The application command behaviour specifies the interface that a slash, user, or message command module should implement.

Like regular commands, application command modules are stateless on their own. Implementations of the callbacks defined by this behaviour are invoked from other modules/functions, notably a Nosedrum.Interactor.

The types defined in this module reflect the official Application Command docs.

Example Slash Command

This command echos the passed message back to the user.

# In your application command module file, e.g. ./lib/my_app/commands/echo.ex
defmodule MyApp.Commands.Echo do
  @behaviour Nosedrum.ApplicationCommand

  @impl true
  def description() do
    "Echos a message."
  end

  @impl true
  def command(interaction) do
    [%{name: "message", value: message}] = interaction.data.options
    [
      content: message,
      ephemeral?: true
    ]
  end

  @impl true
  def type() do
    :slash
  end

  @impl true
  def options() do
    [
      %{
        type: :string,
        name: "message",
        description: "The message for the bot to echo.",
        required: true
      }
    ]
  end
end

# In your Nostrum.Consumer file, e.g. ./lib/my_app/consumer.ex
defmodule MyApp.Consumer do
  use Nostrum.Consumer

  # ...

  # You may use `:global` instead of a guild id at GUILD_ID_HERE, but note
  # that global commands could take up to an hour to become available.
  def handle_event({:READY, _data, _ws_state}) do
    case Nosedrum.Interactor.Dispatcher.add_command("echo", MyApp.Commands.Echo, GUILD_ID_HERE) do
      {:ok, _} -> IO.puts("Registered Echo command.")
      e -> IO.inspect(e, label: "An error occurred registering the Echo command")
    end
  end
end

You will also need to start the Nosedrum.Interactor.Dispatcher as part of your supervision tree, for example, by adding this to your application start function:

# ./lib/my_app/application.ex
defmodule MyApp.Application do
  # ...
  def start(type, args) do
    children = [
      # ...
      {Nosedrum.Interactor.Dispatcher, name: Nosedrum.Interactor.Dispatcher},
    ]

    options = [strategy: :rest_for_one, name: Bolt.Supervisor]
    Supervisor.start_link(children, options)
  end
end