Set Disk resource status to unknown when ndm pod is shutdown (#66)

This PR contains cleaning of resources when ndm pod
deleted gracefully. This will make resources state
unknown which are attached with that node when we
shutdown that node/pod. This will make sure that there are no 
stale disk resources as nodes are added/removed to cluster. 

Changes committed:
modified:   cmd/controller/controller.go
modified:   cmd/controller/diskstore.go
modified:   cmd/controller/diskstore_test.go

Signed-off-by: Shovan Maity <[email protected]>

cmd/controller/controller.go

@@ -36,6 +36,7 @@ const (
 	NDMHostKey  = "kubernetes.io/hostname" // NDMHostKey is host name label prefix.
 	NDMActive   = "Active"                 // NDMActive is constant for active resource status.
 	NDMInactive = "Inactive"               // NDMInactive is constant for inactive resource status.
+	NDMUnknown  = "Unknown"                // NDMUnknown is constant for resource unknown satus.
 )
 
 // ControllerBroadcastChannel is used to send a copy of controller object to each probe.
@@ -153,6 +154,10 @@ func (c *Controller) Broadcast() {
 func (c *Controller) run(threadiness int, stopCh <-chan struct{}) error {
 	glog.Info("started the controller")
 	<-stopCh
+	glog.Info("changing the state to unknown before shutting down.")
+	// Changing the state to unknown before shutting down. Similar as when one pod is
+	// running and you stopped kubelet it will make pod status unknown.
+	c.MarkDiskStatusToUnknown()
 	glog.Info("shutting down the controller")
 	return nil
 }

cmd/controller/diskstore.go

@@ -149,3 +149,20 @@ func (c *Controller) PushDiskResource(oldDr *apis.Disk, diskDetails *DiskInfo) {
 	}
 	c.CreateDisk(diskApi)
 }
+
+// MarkDiskStatusToUnknown makes state of all resources owned by node unknown
+// This will call as a cleanup process before shutting down.
+func (c *Controller) MarkDiskStatusToUnknown() {
+	listDR, err := c.ListDiskResource()
+	if err != nil {
+		glog.Error(err)
+		return
+	}
+	for _, item := range listDR.Items {
+		drCopy := item.DeepCopy()
+		drCopy.Status.State = NDMUnknown
+		if dr, err := c.Clientset.OpenebsV1alpha1().Disks().Update(drCopy); err == nil {
+			glog.Error("updated disk object : ", dr.ObjectMeta.Name)
+		}
+	}
+}

cmd/controller/diskstore_test.go

@@ -400,3 +400,34 @@ func TestDeactivateStaleDiskResource(t *testing.T) {
 		})
 	}
 }
+
+func TestMarkDiskStatusToUnknown(t *testing.T) {
+	fakeNdmClient := ndmFakeClientset.NewSimpleClientset()
+	fakeKubeClient := fake.NewSimpleClientset()
+	fakeController := &Controller{
+		HostName:      fakeHostName,
+		KubeClientset: fakeKubeClient,
+		Clientset:     fakeNdmClient,
+	}
+	dr := mockEmptyDiskCr()
+	dr.ObjectMeta.Labels[NDMHostKey] = fakeController.HostName
+	fakeController.CreateDisk(dr)
+
+	fakeController.MarkDiskStatusToUnknown()
+	dr.Status.State = NDMUnknown
+	cdr, err := fakeController.Clientset.OpenebsV1alpha1().Disks().Get(fakeDiskUid, metav1.GetOptions{})
+	tests := map[string]struct {
+		actualDisk    apis.Disk
+		actualError   error
+		expectedDisk  apis.Disk
+		expectedError error
+	}{
+		"DeactivateOwnedDiskResource should make all present resources state inactive": {actualDisk: *cdr, actualError: err, expectedDisk: dr, expectedError: nil},
+	}
+	for name, test := range tests {
+		t.Run(name, func(t *testing.T) {
+			assert.Equal(t, test.expectedDisk, test.actualDisk)
+			assert.Equal(t, test.expectedError, test.actualError)
+		})
+	}
+}