DEPARTMENT OF COMPUTING
DEPARTMENT OF COMPUTING

Introduction to CircleCI Orbs

📌 What are CircleCI Orbs?

CircleCI orbs are a vital component in modern Continuous Integration and Continuous Delivery (CI/CD) pipelines. These orbs are reusable configurations that allow you to define, package, and share various parts of your CI/CD process, such as jobs, commands, and executors. Think of them as building blocks that make your CI/CD pipeline setup modular and efficient.

Orbs aren’t limited to in-house use; you can publish and share them with the broader development community through the CircleCI Orb Registry, thereby promoting best practices and reducing the need to reinvent the wheel for common tasks.

CircleCI Orbs Documentation

📌 Why Use CircleCI Orbs?

  1. Consistency: Orbs ensure that your CI/CD pipelines are consistent across different projects. This reduces the risk of configuration errors and makes pipelines more reliable.

  2. Efficiency: Instead of writing complex configuration from scratch for every project, you can leverage pre-defined orbs, saving time and effort. This can lead to faster development cycles and quicker time-to-market.

  3. Community Collaboration: Orbs foster community collaboration. You can use existing orbs to integrate best practices into your projects, and you can also contribute by creating and sharing orbs that solve common development challenges.

Getting Started with Orbs - CircleCI Blog

Anatomy of a CircleCI Orb

📌 What’s inside an orb?

orb.yml: This YAML file defines the structure and components of an orb. It contains the orb’s name, version, and a description. The orb.yml file references jobs, commands, and executors.

Here’s an example of an orb.yml file for a hypothetical “my-orb”:

version: 2.1
orbs:
  my-orb: your/awesome-orb@1.0.0
jobs:
  - build:
      executor: my-orb/default-executor
      steps:
        - my-orb/awesome-step

Jobs: Jobs define individual steps within a pipeline. They encapsulate specific actions, such as building an application, running tests, or deploying to a server. You can think of jobs as modular building blocks that you assemble to construct a complete pipeline.

Commands: Commands define reusable shell commands. These are often used within jobs to encapsulate common actions that are performed multiple times in your pipeline. Commands simplify your pipeline configuration and make it more readable.

Executors: Executors specify the environment in which jobs are executed. They define the machine or Docker image where the job’s commands will run. Executors provide a consistent runtime environment for your jobs.

Creating an Orb - CircleCI Docs

Using Existing Orbs

📌 How to use orbs from the Orb Registry?

To use an existing orb from the CircleCI Orb Registry:

  1. Search: Begin by searching for orbs related to your project’s needs in the CircleCI Orb Registry.

  2. Import: Once you find a suitable orb, import it into your project’s .circleci/config.yml file. This is done by specifying the imported orb’s namespace and version. Importing an orb makes its jobs, commands, and executors available for use in your pipeline configuration.

Here’s an example of importing an existing orb for Docker image building:

version: 2.1
orbs:
  docker: circleci/docker@0.1.3
  1. Customization: After importing, you can customize the imported orb’s components to fit your specific requirements. This allows you to fine-tune the orb’s behavior to match your project’s unique needs.

Using existing orbs not only accelerates your pipeline setup but also encourages good practices and standards, as the orbs are typically maintained by experts or the open-source community.

Using Orbs - CircleCI Docs

Implementing Orbs in a CI/CD Pipeline

📌 Practical examples of using orbs

To implement orbs in a CI/CD pipeline, consider the following practical examples:

  1. Docker Image Building and Deployment: You can use an existing orb for Docker image building and deployment. This orb encapsulates the necessary steps to build Docker images, tag them, and deploy them to a container registry or server. By importing this orb, you can simplify and standardize the process.

Here’s an example of using the “docker” orb to build and push a Docker image:

version: 2.1
orbs:
  docker: circleci/docker@0.1.3

workflows:
  version: 2
  build-and-deploy:
    jobs:
      - docker/build-and-push:
          context: my-docker-hub-context
  1. Configuring Pipeline Jobs: You can create a job in your pipeline configuration that uses commands from an orb. For example, you might have a job that uses a specific orb’s command to run integration tests, making your pipeline configuration concise and modular.

Here’s an example of a job that uses a command from an orb to run integration tests:

version: 2.1
orbs:
  my-orb: your/awesome-orb@1.0.0

jobs:
  build-and-test:
    executor: my-orb/default-executor
    steps:
      - my-orb/run-integration-tests

By leveraging orbs, you streamline your pipeline configuration and can easily update it as needed, all while maintaining best practices.

Orb Authoring Tutorial - CircleCI Docs

Advanced Orb Features

📌 Going beyond the basics

Here’s an example of using a parameter in an orb to specify a custom database URL:

version: 2.1
orbs:
  my-orb: your/awesome-orb@1.0.0

jobs:
  test:
    executor: my-orb/default-executor
    steps:
      - my-orb/run-tests:
          db-url: custom-db-url

Here

’s an example of conditional execution in an orb:

version: 2.1
orbs:
  my-orb: your/awesome-orb@1.0.0

jobs:
  deploy:
    executor: my-orb/default-executor
    steps:
      - when:
          condition: << pipeline.parameters.deploy-flag == 'true' >>
          steps:
            - my-orb/deploy-app

Here’s an example of specifying a specific orb version in your configuration:

version: 2.1
orbs:
  my-orb: your/awesome-orb@1.0.0

Advanced features make orbs incredibly powerful and adaptable to a wide range of use cases.

Advanced Orb Concepts - CircleCI Docs

Best Practices and Tips

📌 Make the most out of orbs

Orb Best Practices - CircleCI Docs

Last Updated 11/01/2023