Introduction
You can write an action to provide a way for users to access your servers via a configured CLI environment on GitHub Actions runners.
Your action should:
- Make it simple for users to specify the version of the CLI to install
- Support multiple operating systems
- Run in an efficient fashion to minimize run-time and associated costs
- Work across GitHub-hosted and self-hosted runners
- Leverage community tooling when possible
This article will demonstrate how to write an action that retrieves a specific version of your CLI, installs it, adds it to the path, and (optionally) caches it. This type of action (an action that sets up a tool) is often named setup-$TOOL.
Prerequisites
You should have an understanding of how to write a custom action. For more information, see Managing custom actions.
Example
The following script demonstrates how you can get a user-specified version as input, download and extract the specific version of your CLI, then add the CLI to the path.
GitHub provides actions/toolkit, which is a set of packages that helps you create actions. This example uses the actions/core and actions/tool-cache packages.
const core = require('@actions/core');
const tc = require('@actions/tool-cache');
async function setup() {
// Get version of tool to be installed
const version = core.getInput('version');
// Download the specific version of the tool, e.g. as a tarball
const pathToTarball = await tc.downloadTool(getDownloadURL());
// Extract the tarball onto the runner
const pathToCLI = await tc.extractTar(pathToTarball);
// Expose the tool by adding it to the PATH
core.addPath(pathToCLI)
}
module.exports = setup
const core = require('@actions/core');
const tc = require('@actions/tool-cache');
async function setup() {
// Get version of tool to be installed
const version = core.getInput('version');
// Download the specific version of the tool, e.g. as a tarball
const pathToTarball = await tc.downloadTool(getDownloadURL());
// Extract the tarball onto the runner
const pathToCLI = await tc.extractTar(pathToTarball);
// Expose the tool by adding it to the PATH
core.addPath(pathToCLI)
}
module.exports = setup
To use this script, replace getDownloadURL with a function that downloads your CLI. You will also need to create an actions metadata file (action.yml) that accepts a version input and that runs this script. For full details about how to create an action, see Creating a JavaScript action.
Further reading
This pattern is employed in several actions. For more examples, see: