An overview of when to use Docker container actions over JavaScript actions in GitHub and a deep dive into how to build one

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source: and

In my previous article, I described in detail the motivation behind GitHub Actions, their architecture, how events flow through GitHub, and how to create a custom GitHub Action from scratch using JavaScript.

I went over the two types of actions: JavaScript actions and Docker container actions. A lot of the open source actions I’ve explored are built using Javascript actions — perhaps for these reasons:

Learn about the architecture of actions, the two types of actions, and how to build a JavaScript action

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GitHub Logo

In my last article, I did an overview of GitHub Actions and demonstrated how to use an existing action to deploy a Gatsby site to GitHub Pages. In this post, I’d like to dive deeper into GitHub Actions exploring the underlying motivation behind them, the architecture, and the steps involved in building a custom action.

Before getting into the specifics of GitHub Actions, let’s understand the value they bring by first delving into GitHub events and how GitHub has been supporting the handling of these events.

GitHub Events

GitHub provides hosting for software projects and version control using Git. It has formed the nucleus of the software development lifecycle by supporting collaboration across teams (often distributed), code reviews, and project management. …

How to search for actions, keep the actions you depend on up to date, and release your own actions

Screenshot of GitHub marketplace
Screenshot of GitHub marketplace
GitHub Marketplace — Source

In my previous posts exploring GitHub Actions, I’ve delved into how to use public Actions on the GitHub Marketplace. In this post, I’d like to go over how to efficiently navigate the Marketplace as a developer.

Searching for Actions

There are two ways to search for public GitHub Actions.

Directly in the GitHub Marketplace

The GitHub Marketplace is home to two kinds of tools that extend GitHub’s core functionality:

To search for Actions directly in the GitHub Martketplace, you can filter by the Actions Type in the Sidebar.


Deborah Digges

Software Engineer, writer, and artist.

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