wip events

Signed-off-by: marcin mikołajczak <git@mkljczk.pl>

lib/pleroma/constants.ex

@@ -19,7 +19,9 @@ defmodule Pleroma.Constants do
       "context_id",
       "deleted_activity_id",
       "pleroma_internal",
-      "generator"
+      "generator",
+      "participants",
+      "participant_count"
     ]
   )
 

lib/pleroma/web/activity_pub/builder.ex

@@ -19,6 +19,30 @@ defmodule Pleroma.Web.ActivityPub.Builder do
 
   require Pleroma.Constants
 
+  def accept_or_reject(%User{ap_id: ap_id}, activity, type) do
+    data = %{
+      "id" => Utils.generate_activity_id(),
+      "actor" => ap_id,
+      "type" => type,
+      "object" => activity.data["id"],
+      "to" => [activity.actor]
+    }
+
+    {:ok, data, []}
+  end
+
+  def accept_or_reject(%Object{data: %{"actor" => actor}} = object, activity, type) do
+    data = %{
+      "id" => Utils.generate_activity_id(),
+      "actor" => actor,
+      "type" => type,
+      "object" => activity.data["id"],
+      "to" => [activity.actor]
+    }
+
+    {:ok, data, []}
+  end
+
   def accept_or_reject(actor, activity, type) do
     data = %{
       "id" => Utils.generate_activity_id(),
@@ -31,14 +55,14 @@ def accept_or_reject(actor, activity, type) do
     {:ok, data, []}
   end
 
-  @spec reject(User.t(), Activity.t()) :: {:ok, map(), keyword()}
-  def reject(actor, rejected_activity) do
-    accept_or_reject(actor, rejected_activity, "Reject")
+  @spec reject(User.t() | Object.t(), Activity.t()) :: {:ok, map(), keyword()}
+  def reject(object, rejected_activity) do
+    accept_or_reject(object, rejected_activity, "Reject")
   end
 
-  @spec accept(User.t(), Activity.t()) :: {:ok, map(), keyword()}
-  def accept(actor, accepted_activity) do
-    accept_or_reject(actor, accepted_activity, "Accept")
+  @spec accept(User.t() | Object.t(), Activity.t()) :: {:ok, map(), keyword()}
+  def accept(object, accepted_activity) do
+    accept_or_reject(object, accepted_activity, "Accept")
   end
 
   @spec follow(User.t(), User.t()) :: {:ok, map(), keyword()}
@@ -337,4 +361,14 @@ def unpin(%User{} = user, object) do
   defp pinned_url(nickname) when is_binary(nickname) do
     Pleroma.Web.Router.Helpers.activity_pub_url(Pleroma.Web.Endpoint, :pinned, nickname)
   end
+
+  def join(actor, object) do
+    with {:ok, data, meta} <- object_action(actor, object) do
+      data =
+        data
+        |> Map.put("type", "Join")
+
+      {:ok, data, meta}
+    end
+  end
 end

lib/pleroma/web/activity_pub/object_validator.ex

@@ -30,6 +30,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidator do
   alias Pleroma.Web.ActivityPub.ObjectValidators.EmojiReactValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.EventValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.FollowValidator
+  alias Pleroma.Web.ActivityPub.ObjectValidators.JoinValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.LikeValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.QuestionValidator
   alias Pleroma.Web.ActivityPub.ObjectValidators.UndoValidator
@@ -143,7 +144,7 @@ def validate(%{"type" => type} = object, meta)
 
   def validate(%{"type" => type} = object, meta)
       when type in ~w[Accept Reject Follow Update Like EmojiReact Announce
-      ChatMessage Answer] do
+      ChatMessage Answer Join] do
     validator =
       case type do
         "Accept" -> AcceptRejectValidator
@@ -155,6 +156,7 @@ def validate(%{"type" => type} = object, meta)
         "Announce" -> AnnounceValidator
         "ChatMessage" -> ChatMessageValidator
         "Answer" -> AnswerValidator
+        "Join" -> JoinValidator
       end
 
     with {:ok, object} <-

lib/pleroma/web/activity_pub/object_validators/accept_reject_validator.ex

@@ -6,6 +6,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.AcceptRejectValidator do
   use Ecto.Schema
 
   alias Pleroma.Activity
+  alias Pleroma.Object
 
   import Ecto.Changeset
   import Pleroma.Web.ActivityPub.ObjectValidators.CommonValidations
@@ -32,7 +33,7 @@ defp validate_data(cng) do
     |> validate_required([:id, :type, :actor, :to, :cc, :object])
     |> validate_inclusion(:type, ["Accept", "Reject"])
     |> validate_actor_presence()
-    |> validate_object_presence(allowed_types: ["Follow"])
+    |> validate_object_presence(allowed_types: ["Follow", "Join"])
     |> validate_accept_reject_rights()
   end
 
