1 files changed, 89 insertions, 0 deletions
diff --git a/app/services/releases/base_service.rb b/app/services/releases/base_service.rb
new file mode 100644
index 00000000000..15d040287a3
--- /dev/null
+++ b/app/services/releases/base_service.rb
@@ -0,0 +1,89 @@
+# frozen_string_literal: true
+
+module Releases
+  class BaseService
+    include BaseServiceUtility
+    include Gitlab::Utils::StrongMemoize
+
+    attr_accessor :project, :current_user, :params
+
+    def initialize(project, user = nil, params = {})
+      @project, @current_user, @params = project, user, params.dup
+    end
+
+    delegate :repository, to: :project
+
+    def tag_name
+      params[:tag]
+    end
+
+    def ref
+      params[:ref]
+    end
+
+    def name
+      params[:name] || tag_name
+    end
+
+    def description
+      params[:description]
+    end
+
+    def released_at
+      params[:released_at]
+    end
+
+    def release
+      strong_memoize(:release) do
+        project.releases.find_by_tag(tag_name)
+      end
+    end
+
+    def existing_tag
+      strong_memoize(:existing_tag) do
+        repository.find_tag(tag_name)
+      end
+    end
+
+    def tag_exist?
+      existing_tag.present?
+    end
+
+    def repository
+      strong_memoize(:repository) do
+        project.repository
+      end
+    end
+
+    def milestones
+      return [] unless param_for_milestone_titles_provided?
+
+      strong_memoize(:milestones) do
+        MilestonesFinder.new(
+          project: project,
+          current_user: current_user,
+          project_ids: Array(project.id),
+          group_ids: Array(project_group_id),
+          state: 'all',
+          title: params[:milestones]
+        ).execute
+      end
+    end
+
+    def inexistent_milestones
+      return [] unless param_for_milestone_titles_provided?
+
+      existing_milestone_titles = milestones.map(&:title)
+      Array(params[:milestones]) - existing_milestone_titles
+    end
+
+    def param_for_milestone_titles_provided?
+      params.key?(:milestones)
+    end
+
+    # overridden in EE
+    def project_group_id; end
+  end
+end
+
+Releases::BaseService.prepend_if_ee('EE::Releases::BaseService')