Introduction to Continuous Integration and Continuous Deployment

Before we implement CI/CD in the Cat.ly application, let’s go over the principles of CI/CD.

CI/CD is considered to be one of the best practices for software development as it ensures the rapid delivery of reliable, risk-free, high-quality code. It is broken down into these two concepts:

• Continuous Integration
  Continuous Integration (CI) is the development practice of integrating new or changed code into an existing code repository automatically. The configured CI system then verifies each integration by performing immediate automated builds and tests of the application every time the code is updated and saved.

• Continuous Deployment
  Continuous Deployment (CD) is the approach of automatically deploying the code that was built and tested by the CI system to a production system or a staging system. Continuous Deployment occurs after the Continuous Integration stage, and ensures that the updated code is always ready to be used.

Deployment Pipeline in CI/CD

The deployment pipeline in CI/CD dictates the logic and the steps involved in implementing CI/CD, from the initial testing stages to the final deployment of the code to production. A well-defined deployment pipeline is crucial to ensure the CI/CD approach is completely effective.

Once you configure the deployment pipeline for your application and define the workflow, you can enable complete automation in integrating and deploying your application code.

Purpose of CI/CD

CI/CD enables instant deployment and thorough testing of the code each time you update your application. Whenever you make changes to your code, no matter how minor, CI/CD enables immediate automated testing on the code to ensure that the change fits well with the existing codebase. This helps reduce risks and increase production speed in the software development process.

It is good practice to push the code to a staging environment, where you can perform integrated and unit tests in a production-like environment. If your code is especially reliant on external dependencies and services, CI/CD easily ensures the integrity of the code maintained for every minor update.