Move DefaultLeaseDuration... parameters to controller pkg and flesh o…

…ut code doc comments

aws/efs/cmd/efs-provisioner/efs-provisioner.go

@@ -33,7 +33,6 @@ import (
  "github.com/golang/glog"
  "github.com/kubernetes-incubator/external-storage/aws/efs/pkg/gidallocator"
  "github.com/kubernetes-incubator/external-storage/lib/controller"
- "github.com/kubernetes-incubator/external-storage/lib/leaderelection"
  metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
  "k8s.io/apimachinery/pkg/util/wait"
  "k8s.io/client-go/kubernetes"
@@ -49,10 +48,10 @@ const (
  resyncPeriod = 15 * time.Second
  exponentialBackOffOnError = true
  failedRetryThreshold = 5
- leasePeriod = leaderelection.DefaultLeaseDuration
- retryPeriod = leaderelection.DefaultRetryPeriod
- renewDeadline = leaderelection.DefaultRenewDeadline
- termLimit = leaderelection.DefaultTermLimit
+ leasePeriod = controller.DefaultLeaseDuration
+ retryPeriod = controller.DefaultRetryPeriod
+ renewDeadline = controller.DefaultRenewDeadline
+ termLimit = controller.DefaultTermLimit
 )
 
 type efsProvisioner struct {

gluster/block/glusterblock-provisioner.go

@@ -28,7 +28,6 @@ import (
 
  "github.com/golang/glog"
  "github.com/kubernetes-incubator/external-storage/lib/controller"
- "github.com/kubernetes-incubator/external-storage/lib/leaderelection"
  metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
  "k8s.io/apimachinery/pkg/types"
  "k8s.io/apimachinery/pkg/util/uuid"
@@ -47,10 +46,10 @@ const (
  failedRetryThreshold = 5
  defaultExecPath = "./createiscsi"
  secretKeyName = "key"
- leasePeriod = leaderelection.DefaultLeaseDuration
- retryPeriod = leaderelection.DefaultRetryPeriod
- renewDeadline = leaderelection.DefaultRenewDeadline
- termLimit = leaderelection.DefaultTermLimit
+ leasePeriod = controller.DefaultLeaseDuration
+ retryPeriod = controller.DefaultRetryPeriod
+ renewDeadline = controller.DefaultRenewDeadline
+ termLimit = controller.DefaultTermLimit
 )
 
 type glusterBlockProvisioner struct {

lib/controller/controller.go

@@ -68,6 +68,27 @@ const createProvisionedPVRetryCount = 5
 // Interval between retries when we create a PV object for a provisioned volume.
 const createProvisionedPVInterval = 10 * time.Second
 
+const (
+ // DefaultLeaseDuration is a suggested controller LeaseDuration:
+ // LeaseDuration is the duration that non-leader candidates will
+ // wait to force acquire leadership. This is measured against time of
+ // last observed ack.
+ DefaultLeaseDuration = 15 * time.Second
+ // DefaultRenewDeadline is a suggested controller RenewDeadline:
+ // RenewDeadline is the duration that the acting master will retry
+ // refreshing leadership before giving up.
+ DefaultRenewDeadline = 10 * time.Second
+ // DefaultRetryPeriod is a suggested controller RetryPeriod:
+ // RetryPeriod is the duration the LeaderElector clients should wait
+ // between tries of actions.
+ DefaultRetryPeriod = 2 * time.Second
+ // DefaultTermLimit is a suggested controller TermLimit:
+ // TermLimit is the maximum duration that a leader may remain the leader
+ // to complete the task before it must give up its leadership. 0 for forever
+ // or indefinite.
+ DefaultTermLimit = 30 * time.Second
+)
+
 // ProvisionController is a controller that provisions PersistentVolumes for
 // PersistentVolumeClaims.
 type ProvisionController struct {
@@ -119,24 +140,29 @@ type ProvisionController struct {
  // Interval between retries when we create a PV object for a provisioned volume.
  createProvisionedPVInterval time.Duration
 
- // Identity of this controller, generated at creation time.
+ // Identity of this controller, generated at creation time and not persisted
+ // across restarts. Useful only for debugging, for seeing the source of
+ // events. controller.provisioner may have its own, different notion of
+ // identity which may/may not persist across restarts
  identity types.UID
 
