Understanding Life Before DevOps
To appreciate the power of GitLab CI/CD pipelines and the DevOps method of software development, we must understand how software was built before tools like GitLab appeared. Although you won’t learn anything practical in this chapter, you’ll learn about the world that GitLab CI/CD pipelines grew out of and get a clear picture of what problems GitLab CI/CD pipelines solve. Having a grasp of these things will set you up to understand why GitLab CI/CD pipelines operate the way they do and will open your eyes to the amazing power that they bring to the software development life cycle. In short, the best way to understand how things are now is to understand how bad they used to be!
This chapter will introduce you to a fictional but realistic web app called Hats for Cats+, which sells – you guessed it – head coverings for felines. You’ll get a quick overview of what’s involved with turning Hats for Cats from an idea into a well-written, tested, and deployed web app. You’ll see how these tasks would have to be done in a world where GitLab CI/CD pipelines don’t exist so that the benefits of GitLab will be even more obvious when you learn about them in later chapters.
In this chapter, we’re going to cover the following main topics:
- Introducing the Hats for Cats web app
- Building and verifying code manually
- Security-testing code manually
- Packaging and deploying code manually
- Problems with manual software development life cycle practices
- Solving problems with DevOps
