Merge pull request #135 from ddysher/detect-capacity

Detect local volume capacity

local-volume/provisioner/deployment/kubernetes/provisioner-daemonset.yaml

@@ -12,6 +12,8 @@ spec:
       - name: provisioner
         image: "gcr.io/msau-k8s-dev/local-volume-provisioner:latest"
         imagePullPolicy: Always
+        securityContext:
+          privileged: true
         volumeMounts:
         - name: discovery-vol
           mountPath: "/local-disks"

local-volume/provisioner/pkg/common/common.go

@@ -65,6 +65,7 @@ type RuntimeConfig struct {
 type LocalPVConfig struct {
 	Name            string
 	HostPath        string
+	Capacity        uint64
 	StorageClass    string
 	ProvisionerName string
 	AffinityAnn     string
@@ -83,8 +84,7 @@ func CreateLocalPVSpec(config *LocalPVConfig) *v1.PersistentVolume {
 		Spec: v1.PersistentVolumeSpec{
 			PersistentVolumeReclaimPolicy: v1.PersistentVolumeReclaimDelete,
 			Capacity: v1.ResourceList{
-				// TODO: detect capacity
-				v1.ResourceName(v1.ResourceStorage): resource.MustParse("10Gi"),
+				v1.ResourceName(v1.ResourceStorage): *resource.NewQuantity(int64(config.Capacity), resource.BinarySI),
 			},
 			PersistentVolumeSource: v1.PersistentVolumeSource{
 				Local: &v1.LocalVolumeSource{

local-volume/provisioner/pkg/discovery/discovery.go

@@ -105,8 +105,13 @@ func (d *Discoverer) discoverVolumesAtPath(class, relativePath string) {
 				glog.Errorf("Mount path %q validation failed: %v", filePath, err)
 				continue
 			}
-			// TODO: detect capacity
-			d.createPV(file, relativePath, class)
+
+			availByte, err := d.VolUtil.GetFsAvailableByte(filePath)
+			if err != nil {
+				glog.Errorf("Path %q fs stats error: %v", filePath, err)
+				continue
+			}
+			d.createPV(file, relativePath, class, availByte)
 		}
 	}
 }
@@ -131,14 +136,15 @@ func generatePVName(file, node, class string) string {
 	return fmt.Sprintf("local-pv-%x", h.Sum32())
 }
 
-func (d *Discoverer) createPV(file, relativePath, class string) {
+func (d *Discoverer) createPV(file, relativePath, class string, availByte uint64) {
 	pvName := generatePVName(file, d.Node.Name, class)
 	outsidePath := filepath.Join(d.HostDir, relativePath, file)
 
-	glog.Infof("Found new volume at host path %q, creating Local PV %q", outsidePath, pvName)
+	glog.Infof("Found new volume at host path %q with capacity %d, creating Local PV %q", outsidePath, availByte, pvName)
 	pvSpec := common.CreateLocalPVSpec(&common.LocalPVConfig{
 		Name:            pvName,
 		HostPath:        outsidePath,
+		Capacity:        availByte,
 		StorageClass:    class,
 		ProvisionerName: d.Name,
 		AffinityAnn:     d.nodeAffinityAnn,

local-volume/provisioner/pkg/discovery/discovery_test.go

@@ -69,8 +69,8 @@ type testConfig struct {
 func TestDiscoverVolumes_Basic(t *testing.T) {
 	vols := map[string][]*util.FakeFile{
 		"dir1": {
-			{Name: "mount1", Hash: 0xaaaafef5},
-			{Name: "mount2", Hash: 0x79412c38},
+			{Name: "mount1", Hash: 0xaaaafef5, Capacity: 100 * 1024},
+			{Name: "mount2", Hash: 0x79412c38, Capacity: 100 * 1024 * 1024},
 		},
 		"dir2": {
 			{Name: "mount1", Hash: 0xa7aafa3c},
@@ -311,13 +311,20 @@ func verifyProvisionerName(t *testing.T, pv *v1.PersistentVolume) {
 	}
 }
 
+// testPVInfo contains all the fields we are intested in validating.
+type testPVInfo struct {
+	pvName   string
+	path     string
+	capacity uint64
+}
+
 func verifyCreatedPVs(t *testing.T, test *testConfig) {
-	expectedPVs := map[string]string{}
+	expectedPVs := map[string]*testPVInfo{}
 	for dir, files := range test.expectedVolumes {
 		for _, file := range files {
 			pvName := fmt.Sprintf("local-pv-%x", file.Hash)
 			path := filepath.Join(testHostDir, dir, file.Name)
-			expectedPVs[pvName] = path
+			expectedPVs[pvName] = &testPVInfo{pvName: pvName, path: path, capacity: file.Capacity}
 		}
 	}
 
