Add Refresh method to cloud provider

This can be used to dynamically update cloud provider
config (in particular list of managed NodeGroups and their
min/max constraints).
Add GKE implementation.

cluster-autoscaler/cloudprovider/aws/aws_cloud_provider.go

@@ -165,6 +165,12 @@ func (aws *awsCloudProvider) GetResourceLimiter() (*cloudprovider.ResourceLimite
 	return aws.resourceLimiter, nil
 }
 
+// Refresh is called before every main loop and can be used to dynamically update cloud provider state.
+// In particular the list of node groups returned by NodeGroups can change as a result of CloudProvider.Refresh().
+func (aws *awsCloudProvider) Refresh() error {
+	return nil
+}
+
 // AwsRef contains a reference to some entity in AWS/GKE world.
 type AwsRef struct {
 	Name string

cluster-autoscaler/cloudprovider/cloud_provider.go

@@ -56,6 +56,10 @@ type CloudProvider interface {
 
 	// GetResourceLimiter returns struct containing limits (max, min) for resources (cores, memory etc.).
 	GetResourceLimiter() (*ResourceLimiter, error)
+
+	// Refresh is called before every main loop and can be used to dynamically update cloud provider state.
+	// In particular the list of node groups returned by NodeGroups can change as a result of CloudProvider.Refresh().
+	Refresh() error
 }
 
 // ErrNotImplemented is returned if a method is not implemented.

cluster-autoscaler/cloudprovider/gce/gce_cloud_provider.go

@@ -162,6 +162,12 @@ func (gce *GceCloudProvider) GetResourceLimiter() (*cloudprovider.ResourceLimite
 	return gce.resourceLimiter, nil
 }
 
+// Refresh is called before every main loop and can be used to dynamically update cloud provider state.
+// In particular the list of node groups returned by NodeGroups can change as a result of CloudProvider.Refresh().
+func (gce *GceCloudProvider) Refresh() error {
+	return gce.gceManager.Refresh()
+}
+
 // GceRef contains s reference to some entity in GCE/GKE world.
 type GceRef struct {
 	Project string

cluster-autoscaler/cloudprovider/gce/gce_cloud_provider_test.go

@@ -72,6 +72,11 @@ func (m *gceManagerMock) GetMigNodes(mig *Mig) ([]string, error) {
 	return args.Get(0).([]string), args.Error(1)
 }
 
+func (m *gceManagerMock) Refresh() error {
+	args := m.Called()
+	return args.Error(0)
+}
+
 func (m *gceManagerMock) getMigs() []*migInformation {
 	args := m.Called()
 	return args.Get(0).([]*migInformation)

cluster-autoscaler/cloudprovider/gce/gce_manager.go

@@ -57,6 +57,7 @@ const (
 	operationWaitTimeout       = 5 * time.Second
 	gkeOperationWaitTimeout    = 120 * time.Second
 	operationPollInterval      = 100 * time.Millisecond
+	refreshInterval            = 1 * time.Minute
 	nodeAutoprovisioningPrefix = "nap"
 	napMaxNodes                = 1000
 	napMinNodes                = 0
@@ -91,6 +92,8 @@ type GceManager interface {
 	GetMigForInstance(instance *GceRef) (*Mig, error)
 	// GetMigNodes returns mig nodes.
 	GetMigNodes(mig *Mig) ([]string, error)
+	// Refresh updates config by calling GKE API (in GKE mode only).
+	Refresh() error
 	getMigs() []*migInformation
 	createNodePool(mig *Mig) error
 	deleteNodePool(toBeRemoved *Mig) error
@@ -117,6 +120,8 @@ type gceManagerImpl struct {
 	clusterName string
 	mode        GcpCloudProviderMode
 	templates   *templateBuilder
+
+	lastRefresh time.Time
 }
 
 // CreateGceManager constructs gceManager object.
@@ -215,6 +220,8 @@ func CreateGceManager(configReader io.Reader, mode GcpCloudProviderMode, cluster
 		glog.V(1).Info("Using GKE-NAP mode")
 	}
 
+	manager.lastRefresh = time.Now()
+
 	go wait.Forever(func() {
 		manager.cacheMutex.Lock()
 		defer manager.cacheMutex.Unlock()
@@ -691,6 +698,19 @@ func (m *gceManagerImpl) getTemplates() *templateBuilder {
 	return m.templates
 }
 
+func (m *gceManagerImpl) Refresh() error {
+	if m.mode == ModeGCE {
+		return nil
+	}
+	if m.lastRefresh.Add(refreshInterval).Before(time.Now()) {
+		err := m.fetchAllNodePools()
+		m.lastRefresh = time.Now()
+		glog.V(2).Infof("Refreshed NodePools list, next refresh after %v", m.lastRefresh.Add(refreshInterval))
+		return err
+	}
+	return nil
+}
+
 // Code borrowed from gce cloud provider. Reuse the original as soon as it becomes public.
 func getProjectAndZone() (string, string, error) {
 	result, err := metadata.Get("instance/zone")

cluster-autoscaler/cloudprovider/kubemark/kubemark_linux.go

@@ -122,6 +122,12 @@ func (kubemark *KubemarkCloudProvider) GetResourceLimiter() (*cloudprovider.Reso
 	return kubemark.resourceLimiter, nil
 }
 
+// Refresh is called before every main loop and can be used to dynamically update cloud provider state.
+// In particular the list of node groups returned by NodeGroups can change as a result of CloudProvider.Refresh().
+func (kubemark *KubemarkCloudProvider) Refresh() error {
+	return nil
+}
+
 // NodeGroup implements NodeGroup interfrace.
 type NodeGroup struct {
 	Name               string

cluster-autoscaler/cloudprovider/kubemark/kubemark_other.go

@@ -64,3 +64,9 @@ func (kubemark *KubemarkCloudProvider) NewNodeGroup(machineType string, labels m
 func (kubemark *KubemarkCloudProvider) GetResourceLimiter() (*cloudprovider.ResourceLimiter, error) {
 	return nil, cloudprovider.ErrNotImplemented
 }
+
+// Refresh is called before every main loop and can be used to dynamically update cloud provider state.
+// In particular the list of node groups returned by NodeGroups can change as a result of CloudProvider.Refresh().
+func (kubemark *KubemarkCloudProvider) Refresh() error {
+	return cloudprovider.ErrNotImplemented
+}

cluster-autoscaler/cloudprovider/test/test_cloud_provider.go

@@ -192,6 +192,12 @@ func (tcp *TestCloudProvider) SetResourceLimiter(resourceLimiter *cloudprovider.
 	tcp.resourceLimiter = resourceLimiter
 }
 
+// Refresh is called before every main loop and can be used to dynamically update cloud provider state.
+// In particular the list of node groups returned by NodeGroups can change as a result of CloudProvider.Refresh().
+func (tcp *TestCloudProvider) Refresh() error {
+	return nil
+}
+
 // TestNodeGroup is a node group used by TestCloudProvider.
 type TestNodeGroup struct {
 	sync.Mutex

cluster-autoscaler/core/static_autoscaler.go

@@ -95,6 +95,12 @@ func (a *StaticAutoscaler) RunOnce(currentTime time.Time) errors.AutoscalerError
 
 	glog.V(4).Info("Starting main loop")
 
+	err := autoscalingContext.CloudProvider.Refresh()
+	if err != nil {
+		glog.Errorf("Failed to refresh cloud provider config: %v", err)
+		return errors.ToAutoscalerError(errors.CloudProviderError, err)
+	}
+
 	readyNodes, err := readyNodeLister.List()
 	if err != nil {
 		glog.Errorf("Failed to list ready nodes: %v", err)