Put binding and job creation in one transaction

Similar as in #3567, now for service key binding and service instance
creation to be consistent with #3567.

app/controllers/v3/service_credential_bindings_controller.rb

@@ -66,7 +66,6 @@ def create
     when 'key'
       unauthorized! unless can_write_to_active_space?(service_instance.space)
       suspended! unless is_space_active?(service_instance.space)
-
       create_key_binding(message, service_instance)
     end
   rescue V3::ServiceCredentialBindingAppCreate::UnprocessableCreate,
@@ -182,10 +181,12 @@ def override_default_order_by(message)
 
   def create_key_binding(message, service_instance)
     action = V3::ServiceCredentialBindingKeyCreate.new(user_audit_info, message.audit_hash)
-    binding = action.precursor(service_instance, message:)
+    VCAP::CloudController::ServiceBinding.db.transaction do
+      binding = action.precursor(service_instance, message:)
 
-    pollable_job_guid = enqueue_bind_job(:key, binding.guid, message)
-    head :accepted, 'Location' => url_builder.build_url(path: "/v3/jobs/#{pollable_job_guid}")
+      pollable_job_guid = enqueue_bind_job(:key, binding.guid, message)
+      head :accepted, 'Location' => url_builder.build_url(path: "/v3/jobs/#{pollable_job_guid}")
+    end
   end
 
   def build_create_message(params)

app/controllers/v3/service_instances_controller.rb

@@ -257,17 +257,20 @@ def create_managed(message, space:)
     unprocessable_service_plan! unless service_plan_valid?(service_plan, space)
 
     action = V3::ServiceInstanceCreateManaged.new(user_audit_info, message.audit_hash)
-    instance = action.precursor(message:, service_plan:)
+    VCAP::CloudController::ServiceInstance.db.transaction do
+      instance = action.precursor(message:, service_plan:)
 
-    provision_job = VCAP::CloudController::V3::CreateServiceInstanceJob.new(
-      instance.guid,
-      arbitrary_parameters: message.parameters,
-      user_audit_info: user_audit_info,
-      audit_hash: message.audit_hash
-    )
-    pollable_job = Jobs::Enqueuer.new(provision_job, queue: Jobs::Queues.generic).enqueue_pollable
+      provision_job = VCAP::CloudController::V3::CreateServiceInstanceJob.new(
+        instance.guid,
+        arbitrary_parameters: message.parameters,
+        user_audit_info: user_audit_info,
+        audit_hash: message.audit_hash
+      )
+
+      pollable_job = Jobs::Enqueuer.new(provision_job, queue: Jobs::Queues.generic).enqueue_pollable
 
-    head :accepted, 'Location' => url_builder.build_url(path: "/v3/jobs/#{pollable_job.guid}")
+      head :accepted, 'Location' => url_builder.build_url(path: "/v3/jobs/#{pollable_job.guid}")
+    end
   rescue VCAP::CloudController::ServiceInstanceCreateMixin::UnprocessableOperation,
          V3::ServiceInstanceCreateManaged::InvalidManagedServiceInstance => e
     unprocessable!(e.message)

spec/request/service_instances_spec.rb

@@ -1174,6 +1174,23 @@ def check_filtered_instances(*instances)
         end
       end
 
+      describe 'when db is unavailable' do
+        before do
+          allow_any_instance_of(VCAP::CloudController::Jobs::Enqueuer).to receive(:enqueue_pollable).and_raise(Sequel::DatabaseDisconnectError)
+        end
+
+        it 'rolls back the transaction' do
+          api_call.call(admin_headers)
+
+          expect(last_response).to have_status_code(503)
+          expect(parsed_response['errors']).to include(include({
+                                                                 'detail' => include('Database connection failure'),
+                                                                 'title' => 'CF-ServiceUnavailable',
+                                                                 'code' => 10_015
+                                                               }))
+        end
+      end
+
       describe 'service plan checks' do
         context 'does not exist' do
           let(:service_plan_guid) { 'does-not-exist' }