Improvements for Knative installation

Displays Knative domain field automatically after Helm is successfully
installed.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/56954

app/helpers/clusters_helper.rb

@@ -14,4 +14,10 @@ module ClustersHelper
       render 'clusters/clusters/gcp_signup_offer_banner'
     end
   end
+
+  def has_rbac_enabled?(cluster)
+    return cluster.platform_kubernetes_rbac? if cluster.platform_kubernetes
+
+    !cluster.provider.legacy_abac?
+  end
 end

app/views/clusters/clusters/show.html.haml

@@ -17,7 +17,7 @@
   install_knative_path: clusterable.install_applications_cluster_path(@cluster, :knative),
   update_knative_path: clusterable.update_applications_cluster_path(@cluster, :knative),
   toggle_status: @cluster.enabled? ? 'true': 'false',
-  has_rbac: @cluster.platform_kubernetes_rbac? ? 'true': 'false',
+  has_rbac: has_rbac_enabled?(@cluster) ? 'true': 'false',
   cluster_type: @cluster.cluster_type,
   cluster_status: @cluster.status_name,
   cluster_status_reason: @cluster.status_reason,

changelogs/unreleased/56954-improve-knative-after-installing-tiller.yml

+---
+title: Improve the Knative installation on Clusters
+merge_request: 26339
+author:
+type: added

spec/factories/clusters/providers/gcp.rb

@@ -28,5 +28,9 @@ FactoryBot.define do
         gcp.make_errored('Something wrong')
       end
     end
+
+    trait :abac_enabled do
+      legacy_abac true
+    end
   end
 end

spec/helpers/clusters_helper_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe ClustersHelper do
+  describe '#has_rbac_enabled?' do
+    context 'when kubernetes platform has been created' do
+      let(:platform_kubernetes) { build_stubbed(:cluster_platform_kubernetes) }
+      let(:cluster) { build_stubbed(:cluster, :provided_by_gcp, platform_kubernetes: platform_kubernetes) }
+
+      it 'returns kubernetes platform value' do
+        expect(helper.has_rbac_enabled?(cluster)).to be_truthy
+      end
+    end
+
+    context 'when kubernetes platform has not been created yet' do
+      let(:cluster) { build_stubbed(:cluster, :providing_by_gcp) }
+
+      it 'delegates to cluster provider' do
+        expect(helper.has_rbac_enabled?(cluster)).to be_truthy
+      end
+
+      context 'when ABAC cluster is created' do
+        let(:provider) { build_stubbed(:cluster_provider_gcp, :abac_enabled) }
+        let(:cluster) { build_stubbed(:cluster, :providing_by_gcp, provider_gcp: provider) }
+
+        it 'delegates to cluster provider' do
+          expect(helper.has_rbac_enabled?(cluster)).to be_falsy
+        end
+      end
+    end
+  end
+end