Add API to join and leave an event

lib/mobilizon_web/resolvers/event.ex

@@ -4,7 +4,7 @@ defmodule MobilizonWeb.Resolvers.Event do
   """
   alias Mobilizon.Service.ActivityPub
   alias Mobilizon.Activity
-  alias Mobilizon.Events.Event
+  alias Mobilizon.Events.{Event, Participant}
   alias Mobilizon.Actors.User
 
   # We limit the max number of events that can be retrieved
@@ -43,6 +43,78 @@ defmodule MobilizonWeb.Resolvers.Event do
     {:ok, Mobilizon.Events.list_participants_for_event(uuid, 1, 10)}
   end
 
+  @doc """
+  Join an event for an actor
+  """
+  def actor_join_event(
+        _parent,
+        %{actor_id: actor_id, event_id: event_id},
+        %{
+          context: %{
+            current_user: user
+          }
+        }
+      ) do
+    with {:is_owned, true, actor} <- User.owns_actor(user, actor_id),
+         {:ok, %Event{} = event} <- Mobilizon.Events.get_event(event_id),
+         {:error, :participant_not_found} <- Mobilizon.Events.get_participant(event_id, actor_id),
+         role <- Mobilizon.Events.get_default_participant_role(event),
+         {:ok, participant} <-
+           Mobilizon.Events.create_participant(%{
+             role: role,
+             event_id: event.id,
+             actor_id: actor.id
+           }),
+         participant <-
+           Map.put(participant, :event, event)
+           |> Map.put(:actor, actor) do
+      {:ok, participant}
+    else
+      {:is_owned, false} ->
+        {:error, "Actor id is not owned by authenticated user"}
+
+      {:error, :event_not_found} ->
+        {:error, "Event id not found"}
+
+      {:ok, %Participant{}} ->
+        {:error, "You are already a participant of this event"}
+    end
+  end
+
+  def actor_join_event(_parent, _args, _resolution) do
+    {:error, "You need to be logged-in to join an event"}
+  end
+
+  @doc """
+  Leave an event for an actor
+  """
+  def actor_leave_event(
+        _parent,
+        %{actor_id: actor_id, event_id: event_id},
+        %{
+          context: %{
+            current_user: user
+          }
+        }
+      ) 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
+      {:ok, %{event: %{id: event_id}, actor: %{id: actor_id}}}
+    else
+      {:is_owned, false} ->
+        {:error, "Actor id is not owned by authenticated user"}
+
+      {:error, :participant_not_found} ->
+        {:error, "Participant not found"}
+    end
+  end
+
+  def actor_leave_event(_parent, _args, _resolution) do
+    {:error, "You need to be logged-in to leave an event"}
+  end
+
   @doc """
   Search events by title
   """
@@ -103,7 +175,7 @@ defmodule MobilizonWeb.Resolvers.Event do
         context: %{current_user: user}
       }) do
     with {:ok, %Event{} = event} <- Mobilizon.Events.get_event(event_id),
-         {:is_owned, true} <- User.owns_actor(user, actor_id),
+         {:is_owned, true, _} <- User.owns_actor(user, actor_id),
          {:event_can_be_managed, true} <- Event.can_event_be_managed_by(event, actor_id),
          event <- Mobilizon.Events.delete_event!(event) do
       {:ok, %{id: event.id}}

lib/mobilizon_web/resolvers/group.ex

@@ -82,7 +82,7 @@ defmodule MobilizonWeb.Resolvers.Group do
         }
       ) do
     with {:ok, %Actor{} = group} <- Actors.find_group_by_actor_id(group_id),
-         {:is_owned, true} <- User.owns_actor(user, actor_id),
+         {:is_owned, true, _} <- User.owns_actor(user, actor_id),
          {:ok, %Member{} = member} <- Member.get_member(actor_id, group.id),
          {:is_admin, true} <- Member.is_administrator(member),
          group <- Actors.delete_group!(group) do

lib/mobilizon_web/schema.ex

@@ -143,6 +143,7 @@ defmodule MobilizonWeb.Schema do
     import_fields(:event_mutations)
     import_fields(:category_mutations)
     import_fields(:comment_mutations)
+    import_fields(:participant_mutations)
 
