diff --git a/app/models/gcp/cluster.rb b/app/models/gcp/cluster.rb
index fceda191880..0e8b920741d 100644
--- a/app/models/gcp/cluster.rb
+++ b/app/models/gcp/cluster.rb
@@ -97,7 +97,7 @@ module Gcp
     end
 
     def api_url
-      'https://' + endpoint
+      'https://' + endpoint if endpoint
     end
 
     def restrict_modification
diff --git a/app/services/ci/integrate_cluster_service.rb b/app/services/ci/integrate_cluster_service.rb
index 857bca3f953..d123ce8d26b 100644
--- a/app/services/ci/integrate_cluster_service.rb
+++ b/app/services/ci/integrate_cluster_service.rb
@@ -20,7 +20,7 @@ module Ci
           token: token)
       end
     rescue ActiveRecord::RecordInvalid => e
-      cluster.error!("Failed to integrate cluster into kubernetes_service: #{e.message}")
+      cluster.make_errored!("Failed to integrate cluster into kubernetes_service: #{e.message}")
     end
   end
 end
diff --git a/spec/factories/gcp/cluster.rb b/spec/factories/gcp/cluster.rb
index 2f98d024084..630e40da888 100644
--- a/spec/factories/gcp/cluster.rb
+++ b/spec/factories/gcp/cluster.rb
@@ -7,9 +7,18 @@ FactoryGirl.define do
     gcp_cluster_name 'test-cluster'
     gcp_cluster_zone 'us-central1-a'
     gcp_cluster_size 1
+    gcp_machine_type 'n1-standard-4'
 
     trait :with_kubernetes_service do
-      service :kubernetes_service
+      after(:create) do |cluster, evaluator|
+        create(:kubernetes_service, project: cluster.project).tap do |service|
+          cluster.update(service: service)
+        end
+      end
+    end
+
+    trait :custom_project_namespace do
+      project_namespace 'sample-app'
     end
 
     trait :created_on_gke do
diff --git a/spec/services/ci/integrate_cluster_service_spec.rb b/spec/services/ci/integrate_cluster_service_spec.rb
index 7a8c80ca4e7..3a79c205bd1 100644
--- a/spec/services/ci/integrate_cluster_service_spec.rb
+++ b/spec/services/ci/integrate_cluster_service_spec.rb
@@ -2,15 +2,40 @@ require 'spec_helper'
 
 describe Ci::IntegrateClusterService do
   describe '#execute' do
+    let(:cluster) { create(:gcp_cluster, :custom_project_namespace) }
+    let(:endpoint) { '123.123.123.123' }
+    let(:ca_cert) { 'ca_cert_xxx' }
+    let(:token) { 'token_xxx' }
+    let(:username) { 'username_xxx' }
+    let(:password) { 'password_xxx' }
+
+    before do
+      described_class
+        .new.execute(cluster, endpoint, ca_cert, token, username, password)
+
+      cluster.reload
+    end
+
     context 'when correct params' do
       it 'creates a cluster object' do
-        
+        expect(cluster.endpoint).to eq(endpoint)
+        expect(cluster.ca_cert).to eq(ca_cert)
+        expect(cluster.kubernetes_token).to eq(token)
+        expect(cluster.username).to eq(username)
+        expect(cluster.password).to eq(password)
+        expect(cluster.service.active).to be_truthy
+        expect(cluster.service.api_url).to eq(cluster.api_url)
+        expect(cluster.service.ca_pem).to eq(ca_cert)
+        expect(cluster.service.namespace).to eq(cluster.project_namespace)
+        expect(cluster.service.token).to eq(token)
       end
     end
 
     context 'when invalid params' do
-      it 'returns a cluster object with error' do
+      let(:endpoint) { nil }
 
+      it 'sets an error to cluster object' do
+        expect(cluster).to be_errored
       end
     end
   end
diff --git a/spec/services/ci/provision_cluster_service_spec.rb b/spec/services/ci/provision_cluster_service_spec.rb
index d1595c8917d..5ce5c788314 100644
--- a/spec/services/ci/provision_cluster_service_spec.rb
+++ b/spec/services/ci/provision_cluster_service_spec.rb
@@ -2,16 +2,84 @@ require 'spec_helper'
 
 describe Ci::ProvisionClusterService do
   describe '#execute' do
-    context 'when correct params' do
-      it 'creates a cluster on gke' do
-        
+    let(:cluster) { create(:gcp_cluster) }
+    let(:operation) { spy }
+
+    shared_examples 'error' do
+      it 'sets an error to cluster object' do
+        described_class.new.execute(cluster)
+
+        expect(cluster.reload).to be_errored
       end
     end
 
