Fix installation of Knative under Helm 3

When we added Helm 3 support, I missed testing Knative
installation. We have now fixed the chart upstream, see
https://gitlab.com/gitlab-org/charts/knative/-/merge_requests/9
There are no other significant changes.

app/models/clusters/applications/cert_manager.rb

@@ -65,7 +65,7 @@ module Clusters
       end
 
       def retry_command(command)
-        "for i in $(seq 1 90); do #{command} && s=0 && break || s=$?; sleep 1s; echo \"Retrying ($i)...\"; done; (exit $s)"
+        Gitlab::Kubernetes::PodCmd.retry_command(command, times: 90)
       end
 
       def post_delete_script

app/models/clusters/applications/knative.rb

@@ -3,7 +3,7 @@
 module Clusters
   module Applications
     class Knative < ApplicationRecord
-      VERSION = '0.9.0'
+      VERSION = '0.10.0'
       REPOSITORY = 'https://charts.gitlab.io'
       METRICS_CONFIG = 'https://gitlab.com/gitlab-org/charts/knative/-/raw/v0.9.0/vendor/istio-metrics.yml'
       FETCH_IP_ADDRESS_DELAY = 30.seconds

changelogs/unreleased/update-knative-for-helm-3.yml

+---
+title: Fix installation of Knative under Helm 3
+merge_request: 49843
+author:
+type: fixed

lib/gitlab/kubernetes/kubectl_cmd.rb

@@ -17,7 +17,7 @@ module Gitlab
         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')
+          PodCmd.retry_command(api_resources(*api_resources_args) + " | xargs -r " + delete('--ignore-not-found', 'crd'))
         end
 
         def api_resources(*args)

lib/gitlab/kubernetes/pod_cmd.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module Kubernetes
+    # Miscellaneous commands that run in the helm-install-image pod, tuned to
+    # the idiosynchrasies of the default shell of helm-install-image
+    module PodCmd
+      class << self
+        def retry_command(command, times: 3)
+          "for i in $(seq 1 #{times.to_i}); do #{command} && s=0 && break || s=$?; sleep 1s; echo \"Retrying ($i)...\"; done; (exit $s)"
+        end
+      end
+    end
+  end
+end

spec/lib/gitlab/kubernetes/kubectl_cmd_spec.rb

@@ -56,9 +56,10 @@ RSpec.describe Gitlab::Kubernetes::KubectlCmd do
 
   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'
+      command = 'kubectl api-resources -o name --api-group foo | xargs -r kubectl delete --ignore-not-found crd'
+      command_with_retries = "for i in $(seq 1 3); do #{command} && s=0 && break || s=$?; sleep 1s; echo \"Retrying ($i)...\"; done; (exit $s)"
 
-      expect(described_class.delete_crds_from_group("foo")).to eq expected_command
+      expect(described_class.delete_crds_from_group("foo")).to eq command_with_retries
     end
   end
 end

spec/lib/gitlab/kubernetes/pod_cmd_spec.rb

+# frozen_string_literal: true
+
+require 'fast_spec_helper'
+
+RSpec.describe Gitlab::Kubernetes::PodCmd do
+  describe '.retry_command' do
+    it 'constructs string properly' do
+      command = 'my command'
+      command_with_retries = "for i in $(seq 1 3); do #{command} && s=0 && break || s=$?; sleep 1s; echo \"Retrying ($i)...\"; done; (exit $s)"
+
+      expect(described_class.retry_command(command)).to eq command_with_retries
+    end
+  end
+end

spec/models/clusters/applications/knative_spec.rb

@@ -150,7 +150,7 @@ RSpec.describe Clusters::Applications::Knative do
     subject { knative.install_command }
 
     it 'is initialized with latest version' do
-      expect(subject.version).to eq('0.9.0')
+      expect(subject.version).to eq('0.10.0')
     end
 
     it_behaves_like 'a command'
@@ -204,8 +204,8 @@ RSpec.describe Clusters::Applications::Knative do
 
       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 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")
+      expect(subject.postdelete[2]).to include("kubectl api-resources -o name --api-group #{api_groups[0]} | xargs -r kubectl delete --ignore-not-found crd")
+      expect(subject.postdelete[3]).to include("kubectl api-resources -o name --api-group #{api_groups[1]} | xargs -r kubectl delete --ignore-not-found crd")
     end
   end