     # @desc "Upload a picture"
     # field :upload_picture, :picture do

lib/mobilizon_web/schema/actor.ex

@@ -12,7 +12,7 @@ defmodule MobilizonWeb.Schema.ActorInterface do
 
   @desc "An ActivityPub actor"
   interface :actor do
-    field(:id, :id, description: "Internal ID for this actor")
+    field(:id, :integer, description: "Internal ID for this actor")
     field(:url, :string, description: "The ActivityPub actor's URL")
     field(:type, :actor_type, description: "The type of Actor (Person, Group,…)")
     field(:name, :string, description: "The actor's displayed name")

lib/mobilizon_web/schema/actors/group.ex

@@ -13,7 +13,7 @@ defmodule MobilizonWeb.Schema.Actors.GroupType do
   object :group do
     interfaces([:actor])
 
-    field(:id, :id, description: "Internal ID for this group")
+    field(:id, :integer, description: "Internal ID for this group")
     field(:url, :string, description: "The ActivityPub actor's URL")
     field(:type, :actor_type, description: "The type of Actor (Person, Group,…)")
     field(:name, :string, description: "The actor's displayed name")

lib/mobilizon_web/schema/actors/person.ex

@@ -13,7 +13,7 @@ defmodule MobilizonWeb.Schema.Actors.PersonType do
   """
   object :person do
     interfaces([:actor])
-    field(:id, :id, description: "Internal ID for this person")
+    field(:id, :integer, description: "Internal ID for this person")
     field(:user, :user, description: "The user this actor is associated to")
 
     field(:member_of, list_of(:member), description: "The list of groups this person is member of")

lib/mobilizon_web/schema/event.ex

@@ -12,7 +12,7 @@ defmodule MobilizonWeb.Schema.EventType do
 
   @desc "An event"
   object :event do
-    field(:id, :id, description: "Internal ID for this event")
+    field(:id, :integer, description: "Internal ID for this event")
     field(:uuid, :uuid, description: "The Event UUID")
     field(:url, :string, description: "The ActivityPub Event URL")
     field(:local, :boolean, description: "Whether the event is local or not")

lib/mobilizon_web/schema/events/participant.ex

@@ -5,18 +5,34 @@ defmodule MobilizonWeb.Schema.Events.ParticipantType do
   use Absinthe.Schema.Notation
   import Absinthe.Resolution.Helpers, only: [dataloader: 1]
   alias MobilizonWeb.Resolvers
+  alias Mobilizon.Events
+  alias Mobilizon.Actors
 
   @desc "Represents a participant to an event"
   object :participant do
-    field(:event, :event,
+    field(
+      :event,
+      :event,
       resolve: dataloader(Events),
       description: "The event which the actor participates in"
     )
 
-    field(:actor, :actor, description: "The actor that participates to the event")
+    field(
+      :actor,
+      :actor,
+      resolve: dataloader(Actors),
+      description: "The actor that participates to the event"
+    )
+
     field(:role, :integer, description: "The role of this actor at this event")
   end
 
+  @desc "Represents a deleted participant"
+  object :deleted_participant do
+    field(:event, :deleted_object)
+    field(:actor, :deleted_object)
+  end
+
   object :participant_queries do
     @desc "Get all participants for an event uuid"
     field :participants, list_of(:participant) do
@@ -26,4 +42,22 @@ defmodule MobilizonWeb.Schema.Events.ParticipantType do
       resolve(&Resolvers.Event.list_participants_for_event/3)
     end
   end
+
+  object :participant_mutations do
+    @desc "Join an event"
+    field :join_event, :participant do
+      arg(:event_id, non_null(:integer))
+      arg(:actor_id, non_null(:integer))
+
+      resolve(&Resolvers.Event.actor_join_event/3)
+    end
+
+    @desc "Leave an event"
+    field :leave_event, :deleted_participant do
+      arg(:event_id, non_null(:integer))
+      arg(:actor_id, non_null(:integer))
+
+      resolve(&Resolvers.Event.actor_leave_event/3)
+    end
+  end
 end