Boot Hooks

Boot hooks are scripts which execute pre/post to events that occur in the run control script.

Events

• pre_configure, occurs before REPLACE_OS_VARS triggers replacement, and before any generated files are generated
• post_configure, currs after environment variable replacement and after generated files are generated
• pre_start, occurs before the release is started
• post_start, occurs right after the release is started
• pre_stop, occurs after a request to stop the release is issued, but before the release is stopped
• post_stop, occurs after the release is stopped

Example Usage

Given a config like the following:

use Mix.Releases.Config

environment :default do
  set pre_start_hook: "rel/hooks/pre_start"
  set post_start_hook: "rel/hooks/post_start"
end

release :myapp do
  set version: current_version(:myapp)
end

And the two hook scripts under rel/hooks:

# pre_start
echo "we're starting!"

# post_start
echo "we've started!"

When you build your release, and run it, you’ll see something like the following:

> _build/dev/rel/myapp/bin/myapp foreground
we're starting!
...snip...
we've started!
...snip...

You have access to anything defined in the run control script environment, see Shell Script API for details.