Expose can_uninstall in cluster_status.json

Only prometheus can be uninstalled atm, the rest will be dealt with
later.

Presumption is that new application types will have uninstallation
implmemented at the same time.

18 files changed, 115 insertions, 1 deletions

diff --git a/app/models/clusters/applications/cert_manager.rb b/app/models/clusters/applications/cert_manager.rb
index ac0e7eb03bc..d6a7d1d2bdd 100644
--- a/app/models/clusters/applications/cert_manager.rb
+++ b/app/models/clusters/applications/cert_manager.rb
@@ -24,6 +24,12 @@ module Clusters
         'stable/cert-manager'
       end
 
+      # We will implement this in future MRs.
+      # Need to reverse postinstall step
+      def allowed_to_uninstall?
+        false
+      end
+
       def install_command
         Gitlab::Kubernetes::Helm::InstallCommand.new(
           name: 'certmanager',
diff --git a/app/models/clusters/applications/helm.rb b/app/models/clusters/applications/helm.rb
index 71aff00077d..a83d06c4b00 100644
--- a/app/models/clusters/applications/helm.rb
+++ b/app/models/clusters/applications/helm.rb
@@ -29,6 +29,13 @@ module Clusters
         self.status = 'installable' if cluster&.platform_kubernetes_active?
       end
 
+      # We will implement this in future MRs.
+      # Basically we need to check all other applications are not installed
+      # first.
+      def allowed_to_uninstall?
+        false
+      end
+
       def install_command
         Gitlab::Kubernetes::Helm::InitCommand.new(
           name: name,
diff --git a/app/models/clusters/applications/ingress.rb b/app/models/clusters/applications/ingress.rb
index 376d54aab2c..a1023f44049 100644
--- a/app/models/clusters/applications/ingress.rb
+++ b/app/models/clusters/applications/ingress.rb
@@ -35,6 +35,13 @@ module Clusters
         'stable/nginx-ingress'
       end
 
+      # We will implement this in future MRs.
+      # Basically we need to check all dependent applications are not installed
+      # first.
+      def allowed_to_uninstall?
+        false
+      end
+
       def install_command
         Gitlab::Kubernetes::Helm::InstallCommand.new(
           name: name,
diff --git a/app/models/clusters/applications/jupyter.rb b/app/models/clusters/applications/jupyter.rb
index f86ff3551a1..987c057ad6d 100644
--- a/app/models/clusters/applications/jupyter.rb
+++ b/app/models/clusters/applications/jupyter.rb
@@ -38,6 +38,12 @@ module Clusters
         content_values.to_yaml
       end
 
+      # Will be addressed in future MRs
+      # We need to investigate and document what will be permenantly deleted.
+      def allowed_to_uninstall?
+        false
+      end
+
       def install_command
         Gitlab::Kubernetes::Helm::InstallCommand.new(
           name: name,
diff --git a/app/models/clusters/applications/knative.rb b/app/models/clusters/applications/knative.rb
index 38cbc9ce8eb..9fbf5d8af04 100644
--- a/app/models/clusters/applications/knative.rb
+++ b/app/models/clusters/applications/knative.rb
@@ -51,6 +51,12 @@ module Clusters
         { "domain" => hostname }.to_yaml
       end
 
+      # Handled in a new issue:
+      # https://gitlab.com/gitlab-org/gitlab-ce/issues/59369
+      def allowed_to_uninstall?
+        false
+      end
+
       def install_command
         Gitlab::Kubernetes::Helm::InstallCommand.new(
           name: name,
diff --git a/app/models/clusters/applications/runner.rb b/app/models/clusters/applications/runner.rb
index 3ebf7a5cfba..af648db3708 100644
--- a/app/models/clusters/applications/runner.rb
+++ b/app/models/clusters/applications/runner.rb
@@ -29,6 +29,13 @@ module Clusters
         content_values.to_yaml
       end
 
+      # Need to investigate if pipelines run by this runner will stop upon the
+      # executor pod stopping
+      # I.e.run a pipeline, and uninstall runner while pipeline is running
+      def allowed_to_uninstall?
+        false
+      end
+
       def install_command
         Gitlab::Kubernetes::Helm::InstallCommand.new(
           name: name,
diff --git a/app/models/clusters/concerns/application_core.rb b/app/models/clusters/concerns/application_core.rb
index ee964fb7c93..4514498b84b 100644
--- a/app/models/clusters/concerns/application_core.rb
+++ b/app/models/clusters/concerns/application_core.rb
@@ -18,6 +18,16 @@ module Clusters
           self.status = 'installable' if cluster&.application_helm_available?
         end
 
