What are all the hook types I can use in app.yml

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There isn’t actually a fixed global list of hook types in app.yml.
Hooks are provided dynamically by Pups, and you can only attach to the ones that exist inside the templates you include.

:magnifying_glass_tilted_left: How it works

When you see something like:

hooks:
  after_code:
    - exec:
        cd: $home/plugins
        cmd:
          - git clone https://github.com/discourse/docker_manager.git

that works because the templates contain a step like:

- hook: code
  run:
    - exec: ...

Pups lets you attach commands before or after any of those defined hook points.
So if a template defines hook: code, you can use before_code: or after_code:.
If it defines hook: assets_precompile, you can use before_assets_precompile: or after_assets_precompile: — and so on.

If there’s no hook: restart (for example), then after_restart: simply won’t fire.

:white_check_mark: Hooks known to exist in the stock templates

From the default templates/*.yml shipped with Discourse Docker:

Hook name Common usage Works with
code Main setup stage for plugin clones, custom file edits, etc. before_code: / after_code:
assets_precompile After Rails assets are compiled (e.g., upload to S3, clean up) after_assets_precompile:
web For last-minute tweaks before the web process boots before_web:

You’ll often see after_code: and before_code: used in plugin-install examples — these are the only ones needed in most setups.

:cross_mark: Hooks that don’t exist by default

Names like after_restart or after_post_boot don’t correspond to any hook: inside the standard templates, so Pups doesn’t know where to attach them.
They won’t trigger unless you add a matching hook: restart step in a custom template.

:toolbox: How to find all hooks available on your system

From your /var/discourse folder, run:

grep -R "hook:" -n templates/ samples/

That’ll list every hook name supported by the templates you currently include.
Anything you find there can be used as before_<name>: or after_<name>: inside your hooks: block.

:blue_book: Reference

This behaviour is explained briefly in the Pups README (the config-management tool used by Discourse’s Docker setup):

“Hooks are points in templates that allow commands to be injected before or after a step labelled with hook:.”

:puzzle_piece: In practice

  • Use after_code: for most custom shell commands (like plugin installs).
  • For things that should happen at container boot or restart, use a small startup script or supervisord task instead of inventing new hook names.
  • To add your own hook type, make a new template with a custom hook: something entry, then target it from app.yml.

TL;DR:
Only the hook names that actually appear as hook: entries in your templates exist.
In stock Discourse Docker, that’s basically code, assets_precompile, and web.

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