@@ -328,21 +335,32 @@ func verifyCreatedPVs(t *testing.T, test *testConfig) {
 		t.Errorf("Expected %v created PVs, got %v", expectedLen, actualLen)
 	}
 
-	for pvName, pv := range createdPVs {
-		expectedPath, found := expectedPVs[pvName]
+	for pvName, createdPV := range createdPVs {
+		expectedPV, found := expectedPVs[pvName]
 		if !found {
 			t.Errorf("Did not expect created PVs %v", pvName)
 		}
-		if pv.Spec.PersistentVolumeSource.Local.Path != expectedPath {
-			t.Errorf("Expected path %q, got %q", expectedPath, expectedPath)
+		if createdPV.Spec.PersistentVolumeSource.Local.Path != expectedPV.path {
+			t.Errorf("Expected path %q, got %q", expectedPV.path, createdPV.Spec.PersistentVolumeSource.Local.Path)
 		}
 		_, exists := test.cache.GetPV(pvName)
 		if !exists {
 			t.Errorf("PV %q not in cache", pvName)
 		}
+		capacity, ok := createdPV.Spec.Capacity[v1.ResourceStorage]
+		if !ok {
+			t.Errorf("Unexpected empty resource storage")
+		}
+		capacityInt, ok := capacity.AsInt64()
+		if !ok {
+			t.Errorf("Unable to convert resource storage into int64")
+		}
+		if uint64(capacityInt) != expectedPV.capacity {
+			t.Errorf("Expected capacity %d, got %d", expectedPV.capacity, capacityInt)
+		}
 		// TODO: verify storage class
-		verifyProvisionerName(t, pv)
-		verifyNodeAffinity(t, pv)
+		verifyProvisionerName(t, createdPV)
+		verifyNodeAffinity(t, createdPV)
 	}
 }
 

local-volume/provisioner/pkg/util/volume_util.go

@@ -21,6 +21,8 @@ import (
 	"os"
 	"path/filepath"
 
+	"golang.org/x/sys/unix"
+
 	"github.com/golang/glog"
 )
 
@@ -34,6 +36,9 @@ type VolumeUtil interface {
 
 	// Delete all the contents under the given path, but not the path itself
 	DeleteContents(fullPath string) error
+
+	// Get available capacity for fs on full path
+	GetFsAvailableByte(fullPath string) (uint64, error)
 }
 
 var _ VolumeUtil = &volumeUtil{}
@@ -99,6 +104,18 @@ func (u *volumeUtil) DeleteContents(fullPath string) error {
 	return nil
 }
 
+// GetFsAvailableByte returns available capacity in byte about a mounted filesystem.
+// fullPath is the pathname of any file within the mounted filesystem. Capacity
+// returned here is total capacity available to non-root users, and does not include
+// fs reserved space.
+func (u *volumeUtil) GetFsAvailableByte(fullPath string) (uint64, error) {
+	var s unix.Statfs_t
+	if err := unix.Statfs(fullPath, &s); err != nil {
+		return 0, err
+	}
+	return uint64(s.Frsize) * (s.Blocks - s.Bfree + s.Bavail), nil
+}
+
 var _ VolumeUtil = &FakeVolumeUtil{}
 
 // FakeVolumeUtil is a stub interface for unit testing
@@ -114,7 +131,8 @@ type FakeFile struct {
 	Name     string
 	IsNotDir bool
 	// Expected hash value of the PV name
-	Hash uint32
+	Hash     uint32
+	Capacity uint64
 }
 
 // NewFakeVolumeUtil returns a VolumeUtil object for use in unit testing
@@ -163,6 +181,22 @@ func (u *FakeVolumeUtil) DeleteContents(fullPath string) error {
 	return nil
 }
 
+func (u *FakeVolumeUtil) GetFsAvailableByte(fullPath string) (uint64, error) {
+	dir, file := filepath.Split(fullPath)
+	dir = filepath.Clean(dir)
+	files, found := u.directoryFiles[dir]
+	if !found {
+		return 0, fmt.Errorf("Directory %q not found", dir)
+	}
+
+	for _, f := range files {
+		if file == f.Name {
+			return f.Capacity, nil
+		}
+	}
+	return 0, fmt.Errorf("File %q not found", fullPath)
+}
+
 // AddNewFiles adds the given files to the current directory listing
 // This is only for testing
 func (u *FakeVolumeUtil) AddNewFiles(mountDir string, dirFiles map[string][]*FakeFile) {