Plugin Creation
If you create your own plugin:
- Take a look at the plugins shipped with dokku and hack away!
- Check out the list of hooks your plugin can implement.
- Upload your plugin to github with a repository name in form of
dokku-<name>
(e.g.dokku-mariadb
) - Edit this page and add a link to it.
- Subscribe to the dokku development blog to be notified about API changes and releases
Sample plugin
The below plugin is a dummy dokku hello
plugin. If your plugin exposes commands, this is a good template for your commands
file:
#!/usr/bin/env bash
set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
source "$(dirname $0)/../common/functions"
case "$1" in
hello)
[[ -z $2 ]] && echo "Please specify an app to run the command on" && exit 1
verify_app_name "$2"
APP="$2";
echo "Hello $APP"
;;
hello:world)
echo "Hello world"
;;
help)
cat && cat<<EOF
hello <app>, Says "Hello <app>"
hello:world, Says "Hello world"
EOF
;;
*)
exit $DOKKU_NOT_IMPLEMENTED_EXIT
;;
esac
A few notes:
- You should always support
DOKKU_TRACE
as specified on the 2nd line of the plugin. - If your command requires that an application exists, ensure you check for it's existence in the manner prescribed above.
- A
help
command is required, though it is allowed to be empty. Also, the command syntax will need to separated by,
in order to maintain columnar output alignment. - Commands should be namespaced.
- As of 0.3.3, a catch-all should be implemented which exits with a
DOKKU_NOT_IMPLEMENTED_EXIT
code. This allows dokku to output acommand not found
message. -
Be sure you want the "set -eo pipefail" option. Look at the following example :
In the case where the "user/repo" is not installed, dokku exits just before the awk command, you will never see the message printed with echo. You just want "set -e" in this case.
Here is the documentation of the 'set -eo pipefail' option:
- As some plugins require access to set app config settings and do not want/require the default Heroku-style behavior of a restart, we have the following "internal" commands that provide this functionality :