v3: cannot create SI for non-available broker

[#168400228](https://www.pivotaltracker.com/story/show/168400228)

Author: Derik Evangelista

app/controllers/v3/service_instances_controller.rb

@@ -189,6 +189,8 @@ def create_managed(message, space:)
       visible_to_current_user?(plan: service_plan) &&
       service_plan.visible_in_space?(space)
 
+    broker_unavailable! unless service_plan.service_broker.available?
+
     job = ServiceInstanceCreateManaged.new(service_event_repository).create(message)
 
     url_builder = VCAP::CloudController::Presenters::ApiUrlBuilder.new
@@ -277,4 +279,8 @@ def unprocessable_space!
   def unprocessable_service_plan!
     unprocessable!('Invalid service plan. Ensure that the service plan exists and you have access to it.')
   end
+
+  def broker_unavailable!
+    unprocessable!('The service instance cannot be created because there is an operation in progress for the service broker')
+  end
 end

app/models/services/service_broker.rb

@@ -38,6 +38,10 @@ def in_transitional_state?
       [ServiceBrokerStateEnum::SYNCHRONIZING, ServiceBrokerStateEnum::DELETE_IN_PROGRESS].include?(self.state)
     end
 
+    def available?
+      self.state == ServiceBrokerStateEnum::AVAILABLE
+    end
+
     def space_scoped?
       !!space_id
     end

spec/request/service_instances_spec.rb

@@ -933,6 +933,30 @@ def check_filtered_instances(*instances)
         end
       end
 
+      context 'when there is an operation in progress for the service broker' do
+        let(:service_broker) { service_plan.service_broker }
+
+        before do
+          service_broker.update(state: broker_state)
+        end
+
+        context 'when the service broker is being deleted' do
+          let(:broker_state) {  VCAP::CloudController::ServiceBrokerStateEnum::DELETE_IN_PROGRESS }
+          it 'fails to create a service instance' do
+            api_call.call(space_dev_headers)
+            expect(last_response).to have_status_code(422)
+          end
+        end
+
+        context 'when the service broker is synchronising the catalog' do
+          let(:broker_state) {  VCAP::CloudController::ServiceBrokerStateEnum::SYNCHRONIZING }
+          it 'fails to create a service instance' do
+            api_call.call(space_dev_headers)
+            expect(last_response).to have_status_code(422)
+          end
+        end
+      end
+
       describe 'service plan checks' do
         context 'does not exist' do
           let(:service_plan_guid) { 'does-not-exist' }

spec/support/fakes/blueprints.rb

@@ -460,6 +460,7 @@ module VCAP::CloudController
   ServiceBroker.blueprint do
     name              { Sham.name }
     broker_url        { Sham.url }
+    state             { ServiceBrokerStateEnum::AVAILABLE }
     auth_username     { Sham.auth_username }
     auth_password     { Sham.auth_password }
   end

spec/unit/models/services/service_broker_spec.rb

@@ -93,6 +93,31 @@ module VCAP::CloudController
       end
     end
 
+    describe '#available?' do
+      let(:broker) { ServiceBroker.make }
+
+      it 'returns false when state is SYNCHRONIZING' do
+        broker.state = ServiceBrokerStateEnum::SYNCHRONIZING
+        expect(broker.available?).to eq false
+      end
+      it 'returns false when state is SYNCHRONIZATION_FAILED' do
+        broker.state = ServiceBrokerStateEnum::SYNCHRONIZATION_FAILED
+        expect(broker.available?).to eq false
+      end
+      it 'returns true when state is AVAILABLE' do
+        broker.state = ServiceBrokerStateEnum::AVAILABLE
+        expect(broker.available?).to eq true
+      end
+      it 'returns false when state is DELETE_IN_PROGRESS' do
+        broker.state = ServiceBrokerStateEnum::DELETE_IN_PROGRESS
+        expect(broker.available?).to eq false
+      end
+      it 'returns false when state is DELETE_FAILED' do
+        broker.state = ServiceBrokerStateEnum::DELETE_FAILED
+        expect(broker.available?).to eq false
+      end
+    end
+
     describe '#destroy' do
       let(:service_broker) { ServiceBroker.make }