Note: GitHub-hosted runners are not currently supported on GitHub Enterprise Server. You can see more information about planned future support on the GitHub public roadmap.
Introduction
CircleCI and GitHub Actions both allow you to create workflows that automatically build, test, publish, release, and deploy code. CircleCI and GitHub Actions share some similarities in workflow configuration:
- Workflow configuration files are written in YAML and stored in the repository.
- Workflows include one or more jobs.
- Jobs include one or more steps or individual commands.
- Steps or tasks can be reused and shared with the community.
For more information, see "Understanding GitHub Actions."
Key differences
When migrating from CircleCI, consider the following differences:
- CircleCI’s automatic test parallelism automatically groups tests according to user-specified rules or historical timing information. This functionality is not built into GitHub Actions.
- Actions that execute in Docker containers are sensitive to permissions problems since containers have a different mapping of users. You can avoid many of these problems by not using the
USER
instruction in your Dockerfile. For more information about the Docker filesystem on GitHub Enterprise Server-hosted runners, see "Using GitHub-hosted runners."
Migrating workflows and jobs
CircleCI defines workflows
in the config.yml file, which allows you to configure more than one workflow. GitHub Enterprise Server requires one workflow file per workflow, and as a consequence, does not require you to declare workflows
. You'll need to create a new workflow file for each workflow configured in config.yml.
Both CircleCI and GitHub Actions configure jobs
in the configuration file using similar syntax. If you configure any dependencies between jobs using requires
in your CircleCI workflow, you can use the equivalent GitHub Actions needs
syntax. For more information, see "Workflow syntax for GitHub Actions."
Migrating orbs to actions
Both CircleCI and GitHub Actions provide a mechanism to reuse and share tasks in a workflow. CircleCI uses a concept called orbs, written in YAML, to provide tasks that people can reuse in a workflow. GitHub Actions has powerful and flexible reusable components called actions, which you build with either JavaScript files or Docker images. You can create actions by writing custom code that interacts with your repository in any way you'd like, including integrating with GitHub Enterprise Server's APIs and any publicly available third-party API. For example, an action can publish npm modules, send SMS alerts when urgent issues are created, or deploy production-ready code. For more information, see "Creating actions."
CircleCI can reuse pieces of workflows with YAML anchors and aliases. GitHub Actions supports the most common need for reusability using matrices. For more information about matrices, see "Using a matrix for your jobs."
Using Docker images
Both CircleCI and GitHub Actions support running steps inside of a Docker image.
CircleCI provides a set of pre-built images with common dependencies. These images have the USER
set to circleci
, which causes permissions to conflict with GitHub Actions.
We recommend that you move away from CircleCI's pre-built images when you migrate to GitHub Actions. In many cases, you can use actions to install the additional dependencies you need.
For more information about the Docker filesystem, see "Using GitHub-hosted runners."
For more information about the tools and packages available on GitHub-hosted runner images, see "Using GitHub-hosted runners".
Using variables and secrets
CircleCI and GitHub Actions support setting variables in the configuration file and creating secrets using the CircleCI or GitHub Enterprise Server UI.
For more information, see "Variables" and "Using secrets in GitHub Actions."
Caching
CircleCI and GitHub Actions provide a method to manually cache files in the configuration file.
Below is an example of the syntax for each system.
CircleCI syntax for caching
- restore_cache:
keys:
- v1-npm-deps-{{ checksum "package-lock.json" }}
- v1-npm-deps-
GitHub Actions syntax for caching
- name: Cache node modules
uses: actions/cache@v3
with:
path: ~/.npm
key: v1-npm-deps-${{ hashFiles('**/package-lock.json') }}
restore-keys: v1-npm-deps-
GitHub Actions does not have an equivalent of CircleCI’s Docker Layer Caching (or DLC).
Persisting data between jobs
Both CircleCI and GitHub Actions provide mechanisms to persist data between jobs.
Below is an example in CircleCI and GitHub Actions configuration syntax.
CircleCI syntax for persisting data between jobs
- persist_to_workspace:
root: workspace
paths:
- math-homework.txt
...
- attach_workspace:
at: /tmp/workspace
GitHub Actions syntax for persisting data between jobs
- name: Upload math result for job 1
uses: actions/upload-artifact@v3
with:
name: homework
path: math-homework.txt
...
- name: Download math result for job 1
uses: actions/download-artifact@v3
with:
name: homework
For more information, see "Storing workflow data as artifacts."
Using databases and service containers
Both systems enable you to include additional containers for databases, caching, or other dependencies.
In CircleCI, the first image listed in the config.yaml is the primary image used to run commands. GitHub Actions uses explicit sections: use container
for the primary container, and list additional containers in services
.
Below is an example in CircleCI and GitHub Actions configuration syntax.
CircleCI syntax for using databases and service containers
---
version: 2.1
jobs:
ruby-26:
docker:
- image: circleci/ruby:2.6.3-node-browsers-legacy
environment:
PGHOST: localhost
PGUSER: administrate
RAILS_ENV: test
- image: postgres:10.1-alpine
environment:
POSTGRES_USER: administrate
POSTGRES_DB: ruby26
POSTGRES_PASSWORD: ""
working_directory: ~/administrate
steps:
- checkout
# Bundle install dependencies
- run: bundle install --path vendor/bundle
# Wait for DB
- run: dockerize -wait tcp://localhost:5432 -timeout 1m
# Setup the environment
- run: cp .sample.env .env
# Setup the database
- run: bundle exec rake db:setup
# Run the tests
- run: bundle exec rake
workflows:
version: 2
build:
jobs:
- ruby-26
...