- // Parameters of LeaderElectionConfig: set to defaults except in tests
+ // Parameters of leaderelection.LeaderElectionConfig. Leader election is for
+ // when multiple controllers are running: they race to lock (lead) every PVC
+ // so that only one calls Provision for it (saving API calls, CPU cycles...)
+ // Descriptions of each can be found in the leaderelection package and
+ // reproduced above (DefaultLeaseDuration...)
  leaseDuration, renewDeadline, retryPeriod, termLimit time.Duration
 
  // Map of claim UID to LeaderElector: for checking if this controller
  // is the leader of a given claim
  leaderElectors map[types.UID]*leaderelection.LeaderElector
+ mapMutex *sync.Mutex
 
- mapMutex *sync.Mutex
-
- // threshold for max number of retries on failure of provisioner
+ // Threshold for max number of retries on failure of provisioner
  failedRetryThreshold int
 
- // map of failed claims
- failedClaimsStats map[types.UID]int
-
+ // Map of failed claims
+ failedClaimsStats map[types.UID]int
  failedClaimsStatsMutex *sync.Mutex
 }
 

lib/controller/controller_test.go

@@ -25,7 +25,6 @@ import (
  "testing"
  "time"
 
- "github.com/kubernetes-incubator/external-storage/lib/leaderelection"
  rl "github.com/kubernetes-incubator/external-storage/lib/leaderelection/resourcelock"
  "k8s.io/apimachinery/pkg/api/resource"
  metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -246,7 +245,7 @@ func TestMultipleControllers(t *testing.T) {
  ctrls := make([]*ProvisionController, test.numControllers)
  stopChs := make([]chan struct{}, test.numControllers)
  for i := 0; i < test.numControllers; i++ {
- ctrls[i] = NewProvisionController(client, 15*time.Second, test.provisionerName, provisioner, "v1.5.0", false, failedRetryThreshold, leaderelection.DefaultLeaseDuration, leaderelection.DefaultRenewDeadline, leaderelection.DefaultRetryPeriod, leaderelection.DefaultTermLimit)
+ ctrls[i] = NewProvisionController(client, 15*time.Second, test.provisionerName, provisioner, "v1.5.0", false, failedRetryThreshold, DefaultLeaseDuration, DefaultRenewDeadline, DefaultRetryPeriod, DefaultTermLimit)
  ctrls[i].createProvisionedPVInterval = 10 * time.Millisecond
  ctrls[i].claimSource = claimSource
  ctrls[i].claims.Add(newClaim("claim-1", "uid-1-1", "class-1", "", nil))

lib/leaderelection/leaderelection.go

@@ -39,11 +39,7 @@ import (
 )
 
 const (
- JitterFactor = 1.2
- DefaultLeaseDuration = 15 * time.Second
- DefaultRenewDeadline = 10 * time.Second
- DefaultRetryPeriod = 2 * time.Second
- DefaultTermLimit = 30 * time.Second
+ JitterFactor = 1.2
 )
 
 // NewLeaderElector creates a LeaderElector from a LeaderElecitionConfig

nfs/cmd/nfs-provisioner/main.go

@@ -23,7 +23,6 @@ import (
 
  "github.com/golang/glog"
  "github.com/kubernetes-incubator/external-storage/lib/controller"
- "github.com/kubernetes-incubator/external-storage/lib/leaderelection"
  "github.com/kubernetes-incubator/external-storage/nfs/pkg/server"
  vol "github.com/kubernetes-incubator/external-storage/nfs/pkg/volume"
  "k8s.io/apimachinery/pkg/util/validation"
@@ -50,10 +49,10 @@ var (
 const (
  exportDir = "/export"
  ganeshaConfig = "/export/vfs.conf"
- leasePeriod = leaderelection.DefaultLeaseDuration
- retryPeriod = leaderelection.DefaultRetryPeriod
- renewDeadline = leaderelection.DefaultRenewDeadline
- termLimit = leaderelection.DefaultTermLimit
+ leasePeriod = controller.DefaultLeaseDuration
+ retryPeriod = controller.DefaultRetryPeriod
+ renewDeadline = controller.DefaultRenewDeadline
+ termLimit = controller.DefaultTermLimit
 )
 
 func main() {