@@ -44,8 +45,8 @@ def cast_and_validate(data) do
 
   def validate_accept_reject_rights(cng) do
     with object_id when is_binary(object_id) <- get_field(cng, :object),
-         %Activity{data: %{"object" => followed_actor}} <- Activity.get_by_ap_id(object_id),
-         true <- followed_actor == get_field(cng, :actor) do
+         activity <- Activity.get_by_ap_id(object_id),
+         true <- validate_actor(activity, get_field(cng, :actor)) do
       cng
     else
       _e ->
@@ -53,4 +54,13 @@ def validate_accept_reject_rights(cng) do
         |> add_error(:actor, "can't accept or reject the given activity")
     end
   end
+
+  defp validate_actor(%Activity{data: %{"type" => "Follow", "object" => followed_actor}}, actor) do
+    followed_actor == actor
+  end
+
+  defp validate_actor(%Activity{data: %{"type" => "Join", "object" => joined_event}}, actor) do
+    %Object{data: %{"actor" => event_author}} = Object.get_cached_by_ap_id(joined_event)
+    event_author == actor
+  end
 end

lib/pleroma/web/activity_pub/object_validators/common_fields.ex

@@ -72,6 +72,8 @@ defmacro event_object_fields do
       field(:startTime, ObjectValidators.DateTime)
       field(:endTime, ObjectValidators.DateTime)
 
+      field(:joinMode, :string, default: "free")
+
       embeds_one(:location, PlaceValidator)
     end
   end

lib/pleroma/web/activity_pub/object_validators/event_validator.ex

@@ -64,6 +64,7 @@ def changeset(struct, data) do
   defp validate_data(data_cng) do
     data_cng
     |> validate_inclusion(:type, ["Event"])
+    |> validate_inclusion(:joinMode, ~w[free restricted invite])
     |> validate_required([:id, :actor, :attributedTo, :type, :context, :context_id])
     |> CommonValidations.validate_any_presence([:cc, :to])
     |> CommonValidations.validate_fields_match([:actor, :attributedTo])

lib/pleroma/web/activity_pub/object_validators/join_validator.ex

@@ -0,0 +1,87 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.ActivityPub.ObjectValidators.JoinValidator do
+  use Ecto.Schema
+
+  alias Pleroma.Object
+  alias Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes
+  alias Pleroma.Web.ActivityPub.Utils
+
+  import Ecto.Changeset
+  import Pleroma.Web.ActivityPub.ObjectValidators.CommonValidations
+
+  @primary_key false
+
+  embedded_schema do
+    quote do
+      unquote do
+        import Elixir.Pleroma.Web.ActivityPub.ObjectValidators.CommonFields
+        message_fields()
+        activity_fields()
+      end
+    end
+
+    field(:state, :string, default: "pending")
+
+    field(:participationMessage, :string)
+  end
+
+  def cast_data(data) do
+    data =
+      data
+      |> fix()
+
+    %__MODULE__{}
+    |> changeset(data)
+  end
+
+  def changeset(struct, data) do
+    struct
+    |> cast(data, __schema__(:fields))
+  end
+
+  defp fix(data) do
+    data =
+      data
+      |> CommonFixes.fix_actor()
+      |> CommonFixes.fix_activity_addressing()
+
+    with %Object{} = object <- Object.normalize(data["object"]) do
+      data
+      |> CommonFixes.fix_activity_context(object)
+      |> CommonFixes.fix_object_action_recipients(object)
+    else
+      _ -> data
+    end
+  end
+
+  defp validate_data(data_cng) do
+    data_cng
+    |> validate_inclusion(:type, ["Join"])
+    |> validate_inclusion(:state, ~w{pending reject accept})
+    |> validate_required([:id, :type, :object, :actor, :context, :to, :cc])
+    |> validate_actor_presence()
+    |> validate_object_presence(allowed_types: ["Event"])
+    |> validate_existing_join()
+  end
+
+  def cast_and_validate(data) do
+    data
+    |> cast_data()
+    |> validate_data()
+  end
+
+  defp validate_existing_join(%{changes: %{actor: actor, object: object}} = cng) do
+    if Utils.get_existing_join(actor, %{data: %{"id" => object}}) do
+      cng
+      |> add_error(:actor, "already joined this event")
+      |> add_error(:object, "already joined by this actor")
+    else
+      cng
+    end
+  end
+
+  defp validate_existing_join(cng), do: cng
+end

