Allow to join an open group

Also:

* Refactor interacting with a remote event so that you can interact with
  a remote group as well
* Add a setting for group admins to pick between an open and invite-only
  group
* Fix new groups without posts/todos/resources/events/conversations URL
  set
* Repair local groups that haven't got their
  posts/todos/resources/events/conversations URL set
* Add a scheduled job to refresh remote groups every hour
* Add a user setting to pick when to receive notifications when there's
  new members to approve (will be used when this feature is available)
* Fix pagination for members

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/service/notifications/scheduler.ex

@@ -4,7 +4,7 @@ defmodule Mobilizon.Service.Notifications.Scheduler do
   """
 
   alias Mobilizon.{Actors, Users}
-  alias Mobilizon.Actors.Actor
+  alias Mobilizon.Actors.{Actor, Member}
   alias Mobilizon.Events.{Event, Participant}
   alias Mobilizon.Service.Workers.Notification
   alias Mobilizon.Users.{Setting, User}
@@ -193,6 +193,77 @@ defmodule Mobilizon.Service.Notifications.Scheduler do
 
   def pending_participation_notification(_), do: {:ok, nil}
 
+  def pending_membership_notification(%Actor{type: :Group, id: group_id}) do
+    group_id
+    |> Actors.list_all_administrator_members_for_group()
+    |> Enum.map(fn %Member{actor: %Actor{id: actor_id}} ->
+      Actors.get_actor(actor_id)
+    end)
+    |> Enum.each(fn actor -> pending_membership_admin_notification(actor, group_id) end)
+  end
+
+  def pending_membership_notification(_), do: {:ok, nil}
+
+  defp pending_membership_admin_notification(%Actor{user_id: user_id}, group_id)
+       when not is_nil(user_id) do
+    case Users.get_user_with_settings!(user_id) do
+      %User{} = user ->
+        pending_membership_admin_notification_user(user, group_id)
+
+      # No user for actor, probably a remote actor, ignore
+      _ ->
+        {:ok, nil}
+    end
+  end
+
+  defp pending_membership_admin_notification_user(
+         %User{
+           id: user_id,
+           locale: locale,
+           settings: %Setting{
+             notification_pending_membership: notification_pending_membership,
+             timezone: timezone
+           }
+         },
+         group_id
+       ) do
+    send_at =
+      case notification_pending_membership do
+        :none ->
+          nil
+
+        :direct ->
+          :direct
+
+        :one_day ->
+          calculate_next_day_notification(Date.utc_today(), timezone, locale)
+
+        :one_hour ->
+          DateTime.utc_now()
+          |> DateTime.shift_zone!(timezone)
+          |> (&%{&1 | minute: 0, second: 0, microsecond: {0, 0}}).()
+      end
+
+    params = %{
+      user_id: user_id,
+      group_id: group_id
+    }
+
+    cond do
+      # Sending directly
+      send_at == :direct ->
+        Notification.enqueue(:pending_membership_notification, params)
+
+      # Not sending
+      is_nil(send_at) ->
+        {:ok, nil}
+
+      # Sending to calculated time
+      true ->
+        Notification.enqueue(:pending_membership_notification, params, scheduled_at: send_at)
+    end
+  end
+
   defp shift_zone(datetime, timezone) do
     case DateTime.shift_zone(datetime, timezone) do
       {:ok, shift_datetime} -> shift_datetime

lib/service/workers/refresh_groups.ex

@@ -0,0 +1,12 @@
+defmodule Mobilizon.Service.Workers.RefreshGroups do
+  @moduledoc """
+  Worker to build sitemap
+  """
+
+  alias Mobilizon.Federation.ActivityPub.Refresher
+
+  use Oban.Worker, queue: "background"
+
+  @impl Oban.Worker
+  def perform(%Job{}), do: Refresher.refresh_all_external_groups()
+end