Add backend for group invitations

For #887

lib/graphql/resolvers/invitation.ex

@@ -0,0 +1,57 @@
+defmodule Mobilizon.GraphQL.Resolvers.Invitation do
+  @moduledoc """
+  Handles the invitation-related GraphQL calls
+  """
+
+  alias Mobilizon.Actors
+  alias Mobilizon.Actors.Actor
+  alias Mobilizon.Invitations
+  import Mobilizon.Web.Gettext
+
+  defp authorize_group_admin(%Actor{id: actor_id}, group_id) do
+    if Actors.administrator?(actor_id, group_id) do
+      :ok
+    else
+      {:error, dgettext("errors", "Profile is not administrator for the group")}
+    end
+  end
+
+  def create_invitation(_parent, %{group_id: group_id} = args, %{
+        context: %{current_actor: %Actor{} = updater_actor}
+      }) do
+    with :ok <- authorize_group_admin(updater_actor, group_id),
+         {:ok, invitation} <- Invitations.create_invitation(args) do
+      {:ok, invitation}
+    else
+      {:error, _} ->
+        {:error, dgettext("errors", "could not create invitation")}
+
+      error ->
+        error
+    end
+  end
+
+  def list_invitations(_parent, %{group_id: group_id}, %{
+        context: %{current_actor: %Actor{} = updater_actor}
+      }) do
+    with :ok <- authorize_group_admin(updater_actor, group_id) do
+      {:ok, Invitations.list_invitations(group_id)}
+    end
+  end
+
+  def update_invitation(_parent, %{group_id: group_id, token: token} = args, %{
+        context: %{current_actor: %Actor{} = updater_actor}
+      }) do
+    with :ok <- authorize_group_admin(updater_actor, group_id) do
+      Invitations.update_invitation_by_token(group_id, token, args)
+    end
+  end
+
+  def delete_invitation(_parent, %{group_id: group_id, token: token}, %{
+        context: %{current_actor: %Actor{} = updater_actor}
+      }) do
+    with :ok <- authorize_group_admin(updater_actor, group_id) do
+      Invitations.delete_invitation_by_token(group_id, token)
+    end
+  end
+end