will lower your costs by eliminating many of the fixed costs associated with building and testing changes to the application. For example, automated environment provisioning will reduce the costs associated with maintaining your own test infrastructure. Parallel testing will cut down on the number of machines you need to run your tests on. By continuously committing your code, you’ll spend less time (and therefore money) on fixing bugs.
- Higher Quality Products: A major fear of implementing the CI/CD pipeline is foregoing quality for speed, but this isn’t the case. Continuous integration enables stronger collaboration between developers, meaning bugs are found and fixed faster earlier in the development process. Running automated regression and parallel tests will improve test coverage, ensuring your application is bug-free and works across a wider range of environments. Continuously delivering smaller updates to your software will make most changes (and bugs) undetectable to the end user, resulting in happier customers.
- Better Business Advantage: Moving to a continuous development model gives your team the flexibility to make alterations to your software on-the-go to meet new market trends and user needs. You’ll be able to meet rapidly changing demands and will turn your release process into a competitive advantage.
Integrating TestComplete Into Your CI/CD Model
The first step to ramping up a CI/CD pipeline is adopting the right tools. TestComplete, our comprehensive automated testing tool, allows you to create and run functional UI tests across desktop, mobile, and web applications. The tool supports a wide variety of test types required by a continuous delivery cycle including unit and regression testing.
TestComplete has built-in plugins and extensions with developer-friendly tools like Visual Studio and Jenkins, so you can easily share assets between your developers and testers. TestComplete also comes with out-of-the-box support for numerous source control systems such as Git and Mercurial, allowing you to commit and keep track of code changes without leaving the tool.
Add-ons, such as TestExecute or Environment Manager, will allow you to run tests in parallel and automatically provision your test environments in the cloud, cutting down on the number of machines and time needed to run tests. TestComplete’s many features and integrations will allow you to seamlessly integrate it into your development process and will enable you start building a continuous development pipeline – lowering your costs, reducing risks, and ensuring happier customers with higher quality products.