Expose app version to frontend

app/serializers/cluster_application_entity.rb

@@ -4,6 +4,7 @@ class ClusterApplicationEntity < Grape::Entity
   expose :name
   expose :status_name, as: :status
   expose :status_reason
+  expose :version
   expose :external_ip, if: -> (e, _) { e.respond_to?(:external_ip) }
   expose :hostname, if: -> (e, _) { e.respond_to?(:hostname) }
   expose :email, if: -> (e, _) { e.respond_to?(:email) }

changelogs/unreleased/cluster_status_for_ugprading.yml

+---
+title: Expose version for each application in cluster_status JSON endpoint
+merge_request: 24791
+author:
+type: other

spec/fixtures/api/schemas/cluster_status.json

@@ -30,6 +30,7 @@
             ]
           }
         },
+        "version": { "type": "string" },
         "status_reason": { "type": ["string", "null"] },
         "external_ip": { "type": ["string", "null"] },
         "hostname": { "type": ["string", "null"] },

spec/serializers/cluster_application_entity_spec.rb

@@ -2,7 +2,7 @@ require 'spec_helper'
 
 describe ClusterApplicationEntity do
   describe '#as_json' do
-    let(:application) { build(:clusters_applications_helm) }
+    let(:application) { build(:clusters_applications_helm, version: '0.1.1') }
     subject { described_class.new(application).as_json }
 
     it 'has name' do
@@ -13,6 +13,10 @@ describe ClusterApplicationEntity do
       expect(subject[:status]).to eq(:not_installable)
     end
 
+    it 'has version' do
+      expect(subject[:version]).to eq('0.1.1')
+    end
+
     it 'has no status_reason' do
       expect(subject[:status_reason]).to be_nil
     end