Git Hub Actions

by

Simon Hofmann

-

2019-02-20

Overview

• Intro
• How do GitHub Actions work?
• What are GitHub Actions Good For?
• act
• Resources

Intro

GitHub Actions

GitHub Actions

• Allow to implement custom logic on GitHub
• Fully integrated, no external app required
• Graphical editor and / or text based editing
• Veeeeery flexible!
• Still invite only beta 😭

Hooray!

How do GitHub Actions work?

triggers

• Actions are triggered by GitHub events
• create
• issue
• pull_request
• push
• and more...

workflow

• Workflows map events to actions
• Sample:

  							
  								workflow "Build and deploy to gh-pages" {
  									on = "push"
  									resolves = [
  										"Deploy if on master",
  										"Test",
  										"Production build && Deploy",
  									]
  								}
  							
  						

resolves

• When a workflow executes, one or more actions may be resolved
• Resolving means to execute every (transitive) dependency of an action
• If one action fails, no subsequent actions will be executed

actions

• Working parts of a workflow
• Running in Docker containers
• Sample:

  							
  								action "Production build && Deploy" {
  									uses = "docker://node:10"
  									needs = ["Deploy if on master"]
  									secrets = [
  										"DEPLOY_USER",
  										"GITHUB_TOKEN",
  									]
  									runs = "npm run deploy"
  								}
  							
  						

uses

• Specifies what to actually run
• Multiple sources supported
• ./path: Specifies the path to a Dockerfile in current repo
• owner/repo/path@ref: Reference another GitHub repo containing an action
• docker://image: References a Docker image

needs

• Specifies dependencies
• Chains actions to form a "pipeline"

runs

• Specifies which command to run in the Docker container

args

• Specifies which parameters to append to the "runs" command

env

• Allows to configure container environment variables
• "ENV"

secrets

• Allows to inject secrets as environment variables
• Created via Web UI
• Stored encrypted, no plain-text passwords

What are GitHub Actions good for?

CI / CD

• Build and deploy to GitHub Pages
• Deploy to any (major) cloud provider
• AWS, Azure, netlify, etc.
• Publish artifacts
• npm, Maven Central etc.

Workflow automation

• Cleanup branches
• Apply labels
• Auto rebase
• Auto PR
• etc ...

Notifications

• Slack
• Twitter
• Email
• etc ...

act

act

• Run your GitHub Actions locally!
• Run full workflow
• Or just single steps

act

• Experiment locally!
• Run default event (push)
• Or a specific one

act

Resources

• GitHub Actions Docs
• GitHub Actions Language Spec
• Official Actions Collection
• Awesome GitHub Actions
• act

That's it!

Thank's for your attention!

Questions?

Or feedback?