Only execute system hooks once when pushing tags

app/services/git/tag_push_service.rb

@@ -13,7 +13,6 @@ module Git
       EventCreateService.new.push(project, current_user, push_data)
       Ci::CreatePipelineService.new(project, current_user, push_data).execute(:push, pipeline_options)
 
-      SystemHooksService.new.execute_hooks(build_system_push_data, :tag_push_hooks)
       project.execute_hooks(push_data.dup, :tag_push_hooks)
       project.execute_services(push_data.dup, :tag_push_hooks)
 
@@ -50,17 +49,6 @@ module Git
         push_options: params[:push_options] || [])
     end
 
-    def build_system_push_data
-      Gitlab::DataBuilder::Push.build(
-        project,
-        current_user,
-        params[:oldrev],
-        params[:newrev],
-        params[:ref],
-        [],
-        '')
-    end
-
     def pipeline_options
       {} # to be overridden in EE
     end

changelogs/unreleased/52560-fix-duplicate-tag-system-hooks.yml

@@ -0,0 +1,5 @@
+---
+title: Only execute system hooks once when pushing tags
+merge_request: 26888
+author:
+type: fixed

spec/services/git/tag_push_service_spec.rb

@@ -31,6 +31,20 @@ describe Git::TagPushService do
     end
   end
 
+  describe 'System Hooks' do
+    let!(:push_data) { service.tap(&:execute).push_data }
+
+    it "executes system hooks after pushing a tag" do
+      expect_next_instance_of(SystemHooksService) do |system_hooks_service|
+        expect(system_hooks_service)
+          .to receive(:execute_hooks)
+          .with(push_data, :tag_push_hooks)
+      end
+
+      service.execute
+    end
+  end
+
   describe "Pipelines" do
     subject { service.execute }