+        def can_uninstall?
+          allowed_to_uninstall?
+        end
+
+        # All new applications should uninstall by default
+        # Override if there's dependencies that needs to be uninstalled first
+        def allowed_to_uninstall?
+          true
+        end
+
         def self.application_name
           self.to_s.demodulize.underscore
         end
diff --git a/app/serializers/cluster_application_entity.rb b/app/serializers/cluster_application_entity.rb
index a4a2c015c4e..2a916b13f52 100644
--- a/app/serializers/cluster_application_entity.rb
+++ b/app/serializers/cluster_application_entity.rb
@@ -10,4 +10,5 @@ class ClusterApplicationEntity < Grape::Entity
   expose :hostname, if: -> (e, _) { e.respond_to?(:hostname) }
   expose :email, if: -> (e, _) { e.respond_to?(:email) }
   expose :update_available?, as: :update_available, if: -> (e, _) { e.respond_to?(:update_available?) }
+  expose :can_uninstall?, as: :can_uninstall
 end
diff --git a/spec/fixtures/api/schemas/cluster_status.json b/spec/fixtures/api/schemas/cluster_status.json
index 9da07a0b253..695175689b9 100644
--- a/spec/fixtures/api/schemas/cluster_status.json
+++ b/spec/fixtures/api/schemas/cluster_status.json
@@ -36,7 +36,8 @@
         "external_hostname": { "type": ["string", "null"] },
         "hostname": { "type": ["string", "null"] },
         "email": { "type": ["string", "null"] },
-        "update_available": { "type": ["boolean", "null"] }
+        "update_available": { "type": ["boolean", "null"] },
+        "can_uninstall": { "type": "boolean" }
       },
       "required" : [ "name", "status" ]
     }
diff --git a/spec/models/clusters/applications/cert_manager_spec.rb b/spec/models/clusters/applications/cert_manager_spec.rb
index 5cd80edb3a1..8d853a04e33 100644
--- a/spec/models/clusters/applications/cert_manager_spec.rb
+++ b/spec/models/clusters/applications/cert_manager_spec.rb
@@ -10,6 +10,12 @@ describe Clusters::Applications::CertManager do
   include_examples 'cluster application version specs', :clusters_applications_cert_managers
   include_examples 'cluster application initial status specs'
 
+  describe '#can_uninstall?' do
+    subject { cert_manager.can_uninstall? }
+
+    it { is_expected.to be_falsey }
+  end
+
   describe '#install_command' do
     let(:cert_email) { 'admin@example.com' }
 
diff --git a/spec/models/clusters/applications/helm_spec.rb b/spec/models/clusters/applications/helm_spec.rb
index f177d493a2e..6ea6c110d62 100644
--- a/spec/models/clusters/applications/helm_spec.rb
+++ b/spec/models/clusters/applications/helm_spec.rb
@@ -18,6 +18,14 @@ describe Clusters::Applications::Helm do
     it { is_expected.to contain_exactly(installed_cluster, updated_cluster) }
   end
 
+  describe '#can_uninstall?' do
+    let(:helm) { create(:clusters_applications_helm) }
+
+    subject { helm.can_uninstall? }
+
+    it { is_expected.to be_falsey }
+  end
+
   describe '#issue_client_cert' do
     let(:application) { create(:clusters_applications_helm) }
     subject { application.issue_client_cert }
diff --git a/spec/models/clusters/applications/ingress_spec.rb b/spec/models/clusters/applications/ingress_spec.rb
index 113d29b5551..292ddabd2d8 100644
--- a/spec/models/clusters/applications/ingress_spec.rb
+++ b/spec/models/clusters/applications/ingress_spec.rb
@@ -18,6 +18,12 @@ describe Clusters::Applications::Ingress do
     allow(ClusterWaitForIngressIpAddressWorker).to receive(:perform_async)
   end
 
