Runner Job Started/Completed Hooks

[fhammerl]

This PR implements Job Started and Job completed hooks for reuse. This functionality is in beta, and is subject to change over time.

Technical changes

• Add support for non-actions in ScriptHandler
• Add a HookProvider with provides job started/job end hooks for JobExtensionRunners to run
• Update our telemetry so we can see how many users are using this
• Add tests for this functionality

Description

This ADR describes the functionality in more detail, but at a high level:

• We will expose 2 variables that users can set to enable hooks
  • ACTIONS_RUNNER_HOOK_JOB_STARTED
  • ACTIONS_RUNNER_HOOK_JOB_COMPLETED

You can set these variables to the absolute path of a a .sh or .ps1 file.

We will execute pwsh (fallback to powershell) or bash (fallback to sh) as appropriate.

• .sh files will execute with the args -e {pathtofile}
• .ps1 files will execute with the args -command \". '{pathtofile}'\"

We will not set the standard flags we typically set for runs commands. So, if you want to set pipefail on bash for example, you will need to do that in your script.

UI

We want to ensure the experience for users invoking workflows is good, if hooks take too long, you may feel your job is delayed or broken. So, much like Set Up Job, we will generate two new steps automatically in your job, one for each configured hook:

• Set up runner
• Complete runner

[thboop]

Intentionally removing this, we shouldn't have a way to access this as a script step anyways but job extensions are going to try and use post stage script handlers

[ethomson]

Two minor comments but overall I'm excited to see this land. Great work.