lib/pleroma/web/activity_pub/side_effects.ex

@@ -46,19 +46,14 @@ def handle(
           data: %{
             "actor" => actor,
             "type" => "Accept",
-            "object" => follow_activity_id
+            "object" => activity_id
           }
         } = object,
         meta
       ) do
-    with %Activity{actor: follower_id} = follow_activity <-
-           Activity.get_by_ap_id(follow_activity_id),
-         %User{} = followed <- User.get_cached_by_ap_id(actor),
-         %User{} = follower <- User.get_cached_by_ap_id(follower_id),
-         {:ok, follow_activity} <- Utils.update_follow_state_for_all(follow_activity, "accept"),
-         {:ok, _follower, followed} <-
-           FollowingRelationship.update(follower, followed, :follow_accept) do
-      Notification.update_notification_type(followed, follow_activity)
+    with %Activity{} = activity <-
+           Activity.get_by_ap_id(activity_id) do
+      handle_accepted(activity, actor)
     end
 
     {:ok, object, meta}
@@ -74,21 +69,63 @@ def handle(
           data: %{
             "actor" => actor,
             "type" => "Reject",
-            "object" => follow_activity_id
+            "object" => activity_id
           }
         } = object,
         meta
       ) do
-    with %Activity{actor: follower_id} = follow_activity <-
-           Activity.get_by_ap_id(follow_activity_id),
-         %User{} = followed <- User.get_cached_by_ap_id(actor),
+    with %Activity{actor: follower_id} = activity <-
+           Activity.get_by_ap_id(activity_id) do
+      handle_rejected(activity, actor)
+    end
+
+    {:ok, object, meta}
+  end
+
+  defp handle_accepted(
+         %Activity{actor: follower_id, data: %{"type" => "Follow"}} = follow_activity,
+         actor
+       ) do
+    with %User{} = followed <- User.get_cached_by_ap_id(actor),
+         %User{} = follower <- User.get_cached_by_ap_id(follower_id),
+         {:ok, follow_activity} <- Utils.update_follow_state_for_all(follow_activity, "accept"),
+         {:ok, _follower, followed} <-
+           FollowingRelationship.update(follower, followed, :follow_accept) do
+      Notification.update_notification_type(followed, follow_activity)
+    end
+  end
+
+  defp handle_accepted(
+         %Activity{data: %{"type" => "Join", "object" => event_id}} = join_activity,
+         _actor
+       ) do
+    with joined_event <- Object.get_by_ap_id(event_id),
+         {:o, join_activity} <- Utils.update_follow_state(join_activity, "accept") do
+      Utils.add_participation_to_object(join_activity, joined_event)
+      # Notification.update_notification_type(followed, follow_activity)
+    end
+  end
+
+  defp handle_rejected(
+         %Activity{actor: follower_id, data: %{"type" => "Follow"}} = follow_activity,
+         actor
+       ) do
+    with %User{} = followed <- User.get_cached_by_ap_id(actor),
          %User{} = follower <- User.get_cached_by_ap_id(follower_id),
          {:ok, _follow_activity} <- Utils.update_follow_state_for_all(follow_activity, "reject") do
       FollowingRelationship.update(follower, followed, :follow_reject)
       Notification.dismiss(follow_activity)
     end
+  end
 
-    {:ok, object, meta}
+  defp handle_rejected(
+         %Activity{data: %{"type" => "Join", "object" => event_id}} = join_activity,
+         _actor
+       ) do
+    with joined_event <- Object.get_by_ap_id(event_id),
+         {:o, join_activity} <- Utils.update_join_state(join_activity, "reject") do
+      Utils.remove_participation_from_object(join_activity, joined_event)
+    end
   end
 
