Раздел api Календари #22

src/handlers/handler_utils.erl

@@ -26,7 +26,9 @@
   calendar_to_json/1,
   subscription_to_json/1,
   trails_for_crud/4,
-  is_superadmin/1]).
+  is_superadmin/1,
+  pagination_headers/2
+]).
 
 -include("records.hrl").
 
@@ -118,6 +120,18 @@ parse_int_qs(undefined, Default) -> Default;
 parse_int_qs(Bin, Default) ->
   try binary_to_integer(Bin) catch _:_ -> Default end.
 
+-spec pagination_headers(map(), non_neg_integer()) -> map().
+pagination_headers(#{limit := Limit, offset := Offset}, Total) ->
+  NextOffset = Offset + Limit,
+  HasMore = NextOffset < Total,
+  #{
+    <<"x-total-count">> => integer_to_binary(Total),
+    <<"x-next-offset">> => case HasMore of
+                             true -> integer_to_binary(NextOffset);
+                             false -> <<"">>
+                           end
+  }.
+
 %% @doc Преобразует бинарный ISO8601 параметр в datetime().
 -spec parse_datetime_qs(binary() | undefined) -> calendar:datetime() | undefined.
 parse_datetime_qs(undefined) -> undefined;