Remove Knative CRDs by group name instead of individually

- Tracks likst of api_groups instead of CRDs (much smaller)
- Adds kubectl command to fetch api resources by api group
- Adds kubectl command to delete api resources by api group
- Adds/Updates specs

app/models/clusters/applications/knative.rb

@@ -7,7 +7,7 @@ module Clusters
       REPOSITORY = 'https://storage.googleapis.com/triggermesh-charts'
       METRICS_CONFIG = 'https://storage.googleapis.com/triggermesh-charts/istio-metrics.yaml'
       FETCH_IP_ADDRESS_DELAY = 30.seconds
-      API_RESOURCES_PATH = 'config/knative/api_resources.yml'
+      API_GROUPS_PATH = 'config/knative/api_groups.yml'
 
       self.table_name = 'clusters_applications_knative'
 
@@ -109,15 +109,15 @@ module Clusters
       end
 
       def delete_knative_and_istio_crds
-        api_resources.map do |crd|
-          Gitlab::Kubernetes::KubectlCmd.delete("--ignore-not-found", "crd", "#{crd}")
+        api_groups.map do |group|
+          Gitlab::Kubernetes::KubectlCmd.delete_crds_from_group(group)
         end
       end
 
       # returns an array of CRDs to be postdelete since helm does not
       # manage the CRDs it creates.
-      def api_resources
-        @api_resources ||= YAML.safe_load(File.read(Rails.root.join(API_RESOURCES_PATH)))
+      def api_groups
+        @api_groups ||= YAML.safe_load(File.read(Rails.root.join(API_GROUPS_PATH)))
       end
 
       def install_knative_metrics

config/knative/api_groups.yml

+---
+
+- networking.istio.io
+- rbac.istio.io
+- authentication.istio.io
+- config.istio.io
+
+- networking.internal.knative.dev
+- serving.knative.dev
+- caching.internal.knative.dev
+- autoscaling.internal.knative.dev
\ No newline at end of file

config/knative/api_resources.yml

----
-
-- meshpolicies.authentication.istio.io
-- policies.authentication.istio.io
-- adapters.config.istio.io
-- apikeys.config.istio.io
-- attributemanifests.config.istio.io
-- authorizations.config.istio.io
-- bypasses.config.istio.io
-- podautoscalers.autoscaling.internal.knative.dev
-- builds.build.knative.dev
-- buildtemplates.build.knative.dev
-- clusterbuildtemplates.build.knative.dev
-- images.caching.internal.knative.dev
-- certificates.networking.internal.knative.dev
-- clusteringresses.networking.internal.knative.dev
-- serverlessservices.networking.internal.knative.dev
-- configurations.serving.knative.dev
-- revisions.serving.knative.dev
-- routes.serving.knative.dev
-- services.serving.knative.dev
-- checknothings.config.istio.io
-- circonuses.config.istio.io
-- deniers.config.istio.io
-- edges.config.istio.io
-- fluentds.config.istio.io
-- handlers.config.istio.io
-- httpapispecbindings.config.istio.io
-- httpapispecs.config.istio.io
-- instances.config.istio.io
-- kubernetesenvs.config.istio.io
-- kuberneteses.config.istio.io
-- listcheckers.config.istio.io
-- listentries.config.istio.io
-- logentries.config.istio.io
-- memquotas.config.istio.io
-- metrics.config.istio.io
-- noops.config.istio.io
-- opas.config.istio.io
-- prometheuses.config.istio.io
-- quotas.config.istio.io
-- quotaspecbindings.config.istio.io
-- quotaspecs.config.istio.io
-- rbacs.config.istio.io
-- redisquotas.config.istio.io
-- reportnothings.config.istio.io
-- rules.config.istio.io
-- servicecontrolreports.config.istio.io
-- servicecontrols.config.istio.io
-- signalfxs.config.istio.io
-- solarwindses.config.istio.io
-- stackdrivers.config.istio.io
-- statsds.config.istio.io
-- stdios.config.istio.io
-- templates.config.istio.io
-- tracespans.config.istio.io
-- destinationrules.networking.istio.io
-- envoyfilters.networking.istio.io
-- gateways.networking.istio.io
-- serviceentries.networking.istio.io
-- virtualservices.networking.istio.io
-- rbacconfigs.rbac.istio.io
-- servicerolebindings.rbac.istio.io
-- serviceroles.rbac.istio.io
-- cloudwatches.config.istio.io
-- clusterrbacconfigs.rbac.istio.io
-- dogstatsds.config.istio.io
-- ingresses.networking.internal.knative.dev
-- sidecars.networking.istio.io
-- zipkins.config.istio.io

lib/gitlab/kubernetes/kubectl_cmd.rb

@@ -13,6 +13,16 @@ module Gitlab
 
           %w(kubectl apply -f).concat([filename], args).shelljoin
         end
+
+        def delete_crds_from_group(group)
+          api_resources_args = %w(-o name --api-group).push(group)
+
+          api_resources(*api_resources_args) + " | xargs " + delete('--ignore-not-found', 'crd')
+        end
+
+        def api_resources(*args)
+          %w(kubectl api-resources).concat(args).shelljoin
+        end
       end
     end
   end

spec/lib/gitlab/kubernetes/kubectl_cmd_spec.rb

@@ -45,4 +45,20 @@ describe Gitlab::Kubernetes::KubectlCmd do
       end
     end
   end
+
+  describe '.api_resources' do
+    it 'constructs string properly' do
+      expected_command = 'kubectl api-resources -o name --api-group foo'
+
+      expect(described_class.api_resources("-o", "name", "--api-group", "foo")).to eq expected_command
+    end
+  end
+
+  describe '.delete_crds_from_group' do
+    it 'constructs string properly' do
+      expected_command = 'kubectl api-resources -o name --api-group foo | xargs kubectl delete --ignore-not-found crd'
+
+      expect(described_class.delete_crds_from_group("foo")).to eq expected_command
+    end
+  end
 end

spec/models/clusters/applications/knative_spec.rb

@@ -161,18 +161,19 @@ describe Clusters::Applications::Knative do
     end
 
     it "initializes command with all necessary postdelete script" do
-      api_resources = YAML.safe_load(File.read(Rails.root.join(Clusters::Applications::Knative::API_RESOURCES_PATH)))
+      api_groups = YAML.safe_load(File.read(Rails.root.join(Clusters::Applications::Knative::API_GROUPS_PATH)))
 
       remove_knative_istio_leftovers_script = [
         "kubectl delete --ignore-not-found ns knative-serving",
         "kubectl delete --ignore-not-found ns knative-build"
       ]
 
-      full_delete_commands_size = api_resources.size + remove_knative_istio_leftovers_script.size
+      full_delete_commands_size = api_groups.size + remove_knative_istio_leftovers_script.size
 
       expect(subject.postdelete).to include(*remove_knative_istio_leftovers_script)
       expect(subject.postdelete.size).to eq(full_delete_commands_size)
-      expect(subject.postdelete[2]).to eq("kubectl delete --ignore-not-found crd #{api_resources[0]}")
+      expect(subject.postdelete[2]).to eq("kubectl api-resources -o name --api-group #{api_groups[0]} | xargs kubectl delete --ignore-not-found crd")
+      expect(subject.postdelete[3]).to eq("kubectl api-resources -o name --api-group #{api_groups[1]} | xargs kubectl delete --ignore-not-found crd")
     end
   end