   # Tasks this handle
@@ -384,6 +421,20 @@ def handle(%{data: %{"type" => "Remove"} = data} = object, meta) do
     end
   end
 
+  # Tasks this handles:
+  # accepts join if event is local
+  @impl true
+  def handle(%{data: %{"type" => "Join"}} = object, meta) do
+    joined_event = Object.get_by_ap_id(object.data["object"])
+
+    if Object.local?(joined_event) and joined_event.data["joinMode"] == "free" do
+      {:ok, accept_data, _} = Builder.accept(joined_event, object)
+      {:ok, _activity, _} = Pipeline.common_pipeline(accept_data, local: true)
+    end
+
+    {:ok, object, meta}
+  end
+
   # Nothing to do
   @impl true
   def handle(object, meta) do

lib/pleroma/web/activity_pub/utils.ex

@@ -432,6 +432,29 @@ defp fetch_likes(object) do
     end
   end
 
+  def add_participation_to_object(%Activity{data: %{"actor" => actor}}, object) do
+    [actor | fetch_participations(object)]
+    |> Enum.uniq()
+    |> update_participations_in_object(object)
+  end
+
+  def remove_participation_from_object(%Activity{data: %{"actor" => actor}}, object) do
+    List.delete(fetch_participations(object), actor)
+    |> update_participations_in_object(object)
+  end
+
+  defp update_participations_in_object(participations, object) do
+    update_element_in_object("participation", participations, object)
+  end
+
+  defp fetch_participations(object) do
+    if is_list(object.data["participations"]) do
+      object.data["participations"]
+    else
+      []
+    end
+  end
+
   #### Follow-related helpers
 
   @doc """
@@ -887,4 +910,26 @@ def get_existing_votes(actor, %{data: %{"id" => id}}) do
     |> where([a, object: o], fragment("(?)->>'type' = 'Answer'", o.data))
     |> Repo.all()
   end
+
+  ### Join-related helpers
+  def get_existing_join(actor, %{data: %{"id" => id}}) do
+    actor
+    |> Activity.Queries.by_actor()
+    |> Activity.Queries.by_object_id(id)
+    |> Activity.Queries.by_type("Join")
+    |> limit(1)
+    |> Repo.one()
+  end
+
+  def update_join_state(
+        %Activity{} = activity,
+        state
+      ) do
+    new_data = Map.put(activity.data, "state", state)
+    changeset = Changeset.change(activity, data: new_data)
+
+    with {:ok, activity} <- Repo.update(changeset) do
+      {:ok, activity}
+    end
+  end
 end

lib/pleroma/web/api_spec/operations/pleroma_event_operation.ex

@@ -0,0 +1,100 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.ApiSpec.PleromaEventOperation do
+  alias OpenApiSpex.Operation
+  alias OpenApiSpex.Schema
+  alias Pleroma.Web.ApiSpec.Schemas.ApiError
+  alias Pleroma.Web.ApiSpec.Schemas.FlakeID
+  alias Pleroma.Web.ApiSpec.Schemas.Status
+
+  import Pleroma.Web.ApiSpec.Helpers
+
+  def open_api_operation(action) do
+    operation = String.to_existing_atom("#{action}_operation")
+    apply(__MODULE__, operation, [])
+  end
+
+  def create_operation do
+    %Operation{
+      tags: ["Event actions"],
+      summary: "Publish new status",
+      security: [%{"oAuth" => ["write"]}],
+      description: "Create a new event",
+      operationId: "PleromaAPI.EventController.create",
+      requestBody: request_body("Parameters", create_request(), required: true),
+      responses: %{
+        200 => event_response(),
+        422 => Operation.response("Bad Request", "application/json", ApiError)
+      }
+    }
+  end
+
+  def participate_operation do
+    %Operation{
+      tags: ["Event actions"],
+      summary: "Participate",
+      security: [%{"oAuth" => ["write"]}],
+      description: "Participate in an event",
+      operationId: "PleromaAPI.EventController.participate",
+      parameters: [id_param()],
+      responses: %{
+        200 => event_response(),
+        404 => Operation.response("Not Found", "application/json", ApiError)
+      }
+    }
+  end
+
+  defp create_request do
+    %Schema{
+      title: "EventCreateRequest",
+      type: :object,
+      properties: %{
+        name: %Schema{
+          type: :string,
+          description: "Name of the event."
+        },
+        content: %Schema{
+          type: :string,
+          description: "Text description of the event."
+        },
+        start_time: %Schema{
+          type: :string,
+          format: :"date-time",
+          description: "Start time."
+        },
+        end_time: %Schema{
+          type: :string,
+          format: :"date-time",
+          description: "End time."
+        },
+        join_mode: %Schema{
+          type: :string,
+          enum: ["free", "restricted"]
+        }
+      },
+      example: %{
+        "name" => "Example event",
+        "content" => "No information for now.",
+        "start_time" => "21-02-2022 22:00:00",
+        "end_time" => "21-02-2022 23:00:00"
+      }
+    }
+  end
+
+  defp event_response do
+    Operation.response(
+      "Status",
+      "application/json",
+      Status
+    )
+  end
+
+  defp id_param do
+    Operation.parameter(:id, :path, FlakeID, "Event ID",
+      example: "9umDrYheeY451cQnEe",
+      required: true
+    )
+  end
+end

