Events with only one event creator participant can't be left

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

lib/mobilizon/events/events.ex

@@ -582,6 +582,28 @@ defmodule Mobilizon.Events do
     )
   end
 
+  @doc """
+  Returns the list of organizers participants for an event.
+
+  ## Examples
+
+      iex> list_organizers_participants_for_event(id)
+      [%Participant{role: :creator}, ...]
+
+  """
+  def list_organizers_participants_for_event(id, page \\ nil, limit \\ nil) do
+    Repo.all(
+      from(
+        p in Participant,
+        join: e in Event,
+        on: p.event_id == e.id,
+        where: e.id == ^id and p.role == ^:creator,
+        preload: [:actor]
+      )
+      |> paginate(page, limit)
+    )
+  end
+
   @doc """
   Gets a single participant.
 

lib/mobilizon_web/resolvers/event.ex

@@ -100,12 +100,19 @@ defmodule MobilizonWeb.Resolvers.Event do
     with {:is_owned, true, _} <- User.owns_actor(user, actor_id),
          {:ok, %Participant{} = participant} <-
            Mobilizon.Events.get_participant(event_id, actor_id),
-         {:ok, _} <- Mobilizon.Events.delete_participant(participant) do
+         {:only_organizer, false} <-
+           {:only_organizer,
+            Mobilizon.Events.list_organizers_participants_for_event(event_id) |> length == 1},
+         {:ok, _} <-
+           Mobilizon.Events.delete_participant(participant) do
       {:ok, %{event: %{id: event_id}, actor: %{id: actor_id}}}
     else
       {:is_owned, false} ->
         {:error, "Actor id is not owned by authenticated user"}
 
+      {:only_organizer, true} ->
+        {:error, "You can't leave event because you're the only event creator participant"}
+
       {:error, :participant_not_found} ->
         {:error, "Participant not found"}
     end

test/mobilizon_web/resolvers/participant_resolver_test.exs

@@ -46,7 +46,7 @@ defmodule MobilizonWeb.Resolvers.ParticipantResolverTest do
         |> post("/api", AbsintheHelpers.mutation_skeleton(mutation))
 
       assert json_response(res, 200)["errors"] == nil
-      assert json_response(res, 200)["data"]["joinEvent"]["role"] == 1
+      assert json_response(res, 200)["data"]["joinEvent"]["role"] == "participant"
       assert json_response(res, 200)["data"]["joinEvent"]["event"]["id"] == event.id
       assert json_response(res, 200)["data"]["joinEvent"]["actor"]["id"] == actor.id
 
@@ -122,6 +122,63 @@ defmodule MobilizonWeb.Resolvers.ParticipantResolverTest do
       conn: conn,
       user: user,
       actor: actor
+    } do
+      event = insert(:event, %{organizer_actor: actor})
+      participant = insert(:participant, %{actor: actor, event: event})
+      participant2 = insert(:participant, %{event: event})
+
+      mutation = """
+          mutation {
+            leaveEvent(
+              actor_id: #{participant.actor.id},
+              event_id: #{event.id}
+            ) {
+                actor {
+                  id
+                },
+                event {
+                  id
+                }
+              }
+            }
+      """
+
+      res =
+        conn
+        |> auth_conn(user)
+        |> post("/api", AbsintheHelpers.mutation_skeleton(mutation))
+
+      assert json_response(res, 200)["errors"] == nil
+      assert json_response(res, 200)["data"]["leaveEvent"]["event"]["id"] == event.id
+      assert json_response(res, 200)["data"]["leaveEvent"]["actor"]["id"] == participant.actor.id
+
+      query = """
+      {
+        participants(uuid: "#{event.uuid}") {
+          role,
+          actor {
+              preferredUsername
+          }
+        }
+      }
+      """
+
+      res =
+        conn
+        |> get("/api", AbsintheHelpers.query_skeleton(query, "participants"))
+
+      assert json_response(res, 200)["data"]["participants"] == [
+               %{
+                 "actor" => %{"preferredUsername" => participant2.actor.preferred_username},
+                 "role" => "creator"
+               }
+             ]
+    end
+
+    test "actor_leave_event/3 should check if the participant is the only creator", %{
+      conn: conn,
+      actor: actor,
+      user: user
     } do
       participant = insert(:participant, %{actor: actor})
 
@@ -146,9 +203,35 @@ defmodule MobilizonWeb.Resolvers.ParticipantResolverTest do
         |> auth_conn(user)
         |> post("/api", AbsintheHelpers.mutation_skeleton(mutation))
 
-      assert json_response(res, 200)["errors"] == nil
+      assert hd(json_response(res, 200)["errors"])["message"] ==
-      assert json_response(res, 200)["data"]["leaveEvent"]["event"]["id"] == participant.event.id
+               "You can't leave event because you're the only event creator participant"
-      assert json_response(res, 200)["data"]["leaveEvent"]["actor"]["id"] == participant.actor.id
+
+      # If we have a second participant but not an event creator
+      insert(:participant, %{event: participant.event, role: :participant})
+
+      mutation = """
+          mutation {
+            leaveEvent(
+              actor_id: #{participant.actor.id},
+              event_id: #{participant.event.id}
+            ) {
+                actor {
+                  id
+                },
+                event {
+                  id
+                }
+              }
+            }
+      """
+
+      res =
+        conn
+        |> auth_conn(user)
+        |> post("/api", AbsintheHelpers.mutation_skeleton(mutation))
+
+      assert hd(json_response(res, 200)["errors"])["message"] ==
+               "You can't leave event because you're the only event creator participant"
     end
 
     test "actor_leave_event/3 should check the user is logged in", %{conn: conn, actor: actor} do
@@ -258,7 +341,7 @@ defmodule MobilizonWeb.Resolvers.ParticipantResolverTest do
       assert json_response(res, 200)["data"]["participants"] == [
                %{
                  "actor" => %{"preferredUsername" => context.actor.preferred_username},
-                 "role" => 4
+                 "role" => "creator"
                }
              ]
 
@@ -266,7 +349,7 @@ defmodule MobilizonWeb.Resolvers.ParticipantResolverTest do
       actor2 = insert(:actor)
       actor3 = insert(:actor)
       # This one won't get listed (as not approved)
-      participant = insert(:participant, event: event, actor: actor2, role: :not_approved)
+      insert(:participant, event: event, actor: actor2, role: :not_approved)
       # This one will (as a participant)
       participant2 = insert(:participant, event: event, actor: actor3, role: :participant)