1 files changed, 90 insertions, 0 deletions
diff --git a/spec/services/clusters/integrations/create_service_spec.rb b/spec/services/clusters/integrations/create_service_spec.rb
new file mode 100644
index 00000000000..cfc0943b6ad
--- /dev/null
+++ b/spec/services/clusters/integrations/create_service_spec.rb
@@ -0,0 +1,90 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Clusters::Integrations::CreateService, '#execute' do
+  let_it_be(:project) { create(:project) }
+  let_it_be_with_reload(:cluster) { create(:cluster, :provided_by_gcp, projects: [project]) }
+
+  let(:params) do
+    { application_type: 'prometheus', enabled: true }
+  end
+
+  let(:service) do
+    described_class.new(container: project, cluster: cluster, current_user: project.owner, params: params)
+  end
+
+  it 'creates a new Prometheus instance' do
+    expect(service.execute).to be_success
+
+    expect(cluster.integration_prometheus).to be_present
+    expect(cluster.integration_prometheus).to be_persisted
+    expect(cluster.integration_prometheus).to be_enabled
+  end
+
+  context 'enabled param is false' do
+    let(:params) do
+      { application_type: 'prometheus', enabled: false }
+    end
+
+    it 'creates a new uninstalled Prometheus instance' do
+      expect(service.execute).to be_success
+
+      expect(cluster.integration_prometheus).to be_present
+      expect(cluster.integration_prometheus).to be_persisted
+      expect(cluster.integration_prometheus).not_to be_enabled
+    end
+  end
+
+  context 'unauthorized user' do
+    let(:service) do
+      unauthorized_user = create(:user)
+
+      described_class.new(container: project, cluster: cluster, current_user: unauthorized_user, params: params)
+    end
+
+    it 'does not create a new Prometheus instance' do
+      expect(service.execute).to be_error
+
+      expect(cluster.integration_prometheus).to be_nil
+    end
+  end
+
+  context 'prometheus record exists' do
+    before do
+      create(:clusters_integrations_prometheus, cluster: cluster)
+    end
+
+    it 'updates the Prometheus instance' do
+      expect(service.execute).to be_success
+
+      expect(cluster.integration_prometheus).to be_present
+      expect(cluster.integration_prometheus).to be_persisted
+      expect(cluster.integration_prometheus).to be_enabled
+    end
+
+    context 'enabled param is false' do
+      let(:params) do
+        { application_type: 'prometheus', enabled: false }
+      end
+
+      it 'updates the Prometheus instance as uninstalled' do
+        expect(service.execute).to be_success
+
+        expect(cluster.integration_prometheus).to be_present
+        expect(cluster.integration_prometheus).to be_persisted
+        expect(cluster.integration_prometheus).not_to be_enabled
+      end
+    end
+  end
+
+  context 'for an un-supported application type' do
+    let(:params) do
+      { application_type: 'something_else', enabled: true }
+    end
+
+    it 'errors' do
+      expect { service.execute}.to raise_error(ArgumentError)
+    end
+  end
+end