doc/packaging_apps_actions.md

Applications Actions

For now, all those features are EXPERIMENTAL and aren't ready for production and are probably going to change again, if you still decide to use them don't expect them to be stable and follow to core development of YunoHost otherwise they might randomly breaks on your apps

Applications "actions" is a packaging feature that allow you to ship with your application a list of "actions" executable from both the cli and the admin interfaces.

"actions" are a list of custom commands that, optionally, has arguments (like the installation script of an application has arguments) and once called will called a specific selected command with those arguments. Like an "actions" restart service with a argument "service name" could called the command systemctl restart $some_service (but don't that specific action in your app, it's just for example purpose).

Like the installation page generated from the manifest those actions can accept a list of arguments.

Their main purpose is to expose procedures that a sysadmin would normally do on CLI but that your application user would want to do but don't have the knowledge to do by themselves via ssh (or are just too lazy for that).

For example those could be:

• importing data in a application
• generate a custom backup
• start a procedure like synchronising file with the file system (nextcloud for example)
• purge a local cache
• restart some services
• modify a theme

Actions looks like this in the admin interface:

How to add actions to your application

Adding actions to your application is pretty simple as it is very similar to writing your manifest for the application installation.

You need to write an actions.toml file in your application at the root level like the manifest.toml/manifest.json.

The general pattern looks like this:

[first_action]
name = "some name"
description = "some description that will be displayed"

# can be a bash command like so:
command = "echo pouet $YNH_ACTION_FIRST_ARGUMENT"
# or a path to a script like
command = "/path/to/some/stuff --some-flag $YNH_ACTION_FIRST_ARGUMENT"

user = "root"  # optional
cwd = "/" # optional, "current working directory", by default it's "/etc/yunohost/apps/the_app_id"
          # also the variable "$app" is available in this variable and will be replace with the app id
          # for example you can write "/var/www/$app"
accepted_return_codes = [0, 1, 2, 3]  # optional otherwise only "0" will be a non enorous return code

    [first_action.arguments]
        # here, you put a list of arguments exactly like in manifest.toml/json
        [first_action.arguments.first_argument]
        type = "string"
        ask = "service to restart"
        example = "nginx"

        ...  # add more arguments here if needed
        # you can also have actions without arguments

[another_action]
name = "another name"
command = "systemctl restart some_service"

    [another_action.arguments]
        [another_action.arguments.argument_one]
        type = "string"
        ask = "some stuff"
        example = "stuff"

        ...  # add more arguments here if needed
        # you can also have actions without arguments

You can have as much actions as you want and from zero to as many arguments you want.

If you prefer, you can also write your actions in json like manifest.json:

[{
        "id": "restart_service",
        "name": "Restart service",
        "command": "echo pouet $YNH_ACTION_SERVICE",
        "user": "root",  # optional
        "cwd": "/", # optional
        "accepted_return_codes": [0, 1, 2, 3],  # optional
        "description": {
            "en": "a dummy stupid exemple or restarting a service"
        },
        "arguments": [
            {
                "name": "service",
                "type": "string",
                "ask": {
                    "en": "service to restart"
                },
                "example": "nginx"
            }
        ]
},
{
    ...  # other action
}]

How to use actions

In the admin

For now since those features are still experimental you won't find any direct links to the app actions on the app page

The actions are located on https://some_domain.tld/yunohost/admin/#/apps/$app_id/actions

With the CLI

The CLI API is very similar to application installation. You have 2 commands:

• yunohost app list $app
• yunohost app run $app $action_id ("$action_id" is the this between "[]" like "[another_action]" in the example)

list will obviously give you all actions for an application.

run will run an existing action for an application and will ask, if needed, values for arguments. Like with yunohost app install you can use the -a and pass arguments in the HTTP POST arguments format (like &path=/app&domain=domain.tld&other_value=stuff)