Merge branch 'features/apc2s-pagination' into 'develop'

[akkoma] / lib / pleroma / web / controller_helper.ex

diff --git a/lib/pleroma/web/controller_helper.ex b/lib/pleroma/web/controller_helper.ex
index e3d7a465b8efbed81edf5dfec65c2428cf01692e..9414cf3f24377414bf55e6cc90e92cbc482c1bca 100644 (file)
--- a/lib/pleroma/web/controller_helper.ex
+++ b/lib/pleroma/web/controller_helper.ex
@@ -1,14 +1,22 @@
 # Pleroma: A lightweight social networking server
-# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
 # SPDX-License-Identifier: AGPL-3.0-only
 
 defmodule Pleroma.Web.ControllerHelper do
   use Pleroma.Web, :controller
 
-  # As in MastoAPI, per https://api.rubyonrails.org/classes/ActiveModel/Type/Boolean.html
+  alias Pleroma.Pagination
+
+  # As in Mastodon API, per https://api.rubyonrails.org/classes/ActiveModel/Type/Boolean.html
   @falsy_param_values [false, 0, "0", "f", "F", "false", "False", "FALSE", "off", "OFF"]
-  def truthy_param?(blank_value) when blank_value in [nil, ""], do: nil
-  def truthy_param?(value), do: value not in @falsy_param_values
+
+  def explicitly_falsy_param?(value), do: value in @falsy_param_values
+
+  # Note: `nil` and `""` are considered falsy values in Pleroma
+  def falsy_param?(value),
+    do: explicitly_falsy_param?(value) or value in [nil, ""]
+
+  def truthy_param?(value), do: not falsy_param?(value)
 
   def json_response(conn, status, json) do
     conn
@@ -34,43 +42,59 @@ defmodule Pleroma.Web.ControllerHelper do
 
   defp param_to_integer(_, default), do: default
 
-  def add_link_headers(conn, activities, extra_params \\ %{}) do
+  def add_link_headers(conn, activities, extra_params \\ %{})
+
+  def add_link_headers(%{assigns: %{skip_link_headers: true}} = conn, _activities, _extra_params),
+    do: conn
+
+  def add_link_headers(conn, activities, extra_params) do
+    case get_pagination_fields(conn, activities, extra_params) do
+      %{"next" => next_url, "prev" => prev_url} ->
+        put_resp_header(conn, "link", "<#{next_url}>; rel=\"next\", <#{prev_url}>; rel=\"prev\"")
+
+      _ ->
+        conn
+    end
+  end
+
+  def get_pagination_fields(conn, activities, extra_params \\ %{}) do
     case List.last(activities) do
       %{id: max_id} ->
         params =
           conn.params
           |> Map.drop(Map.keys(conn.path_params))
-          |> Map.drop(["since_id", "max_id", "min_id"])
           |> Map.merge(extra_params)
-
-        limit =
-          params
-          |> Map.get("limit", "20")
-          |> String.to_integer()
+          |> Map.drop(Pagination.page_keys() -- ["limit", "order"])
 
         min_id =
-          if length(activities) <= limit do
-            activities
-            |> List.first()
-            |> Map.get(:id)
-          else
-            activities
-            |> Enum.at(limit * -1)
-            |> Map.get(:id)
-          end
-
-        next_url = current_url(conn, Map.merge(params, %{max_id: max_id}))
-        prev_url = current_url(conn, Map.merge(params, %{min_id: min_id}))
-
-        put_resp_header(conn, "link", "<#{next_url}>; rel=\"next\", <#{prev_url}>; rel=\"prev\"")
+          activities
+          |> List.first()
+          |> Map.get(:id)
+
+        fields = %{
+          "next" => current_url(conn, Map.put(params, :max_id, max_id)),
+          "prev" => current_url(conn, Map.put(params, :min_id, min_id))
+        }
+
+        #  Generating an `id` without already present pagination keys would
+        # need a query-restriction with an `q.id >= ^id` or `q.id <= ^id`
+        # instead of the `q.id > ^min_id` and `q.id < ^max_id`.
+        #  This is because we only have ids present inside of the page, while
+        # `min_id`, `since_id` and `max_id` requires to know one outside of it.
+        if Map.take(conn.params, Pagination.page_keys() -- ["limit", "order"]) != [] do
+          Map.put(fields, "id", current_url(conn, conn.params))
+        else
+          fields
+        end
 
       _ ->
-        conn
+        %{}
     end
   end
 
-  def assign_account_by_id(%{params: %{"id" => id}} = conn, _) do
-    case Pleroma.User.get_cached_by_id(id) do
+  def assign_account_by_id(conn, _) do
+    # TODO: use `conn.params[:id]` only after moving to OpenAPI
+    case Pleroma.User.get_cached_by_id(conn.params[:id] || conn.params["id"]) do
       %Pleroma.User{} = account -> assign(conn, :account, account)
       nil -> Pleroma.Web.MastodonAPI.FallbackController.call(conn, {:error, :not_found}) |> halt()
     end
@@ -87,7 +111,16 @@ defmodule Pleroma.Web.ControllerHelper do
     render_error(conn, :not_implemented, "Can't display this activity")
   end
 
-  @spec put_in_if_exist(map(), atom() | String.t(), any) :: map()
-  def put_in_if_exist(map, _key, nil), do: map
-  def put_in_if_exist(map, key, value), do: put_in(map, key, value)
+  @doc """
+  Returns true if request specifies to include embedded relationships in account objects.
+  May only be used in selected account-related endpoints; has no effect for status- or
+    notification-related endpoints.
+  """
+  # Intended for PleromaFE: https://git.pleroma.social/pleroma/pleroma-fe/-/issues/838
+  def embed_relationships?(params) do
+    # To do once OpenAPI transition mess is over: just `truthy_param?(params[:with_relationships])`
+    params
+    |> Map.get(:with_relationships, params["with_relationships"])
+    |> truthy_param?()
+  end
 end