-    context 'when invalid params' do
-      it 'returns a cluster object with error' do
-
+    context 'when suceeded to request provision' do
+      before do
+        allow_any_instance_of(GoogleApi::CloudPlatform::Client)
+          .to receive(:projects_zones_clusters_create).and_return(operation)
       end
+
+      context 'when operation status is RUNNING' do
+        before do
+          allow(operation).to receive(:status).and_return('RUNNING')
+        end
+
+        context 'when suceeded to parse gcp operation id' do
+          before do
+            allow_any_instance_of(GoogleApi::CloudPlatform::Client)
+              .to receive(:parse_operation_id).and_return('operation-123')
+          end
+
+          context 'when cluster status is scheduled' do
+            before do
+              allow_any_instance_of(GoogleApi::CloudPlatform::Client)
+                .to receive(:parse_operation_id).and_return('operation-123')
+            end
+
+            it 'schedules a worker for status minitoring' do
+              expect(WaitForClusterCreationWorker).to receive(:perform_in)
+
+              described_class.new.execute(cluster)
+            end
+          end
+
+          context 'when cluster status is creating' do
+            before do
+              cluster.make_creating!
+            end
+
+            it_behaves_like 'error'
+          end
+        end
+
+        context 'when failed to parse gcp operation id' do
+          before do
+            allow_any_instance_of(GoogleApi::CloudPlatform::Client)
+              .to receive(:parse_operation_id).and_return(nil)
+          end
+
+          it_behaves_like 'error'
+        end
+      end
+
+      context 'when operation status is others' do
+        before do
+          allow(operation).to receive(:status).and_return('others')
+        end
+
+        it_behaves_like 'error'
+      end
+    end
+
+    context 'when failed to request provision' do
+      let(:error) { Google::Apis::ServerError.new('a') }
+
+      before do
+        allow_any_instance_of(GoogleApi::CloudPlatform::Client)
+          .to receive(:projects_zones_clusters_create).and_raise(error)
+      end
+
+      it_behaves_like 'error'
     end
   end
 end
diff --git a/spec/services/ci/update_cluster_service_spec.rb b/spec/services/ci/update_cluster_service_spec.rb
index afe3d418a8e..a289385b88f 100644
--- a/spec/services/ci/update_cluster_service_spec.rb
+++ b/spec/services/ci/update_cluster_service_spec.rb
@@ -2,15 +2,35 @@ require 'spec_helper'
 
 describe Ci::UpdateClusterService do
   describe '#execute' do
-    context 'when correct params' do
-      it 'updates the cluster and the service' do
-        
-      end
+    let(:cluster) { create(:gcp_cluster, :created_on_gke, :with_kubernetes_service) }
+
+    before do
+      described_class.new(cluster.project, cluster.user, params).execute(cluster)
+
+      cluster.reload
     end
 
-    context 'when invalid params' do
-      it 'returns a cluster object with error' do
+    context 'when correct params' do
+      context 'when enabled is true' do
+        let(:params) { { 'enabled' => 'true' } }
 
+        it 'enables cluster and overwrite kubernetes service' do
+          expect(cluster.enabled).to be_truthy
+          expect(cluster.service.active).to be_truthy
+          expect(cluster.service.api_url).to eq(cluster.api_url)
+          expect(cluster.service.ca_pem).to eq(cluster.ca_cert)
+          expect(cluster.service.namespace).to eq(cluster.project_namespace)
+          expect(cluster.service.token).to eq(cluster.kubernetes_token)
+        end
+      end
+
+      context 'when enabled is false' do
+        let(:params) { { 'enabled' => 'false' } }
+
+        it 'disables cluster and kubernetes service' do
+          expect(cluster.enabled).to be_falsy
+          expect(cluster.service.active).to be_falsy
+        end
       end
     end
   end