lib/pleroma/web/common_api.ex

@@ -304,6 +304,43 @@ def vote(user, %{data: %{"type" => "Question"}} = object, choices) do
     end
   end
 
+  def join(%User{} = user, id) do
+    case join_helper(user, id) do
+      {:ok, _} = res ->
+        res
+
+      {:error, :not_found} = res ->
+        res
+
+      {:error, e} ->
+        Logger.error("Could not join #{id}. Error: #{inspect(e, pretty: true)}")
+        {:error, dgettext("errors", "Could not join")}
+    end
+  end
+
+  def join_helper(user, id) do
+    with {_, %Activity{object: object}} <- {:find_object, Activity.get_by_id_with_object(id)},
+         {_, {:ok, join_object, meta}} <- {:build_object, Builder.join(user, object)},
+         {_, {:ok, %Activity{} = activity, _meta}} <-
+           {:common_pipeline,
+            Pipeline.common_pipeline(join_object, Keyword.put(meta, :local, true))} do
+      {:ok, activity}
+    else
+      {:find_object, _} ->
+        {:error, :not_found}
+
+      {:common_pipeline, {:error, {:validate, {:error, changeset}}}} = e ->
+        if {:object, {"already joined by this actor", []}} in changeset.errors do
+          {:ok, :already_joined}
+        else
+          {:error, e}
+        end
+
+      e ->
+        {:error, e}
+    end
+  end
+
   defp validate_not_author(%{data: %{"actor" => ap_id}}, %{ap_id: ap_id}),
     do: {:error, dgettext("errors", "Poll's author can't vote")}
 
@@ -598,4 +635,10 @@ def get_user(ap_id, fake_record_fallback \\ true) do
         nil
     end
   end
+
+  def event(user, data) do
+    with {:ok, draft} <- ActivityDraft.event(user, data) do
+      ActivityPub.create(draft.changes)
+    end
+  end
 end

lib/pleroma/web/common_api/activity_draft.ex

@@ -88,6 +88,32 @@ defp listen_object(draft) do
     %__MODULE__{draft | object: object}
   end
 
+  def event(user, params) do
+    user
+    |> new(params)
+    |> visibility()
+    |> to_and_cc()
+    |> context()
+    |> event_object()
+    |> with_valid(&changes/1)
+    |> validate()
+  end
+
+  defp event_object(draft) do
+    object =
+      draft.params
+      |> Map.take([:title, :content])
+      |> Map.put("type", "Event")
+      |> Map.put("to", draft.to)
+      |> Map.put("cc", draft.cc)
+      |> Map.put("actor", draft.user.ap_id)
+      |> Map.put("startTime", draft.params[:start_time])
+      |> Map.put("endTime", draft.params[:end_time])
+      |> Map.put("joinMode", draft.params[:join_mode])
+
+    %__MODULE__{draft | object: object}
+  end
+
   defp put_params(draft, params) do
     params = Map.put_new(params, :in_reply_to_status_id, params[:in_reply_to_id])
     %__MODULE__{draft | params: params}

