content.md

Continuous Integration & Continuous Delivery (CI/CD)

Simple deployment

What is it?

Continuous Integration (CI) - a practice in which members of a team integrate their work frequently.

Continuous Delivery (CD) - a discipline where software is built in a manner that allows for deploying to customers at any time.

Continuous Deployment (CD) - this extends Continuous Delivery by automating the deployment process so that code is automatically deployed to production after it passes automated testing.

Benefits

• More time for innovation
• Better retention rates
• More revenue
• Business efficiency

CI/CD Fundamentals

• A single source repository
  Source code management (SCM) that houses all necessary files and scripts to create builds.
• Automated builds
  Scripts should include everything you need to build from a single command.
• Builds should be self-testing
  Testing scripts should ensure that the failure of a test should result in a failed build.
• Frequent iterations
  Multiple commits to the repository mean there are fewer places for conflicts to hide.
• Stable testing environments
  Code should be tested in a cloned version of the production environment.
• Maximum visibility
  Every developer should be able to access the latest executables and see any changes made to the repository.
• Automated deployments
  Code should be able to deploy into multiple environments easily.

What is the CI/CD Pipeline?

CI/CD pipeline - an automated sequence of events that is initiated after you update the code.

Takes care of the work (that you would otherwise need to perform manually):

• previewing a in-development site
• testing a new code
• deploying it to a production server

CI/CD pipeline

CI/CD tools

• Travis CI
• GitLab CI
• Jenkins
• ...

Deliver to Registries

We can deliver new releases of software to registries.

Registry - is a software-package hosting service, that allows you to host your packages and code in one place.

Registry types:

• public ()
• private

Example public package registries

• NPM for JavaScript (NodeJS)
• MVN Repository for Java
• Python Package Index for Python

Examples of installing packages from a registry for using them in a project:

# For NodeJS
npm install PACKAGE_NAME

# For Java
mvn install PACKAGE_NAME

# For Python
pip install PACKAGE_NAME
pip3 install PACKAGE_NAME

Example public Image registry

• Docker Hub

Example box registry for virtual machines

• Vagrant Cloud