Chats: Introduce /api/v2/pleroma/chats which implements pagination

Also removes incorrect claim that /api/v1/pleroma/chats supports
pagination and deprecates it.

Closes #2140

3 files changed, 51 insertions, 10 deletions

diff --git a/lib/pleroma/web/api_spec/operations/chat_operation.ex b/lib/pleroma/web/api_spec/operations/chat_operation.ex
index b49700172..23cb66392 100644
--- a/lib/pleroma/web/api_spec/operations/chat_operation.ex
+++ b/lib/pleroma/web/api_spec/operations/chat_operation.ex
@@ -131,10 +131,32 @@ defmodule Pleroma.Web.ApiSpec.ChatOperation do
   def index_operation do
     %Operation{
       tags: ["Chats"],
-      summary: "Retrieve list of chats",
+      summary: "Retrieve list of chats (unpaginated)",
+      deprecated: true,
+      description:
+        "Deprecated due to no support for pagination. Using [/api/v2/pleroma/chats](#operation/ChatController.index2) instead is recommended.",
       operationId: "ChatController.index",
       parameters: [
         Operation.parameter(:with_muted, :query, BooleanLike, "Include chats from muted users")
+      ],
+      responses: %{
+        200 => Operation.response("The chats of the user", "application/json", chats_response())
+      },
+      security: [
+        %{
+          "oAuth" => ["read:chats"]
+        }
+      ]
+    }
+  end
+
+  def index2_operation do
+    %Operation{
+      tags: ["Chats"],
+      summary: "Retrieve list of chats",
+      operationId: "ChatController.index2",
+      parameters: [
+        Operation.parameter(:with_muted, :query, BooleanLike, "Include chats from muted users")
         | pagination_params()
       ],
       responses: %{
diff --git a/lib/pleroma/web/pleroma_api/controllers/chat_controller.ex b/lib/pleroma/web/pleroma_api/controllers/chat_controller.ex
index f3cd1fbf6..4adc685fe 100644
--- a/lib/pleroma/web/pleroma_api/controllers/chat_controller.ex
+++ b/lib/pleroma/web/pleroma_api/controllers/chat_controller.ex
@@ -35,7 +35,7 @@ defmodule Pleroma.Web.PleromaAPI.ChatController do
 
   plug(
     OAuthScopesPlug,
-    %{scopes: ["read:chats"]} when action in [:messages, :index, :show]
+    %{scopes: ["read:chats"]} when action in [:messages, :index, :index2, :show]
   )
 
   plug(OpenApiSpex.Plug.CastAndValidate, render_error: Pleroma.Web.ApiSpec.RenderError)
@@ -138,20 +138,32 @@ defmodule Pleroma.Web.PleromaAPI.ChatController do
     end
   end
 
-  def index(%{assigns: %{user: %{id: user_id} = user}} = conn, params) do
-    exclude_users =
-      User.cached_blocked_users_ap_ids(user) ++
-        if params[:with_muted], do: [], else: User.cached_muted_users_ap_ids(user)
-
+  def index(%{assigns: %{user: user}} = conn, params) do
     chats =
-      user_id
-      |> Chat.for_user_query()
-      |> where([c], c.recipient not in ^exclude_users)
+      index_query(user, params)
       |> Repo.all()
 
     render(conn, "index.json", chats: chats)
   end
 
+  def index2(%{assigns: %{user: user}} = conn, params) do
+    chats =
+      index_query(user, params)
+      |> Pagination.fetch_paginated(params)
+
+    render(conn, "index.json", chats: chats)
+  end
+
+  defp index_query(%{id: user_id} = user, params) do
+    exclude_users =
+      User.cached_blocked_users_ap_ids(user) ++
+        if params[:with_muted], do: [], else: User.cached_muted_users_ap_ids(user)
+
+    user_id
+    |> Chat.for_user_query()
+    |> where([c], c.recipient not in ^exclude_users)
+  end
+
   def create(%{assigns: %{user: user}} = conn, %{id: id}) do
     with %User{ap_id: recipient} <- User.get_cached_by_id(id),
          {:ok, %Chat{} = chat} <- Chat.get_or_create(user.id, recipient) do
diff --git a/lib/pleroma/web/router.ex b/lib/pleroma/web/router.ex
index 2105d7e9e..1a27bc63d 100644
--- a/lib/pleroma/web/router.ex
+++ b/lib/pleroma/web/router.ex
@@ -411,6 +411,13 @@ defmodule Pleroma.Web.Router do
     get("/federation_status", InstancesController, :show)
   end
 
+  scope "/api/v2/pleroma", Pleroma.Web.PleromaAPI do
+    scope [] do
+      pipe_through(:authenticated_api)
+      get("/chats", ChatController, :index2)
+    end
+  end
+
   scope "/api/v1", Pleroma.Web.MastodonAPI do
     pipe_through(:authenticated_api)