Ecosystems:
JavaScript
watch-single-file-action-example
Example for a GitHub Action that acts on changes to a single file
How it works
The workflow is defined in .github/workflows/watch-file.yaml.
On every push event, index.js is run. The file that is being watched is passed as FILE_PATH_TO_WATCH environment variable. The payload from the push event includes two properties: "before" and "after", which ared use to find out which files have been changed using the Compare two commits endpoint. If the changed files include the file that is being watched, the "changed" output for the step is set to "true".
The next step can check for this output in order to act on the file change.