+  describe '#can_uninstall?' do
+    subject { ingress.can_uninstall? }
+
+    it { is_expected.to be_falsey }
+  end
+
   describe '#make_installed!' do
     before do
       application.make_installed!
diff --git a/spec/models/clusters/applications/jupyter_spec.rb b/spec/models/clusters/applications/jupyter_spec.rb
index 1a7363b64f9..fc9ebed863e 100644
--- a/spec/models/clusters/applications/jupyter_spec.rb
+++ b/spec/models/clusters/applications/jupyter_spec.rb
@@ -10,6 +10,15 @@ describe Clusters::Applications::Jupyter do
 
   it { is_expected.to belong_to(:oauth_application) }
 
+  describe '#can_uninstall?' do
+    let(:ingress) { create(:clusters_applications_ingress, :installed, external_hostname: 'localhost.localdomain') }
+    let(:jupyter) { create(:clusters_applications_jupyter, cluster: ingress.cluster) }
+
+    subject { jupyter.can_uninstall? }
+
+    it { is_expected.to be_falsey }
+  end
+
   describe '#set_initial_status' do
     before do
       jupyter.set_initial_status
diff --git a/spec/models/clusters/applications/knative_spec.rb b/spec/models/clusters/applications/knative_spec.rb
index 405b5ad691c..d5974f47190 100644
--- a/spec/models/clusters/applications/knative_spec.rb
+++ b/spec/models/clusters/applications/knative_spec.rb
@@ -39,6 +39,12 @@ describe Clusters::Applications::Knative do
     end
   end
 
+  describe '#can_uninstall?' do
+    subject { knative.can_uninstall? }
+
+    it { is_expected.to be_falsey }
+  end
+
   describe '#schedule_status_update with external_ip' do
     let(:application) { create(:clusters_applications_knative, :installed) }
 
diff --git a/spec/models/clusters/applications/prometheus_spec.rb b/spec/models/clusters/applications/prometheus_spec.rb
index e8ba9737c23..f390afe9b1f 100644
--- a/spec/models/clusters/applications/prometheus_spec.rb
+++ b/spec/models/clusters/applications/prometheus_spec.rb
@@ -29,6 +29,14 @@ describe Clusters::Applications::Prometheus do
     end
   end
 
+  describe '#can_uninstall?' do
+    let(:prometheus) { create(:clusters_applications_prometheus) }
+
+    subject { prometheus.can_uninstall? }
+
+    it { is_expected.to be_truthy }
+  end
+
   describe '#prometheus_client' do
     context 'cluster is nil' do
       it 'returns nil' do
diff --git a/spec/models/clusters/applications/runner_spec.rb b/spec/models/clusters/applications/runner_spec.rb
index b66acf13135..bdc0cb8ed86 100644
--- a/spec/models/clusters/applications/runner_spec.rb
+++ b/spec/models/clusters/applications/runner_spec.rb
@@ -13,6 +13,14 @@ describe Clusters::Applications::Runner do
 
   it { is_expected.to belong_to(:runner) }
 
+  describe '#can_uninstall?' do
+    let(:gitlab_runner) { create(:clusters_applications_runner, runner: ci_runner) }
+
+    subject { gitlab_runner.can_uninstall? }
+
+    it { is_expected.to be_falsey }
+  end
+
   describe '#install_command' do
     let(:kubeclient) { double('kubernetes client') }
     let(:gitlab_runner) { create(:clusters_applications_runner, runner: ci_runner) }
diff --git a/spec/serializers/cluster_application_entity_spec.rb b/spec/serializers/cluster_application_entity_spec.rb
index 7e151c3744e..f38a18fcf59 100644
--- a/spec/serializers/cluster_application_entity_spec.rb
+++ b/spec/serializers/cluster_application_entity_spec.rb
@@ -21,6 +21,10 @@ describe ClusterApplicationEntity do
       expect(subject[:status_reason]).to be_nil
     end
 
+    it 'has can_uninstall' do
+      expect(subject[:can_uninstall]).to be_falsey
+    end
+
     context 'non-helm application' do
       let(:application) { build(:clusters_applications_runner, version: '0.0.0') }
 
diff --git a/spec/support/shared_examples/models/cluster_application_core_shared_examples.rb b/spec/support/shared_examples/models/cluster_application_core_shared_examples.rb
index 1f76b981292..d6490a808ce 100644
--- a/spec/support/shared_examples/models/cluster_application_core_shared_examples.rb
+++ b/spec/support/shared_examples/models/cluster_application_core_shared_examples.rb
@@ -2,6 +2,14 @@ shared_examples 'cluster application core specs' do |application_name|
   it { is_expected.to belong_to(:cluster) }
   it { is_expected.to validate_presence_of(:cluster) }
 
+  describe '#can_uninstall?' do
+    it 'calls allowed_to_uninstall?' do
+      expect(subject).to receive(:allowed_to_uninstall?).and_return(true)
+
+      expect(subject.can_uninstall?).to be_truthy
+    end
+  end
+
   describe '#name' do
     it 'is .application_name' do
       expect(subject.name).to eq(described_class.application_name)