1 files changed, 28 insertions, 6 deletions

diff --git a/lib/api/helpers/pagination_strategies.rb b/lib/api/helpers/pagination_strategies.rb
index 6bebb4bfeac..823891d6fe7 100644
--- a/lib/api/helpers/pagination_strategies.rb
+++ b/lib/api/helpers/pagination_strategies.rb
@@ -3,19 +3,24 @@
 module API
   module Helpers
     module PaginationStrategies
-      def paginate_with_strategies(relation)
-        paginator = paginator(relation)
+      def paginate_with_strategies(relation, request_scope)
+        paginator = paginator(relation, request_scope)
 
         yield(paginator.paginate(relation)).tap do |records, _|
           paginator.finalize(records)
         end
       end
 
-      def paginator(relation)
-        return Gitlab::Pagination::OffsetPagination.new(self) unless keyset_pagination_enabled?
+      def paginator(relation, request_scope = nil)
+        return keyset_paginator(relation) if keyset_pagination_enabled?
 
-        request_context = Gitlab::Pagination::Keyset::RequestContext.new(self)
+        offset_paginator(relation, request_scope)
+      end
+
+      private
 
+      def keyset_paginator(relation)
+        request_context = Gitlab::Pagination::Keyset::RequestContext.new(self)
         unless Gitlab::Pagination::Keyset.available?(request_context, relation)
           return error!('Keyset pagination is not yet available for this type of request', 405)
         end
@@ -23,11 +28,28 @@ module API
         Gitlab::Pagination::Keyset::Pager.new(request_context)
       end
 
-      private
+      def offset_paginator(relation, request_scope)
+        offset_limit = limit_for_scope(request_scope)
+        if Gitlab::Pagination::Keyset.available_for_type?(relation) && offset_limit_exceeded?(offset_limit)
+          return error!("Offset pagination has a maximum allowed offset of #{offset_limit} " \
+            "for requests that return objects of type #{relation.klass}. " \
+            "Remaining records can be retrieved using keyset pagination.", 405)
+        end
+
+        Gitlab::Pagination::OffsetPagination.new(self)
+      end
 
       def keyset_pagination_enabled?
         params[:pagination] == 'keyset'
       end
+
+      def limit_for_scope(scope)
+        (scope || Plan.default).actual_limits.offset_pagination_limit
+      end
+
+      def offset_limit_exceeded?(offset_limit)
+        offset_limit.positive? && params[:page] * params[:per_page] > offset_limit
+      end
     end
   end
 end