1 files changed, 31 insertions, 0 deletions
diff --git a/app/services/branches/validate_new_service.rb b/app/services/branches/validate_new_service.rb
new file mode 100644
index 00000000000..e45183d160f
--- /dev/null
+++ b/app/services/branches/validate_new_service.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module Branches
+  class ValidateNewService < BaseService
+    def initialize(project)
+      @project = project
+    end
+
+    def execute(branch_name, force: false)
+      return error('Branch name is invalid') unless valid_name?(branch_name)
+
+      if branch_exist?(branch_name) && !force
+        return error('Branch already exists')
+      end
+
+      success
+    rescue Gitlab::Git::PreReceiveError => ex
+      error(ex.message)
+    end
+
+    private
+
+    def valid_name?(branch_name)
+      Gitlab::GitRefValidator.validate(branch_name)
+    end
+
+    def branch_exist?(branch_name)
+      project.repository.branch_exists?(branch_name)
+    end
+  end
+end