diff --git a/lib/api/helpers.rb b/lib/api/helpers.rb
index 3c9d7b1aaef..6998b6dc039 100644
--- a/lib/api/helpers.rb
+++ b/lib/api/helpers.rb
@@ -23,6 +23,11 @@ module API
       warden.try(:authenticate) if %w[GET HEAD].include?(env['REQUEST_METHOD'])
     end
 
+    def declared_params(options = {})
+      options = { include_parent_namespaces: false }.merge(options)
+      declared(params, options).to_h.symbolize_keys
+    end
+
     def find_user_by_private_token
       token = private_token
       return nil unless token.present?
diff --git a/lib/api/milestones.rb b/lib/api/milestones.rb
index 8984cf8cdcd..ba4a84275bc 100644
--- a/lib/api/milestones.rb
+++ b/lib/api/milestones.rb
@@ -62,9 +62,8 @@ module API
       end
       post ":id/milestones" do
         authorize! :admin_milestone, user_project
-        milestone_params = declared(params, include_parent_namespaces: false)
 
-        milestone = ::Milestones::CreateService.new(user_project, current_user, milestone_params).execute
+        milestone = ::Milestones::CreateService.new(user_project, current_user, declared_params).execute
 
         if milestone.valid?
           present milestone, with: Entities::Milestone
@@ -86,9 +85,9 @@ module API
       end
       put ":id/milestones/:milestone_id" do
         authorize! :admin_milestone, user_project
-        milestone_params = declared(params, include_parent_namespaces: false, include_missing: false)
+        milestone = user_project.milestones.find(params.delete(:milestone_id))
 
-        milestone = user_project.milestones.find(milestone_params.delete(:milestone_id))
+        milestone_params = declared_params(include_missing: false)
         milestone = ::Milestones::UpdateService.new(user_project, current_user, milestone_params).execute(milestone)
 
         if milestone.valid?
diff --git a/lib/api/runners.rb b/lib/api/runners.rb
index 84c19c432b0..b145cce7e3e 100644
--- a/lib/api/runners.rb
+++ b/lib/api/runners.rb
@@ -57,9 +57,7 @@ module API
         runner = get_runner(params.delete(:id))
         authenticate_update_runner!(runner)
 
-        runner_params = declared(params, include_missing: false)
-
-        if runner.update(runner_params)
+        if runner.update(declared_params(include_missing: false))
           present runner, with: Entities::RunnerDetails, current_user: current_user
         else
           render_validation_error!(runner)