- attach_workspace:
at: /tmp/workspace
GitHub Actions syntax for using databases and service containers
name: Containers
on: [push]
jobs:
build:
runs-on: ubuntu-latest
container: circleci/ruby:2.6.3-node-browsers-legacy
env:
PGHOST: postgres
PGUSER: administrate
RAILS_ENV: test
services:
postgres:
image: postgres:10.1-alpine
env:
POSTGRES_USER: administrate
POSTGRES_DB: ruby25
POSTGRES_PASSWORD: ""
ports:
- 5432:5432
# Add a health check
options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 5
steps:
# This Docker file changes sets USER to circleci instead of using the default user, so we need to update file permissions for this image to work on GH Actions.
# See https://docs.github.com/actions/using-github-hosted-runners/about-github-hosted-runners#docker-container-filesystem
- name: Setup file system permissions
run: sudo chmod -R 777 $GITHUB_WORKSPACE /github /__w/_temp
- uses: actions/checkout@v4
- name: Install dependencies
run: bundle install --path vendor/bundle
- name: Setup environment configuration
run: cp .sample.env .env
- name: Setup database
run: bundle exec rake db:setup
- name: Run tests
run: bundle exec rake
For more information, see "About service containers."
Complete Example
Below is a real-world example. The left shows the actual CircleCI config.yml for the thoughtbot/administrator repository. The right shows the GitHub Actions equivalent.
Complete example for CircleCI
---
version: 2.1
commands:
shared_steps:
steps:
- checkout
# Restore Cached Dependencies
- restore_cache:
name: Restore bundle cache
key: administrate-{{ checksum "Gemfile.lock" }}
# Bundle install dependencies
- run: bundle install --path vendor/bundle
# Cache Dependencies
- save_cache:
name: Store bundle cache
key: administrate-{{ checksum "Gemfile.lock" }}
paths:
- vendor/bundle
# Wait for DB
- run: dockerize -wait tcp://localhost:5432 -timeout 1m
# Setup the environment
- run: cp .sample.env .env
# Setup the database
- run: bundle exec rake db:setup
# Run the tests
- run: bundle exec rake
default_job: &default_job
working_directory: ~/administrate
steps:
- shared_steps
# Run the tests against multiple versions of Rails
- run: bundle exec appraisal install
- run: bundle exec appraisal rake
jobs:
ruby-25:
<<: *default_job
docker:
- image: circleci/ruby:2.5.0-node-browsers
environment:
PGHOST: localhost
PGUSER: administrate
RAILS_ENV: test
- image: postgres:10.1-alpine
environment:
POSTGRES_USER: administrate
POSTGRES_DB: ruby25
POSTGRES_PASSWORD: ""
ruby-26:
<<: *default_job
docker:
- image: circleci/ruby:2.6.3-node-browsers-legacy
environment:
PGHOST: localhost
PGUSER: administrate
RAILS_ENV: test
- image: postgres:10.1-alpine
environment:
POSTGRES_USER: administrate
POSTGRES_DB: ruby26
POSTGRES_PASSWORD: ""
workflows:
version: 2
multiple-rubies:
jobs:
- ruby-26
- ruby-25
Complete example for GitHub Actions
# This workflow uses actions that are not certified by GitHub.
# They are provided by a third-party and are governed by
# separate terms of service, privacy policy, and support
# documentation.
# GitHub recommends pinning actions to a commit SHA.
# To get a newer version, you will need to update the SHA.
# You can also reference a tag or branch, but the action may change without warning.
name: Containers
on: [push]
jobs:
build:
strategy:
matrix:
ruby: ['2.5', '2.6.3']
runs-on: ubuntu-latest
env:
PGHOST: localhost
PGUSER: administrate
RAILS_ENV: test
services:
postgres:
image: postgres:10.1-alpine
env:
POSTGRES_USER: administrate
POSTGRES_DB: ruby25
POSTGRES_PASSWORD: ""
ports:
- 5432:5432
# Add a health check
options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 5
steps:
- uses: actions/checkout@v4
- name: Setup Ruby
uses: eregon/use-ruby-action@ec02537da5712d66d4d50a0f33b7eb52773b5ed1
with:
ruby-version: ${{ matrix.ruby }}
- name: Cache dependencies
uses: actions/cache@v3
with:
path: vendor/bundle
key: administrate-${{ matrix.image }}-${{ hashFiles('Gemfile.lock') }}
- name: Install postgres headers
run: |
sudo apt-get update
sudo apt-get install libpq-dev
- name: Install dependencies
run: bundle install --path vendor/bundle
- name: Setup environment configuration
run: cp .sample.env .env
- name: Setup database
run: bundle exec rake db:setup
- name: Run tests
run: bundle exec rake
- name: Install appraisal
run: bundle exec appraisal install
- name: Run appraisal
run: bundle exec appraisal rake