lib/pleroma/web/mastodon_api/views/status_view.ex

@@ -562,6 +562,8 @@ def build_event(%{"type" => "Event"} = data) do
     %{
       start_time: data["startTime"],
       end_time: data["endTime"],
+      join_mode: data["joinMode"],
+      participants_count: data["participant_count"]
     }
   end
 

lib/pleroma/web/pleroma_api/controllers/event_controller.ex

@@ -0,0 +1,77 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.PleromaAPI.EventController do
+  use Pleroma.Web, :controller
+
+  import Pleroma.Web.ControllerHelper,
+    only: [try_render: 3]
+
+  alias Pleroma.Activity
+  alias Pleroma.Web.MastodonAPI.StatusView
+  alias Pleroma.Web.Plugs.OAuthScopesPlug
+  alias Pleroma.Web.CommonAPI
+
+  plug(Pleroma.Web.ApiSpec.CastAndValidate)
+
+  plug(
+    OAuthScopesPlug,
+    %{scopes: ["write"]}
+    when action in [:create, :participate]
+  )
+
+  defdelegate open_api_operation(action), to: Pleroma.Web.ApiSpec.PleromaEventOperation
+
+  def create(%{assigns: %{user: user}, body_params: params} = conn, _) do
+    with {:ok, activity} <- CommonAPI.event(user, params) do
+      conn
+      |> put_view(StatusView)
+      |> try_render("show.json",
+        activity: activity,
+        for: user,
+        as: :activity
+      )
+    else
+      {:error, {:reject, message}} ->
+        conn
+        |> put_status(:unprocessable_entity)
+        |> json(%{error: message})
+
+      {:error, message} ->
+        conn
+        |> put_status(:unprocessable_entity)
+        |> json(%{error: message})
+    end
+  end
+
+  def participations(conn, %{"id" => activity_id}) do
+  end
+
+  def participation_requests(conn, %{"id" => activity_id}) do
+    %Activity{object: %Object{data: %{"id" => ap_id}}} = activity <-
+      Activity.get_by_id_with_object(activity_id)
+
+    params =
+      params
+      |> Map.put(:type, "Join")
+      |> Map.put(:object, ap_id)
+      |> Map.put(:state, "pending")
+
+    activities =
+      recipients
+      |> ActivityPub.fetch_activities(params)
+      |> Enum.reverse()
+
+
+  end
+
+  def participate(%{assigns: %{user: user}} = conn, %{"id" => activity_id}) do
+    with {:ok, _} <- CommonAPI.join(user, activity_id),
+         %Activity{} = activity <- Activity.get_by_id(activity_id) do
+      conn
+      |> put_view(StatusView)
+      |> try_render("show.json", activity: activity, for: user, as: :activity)
+    end
+  end
+end

lib/pleroma/web/pleroma_api/views/event_view.ex

@@ -0,0 +1,24 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.PleromaAPI.EventView do
+  use Pleroma.Web, :view
+  alias Pleroma.Web.MastodonAPI
+
+  def render(
+        "participation_requests.json",
+        %{participation_requests: participation_requests} = opts
+      ) do
+    render_many(
+      participation_requests,
+      __MODULE__,
+      "participation_request.json",
+      Map.delete(opts, :participation_requests)
+    )
+  end
+
+  def render("participation_request.json", %{participation_request: participation_request} = opts) do
+    %{}
+  end
+end

lib/pleroma/web/router.ex

@@ -441,6 +441,9 @@ defmodule Pleroma.Web.Router do
 
       get("/backups", BackupController, :index)
       post("/backups", BackupController, :create)
+
+      post("/events", EventController, :create)
+      post("/events/:id/participate", EventController, :participate)
     end
 
     scope [] do

priv/static/schemas/litepub-0.1.jsonld

@@ -36,7 +36,16 @@
                 "@id": "as:alsoKnownAs",
                 "@type": "@id"
             },
-            "vcard": "http://www.w3.org/2006/vcard/ns#"
+            "vcard": "http://www.w3.org/2006/vcard/ns#",
+            "mz": "https://joinmobilizon.org/ns#",
+            "joinMode": {
+              "@id": "mz:joinMode",
+              "@type": "mz:joinModeType"
+            },
+            "joinModeType": {
+              "@id": "mz:joinModeType",
+              "@type": "rdfs:Class"
+            }
         }
     ]
 }