1 files changed, 98 insertions, 0 deletions
diff --git a/lib/api/milestone_responses.rb b/lib/api/milestone_responses.rb
new file mode 100644
index 00000000000..ef09d9505d2
--- /dev/null
+++ b/lib/api/milestone_responses.rb
@@ -0,0 +1,98 @@
+module API
+  module MilestoneResponses
+    extend ActiveSupport::Concern
+
+    included do
+      helpers do
+        params :optional_params do
+          optional :description, type: String, desc: 'The description of the milestone'
+          optional :due_date, type: String, desc: 'The due date of the milestone. The ISO 8601 date format (%Y-%m-%d)'
+          optional :start_date, type: String, desc: 'The start date of the milestone. The ISO 8601 date format (%Y-%m-%d)'
+        end
+
+        params :list_params do
+          optional :state, type: String, values: %w[active closed all], default: 'all',
+                           desc: 'Return "active", "closed", or "all" milestones'
+          optional :iids, type: Array[Integer], desc: 'The IIDs of the milestones'
+          optional :search, type: String, desc: 'The search criteria for the title or description of the milestone'
+          use :pagination
+        end
+
+        params :update_params do
+          requires :milestone_id, type: Integer, desc: 'The milestone ID number'
+          optional :title, type: String, desc: 'The title of the milestone'
+          optional :state_event, type: String, values: %w[close activate],
+                                 desc: 'The state event of the milestone '
+          use :optional_params
+          at_least_one_of :title, :description, :due_date, :state_event
+        end
+
+        def list_milestones_for(parent)
+          milestones = parent.milestones
+          milestones = Milestone.filter_by_state(milestones, params[:state])
+          milestones = filter_by_iid(milestones, params[:iids]) if params[:iids].present?
+          milestones = filter_by_search(milestones, params[:search]) if params[:search]
+
+          present paginate(milestones), with: Entities::Milestone
+        end
+
+        def get_milestone_for(parent)
+          milestone = parent.milestones.find(params[:milestone_id])
+          present milestone, with: Entities::Milestone
+        end
+
+        def create_milestone_for(parent)
+          milestone = ::Milestones::CreateService.new(parent, current_user, declared_params).execute
+
+          if milestone.valid?
+            present milestone, with: Entities::Milestone
+          else
+            render_api_error!("Failed to create milestone #{milestone.errors.messages}", 400)
+          end
+        end
+
+        def update_milestone_for(parent)
+          milestone = parent.milestones.find(params.delete(:milestone_id))
+
+          milestone_params = declared_params(include_missing: false)
+          milestone = ::Milestones::UpdateService.new(parent, current_user, milestone_params).execute(milestone)
+
+          if milestone.valid?
+            present milestone, with: Entities::Milestone
+          else
+            render_api_error!("Failed to update milestone #{milestone.errors.messages}", 400)
+          end
+        end
+
+        def milestone_issuables_for(parent, type)
+          milestone = parent.milestones.find(params[:milestone_id])
+
+          finder_klass, entity = get_finder_and_entity(type)
+
+          params = build_finder_params(milestone, parent)
+
+          issuables = finder_klass.new(current_user, params).execute
+          present paginate(issuables), with: entity, current_user: current_user
+        end
+
+        def build_finder_params(milestone, parent)
+          finder_params = { milestone_title: milestone.title, sort: 'label_priority' }
+
+          if parent.is_a?(Group)
+            finder_params.merge(group_id: parent.id)
+          else
+            finder_params.merge(project_id: parent.id)
+          end
+        end
+
+        def get_finder_and_entity(type)
+          if type == :issue
+            [IssuesFinder, Entities::IssueBasic]
+          else
+            [MergeRequestsFinder, Entities::MergeRequestBasic]
+          end
+        end
+      end
+    end
+  end
+end