Fix fs stats handling for non-aufs storage drivers.

Signed-off-by: Vishnu kannan <vishnuk@google.com>

client/v2/client.go

@@ -121,7 +121,7 @@ func (self *Client) attributesUrl() string {
 }
 
 func (self *Client) statsUrl(name string) string {
-	return path.Join(self.baseUrl, "stats", name)
+	return self.baseUrl + path.Join("stats", name)
 }
 
 func (self *Client) httpGetResponse(postData interface{}, urlPath, infoName string) ([]byte, error) {

container/docker/factory.go

@@ -15,7 +15,6 @@
 package docker
 
 import (
-	"encoding/json"
 	"flag"
 	"fmt"
 	"path"
@@ -106,8 +105,8 @@ const (
 type dockerFactory struct {
 	machineInfoFactory info.MachineInfoFactory
 
-	storageDriver    storageDriver
-	storageDriverDir string
+	storageDriver storageDriver
+	storageDir    string
 
 	client *docker.Client
 
@@ -138,7 +137,7 @@ func (self *dockerFactory) NewContainerHandler(name string, inHostNamespace bool
 		self.machineInfoFactory,
 		self.fsInfo,
 		self.storageDriver,
-		self.storageDriverDir,
+		self.storageDir,
 		&self.cgroupSubsystems,
 		inHostNamespace,
 		metadataEnvs,
@@ -215,37 +214,6 @@ func parseDockerVersion(full_version_string string) ([]int, error) {
 	return version_array, nil
 }
 
-func getStorageDir(dockerInfo *docker.Env) (string, error) {
-	storageDriverInfo := dockerInfo.GetList("DriverStatus")
-	if len(storageDriverInfo) == 0 {
-		return "", fmt.Errorf("failed to find docker storage driver options")
-	}
-
-	var storageDir string
-	for _, data := range storageDriverInfo {
-		if data == "" {
-			continue
-		}
-		var parts [][]string
-		if err := json.Unmarshal([]byte(data), &parts); err != nil {
-			return "", fmt.Errorf("failed to parse docker storage driver options - %+v", data)
-		}
-		for _, part := range parts {
-			if len(part) != 2 {
-				return "", fmt.Errorf("failed to parse docker storage driver options - %+v", part)
-			}
-			if part[0] == dockerRootDirKey {
-				storageDir = part[1]
-				break
-			}
-		}
-	}
-	if storageDir == "" {
-		return "", fmt.Errorf("failed to find docker storage directory from docker info. Expected key %q in storage driver info %v", dockerRootDirKey, storageDriverInfo)
-	}
-	return storageDir, nil
-}
-
 // Register root container before running this function!
 func Register(factory info.MachineInfoFactory, fsInfo fs.FsInfo) error {
 	if UseSystemd() {
@@ -291,10 +259,9 @@ func Register(factory info.MachineInfoFactory, fsInfo fs.FsInfo) error {
 		return fmt.Errorf("failed to find docker storage driver")
 	}
 
-	storageDir, err := getStorageDir(information)
-	if err != nil {
-		glog.V(2).Infof("failed to detect storage directory from docker. Defaulting to using the value in --docker_root: %q", err, *dockerRootDir)
-		storageDir = path.Join(*dockerRootDir, sd)
+	storageDir := information.Get("DockerRootDir")
+	if storageDir == "" {
+		storageDir = *dockerRootDir
 	}
 	cgroupSubsystems, err := libcontainer.GetCgroupSubsystems()
 	if err != nil {
@@ -309,7 +276,7 @@ func Register(factory info.MachineInfoFactory, fsInfo fs.FsInfo) error {
 		fsInfo:             fsInfo,
 		machineInfoFactory: factory,
 		storageDriver:      storageDriver(sd),
-		storageDriverDir:   storageDir,
+		storageDir:         storageDir,
 	}
 	container.RegisterContainerHandlerFactory(f)
 	return nil

container/docker/handler.go

@@ -83,18 +83,19 @@ type dockerContainerHandler struct {
 	fsHandler fsHandler
 }
 
-func getRwLayerID(containerID, storageDriverDir string, dockerVersion []int) (string, error) {
+func getRwLayerID(containerID, storageDir string, sd storageDriver, dockerVersion []int) (string, error) {
 	const (
 		// Docker version >=1.10.0 have a randomized ID for the root fs of a container.
 		randomizedRWLayerMinorVersion = 10
 		// Directory where the file containinig the randomized ID of the root fs of a container is stored in versions >= 1.10.0
-		rwLayerIDDir  = "../image/aufs/layerdb/mounts/"
-		rwLayerIDFile = "mount-id"
+		rwLayerIDDirTemplate = "image/%s/layerdb/mounts/"
+		rwLayerIDFile        = "mount-id"
 	)
 	if (dockerVersion[0] <= 1) && (dockerVersion[1] < randomizedRWLayerMinorVersion) {
 		return containerID, nil
 	}
-	bytes, err := ioutil.ReadFile(path.Join(storageDriverDir, rwLayerIDDir, containerID, rwLayerIDFile))
+
+	bytes, err := ioutil.ReadFile(path.Join(storageDir, "image", string(sd), "layerdb", "mounts", containerID, rwLayerIDFile))
 	if err != nil {
 		return "", fmt.Errorf("failed to identify the read-write layer ID for container %q. - %v", containerID, err)
 	}
@@ -107,7 +108,7 @@ func newDockerContainerHandler(
 	machineInfoFactory info.MachineInfoFactory,
 	fsInfo fs.FsInfo,
 	storageDriver storageDriver,
-	storageDriverDir string,
+	storageDir string,
 	cgroupSubsystems *containerlibcontainer.CgroupSubsystems,
 	inHostNamespace bool,
 	metadataEnvs []string,
@@ -135,18 +136,18 @@ func newDockerContainerHandler(
 	id := ContainerNameToDockerId(name)
 
 	// Add the Containers dir where the log files are stored.
-	otherStorageDir := path.Join(path.Dir(storageDriverDir), pathToContainersDir, id)
+	otherStorageDir := path.Join(storageDir, pathToContainersDir, id)
 
-	rwLayerID, err := getRwLayerID(id, storageDriverDir, dockerVersion)
+	rwLayerID, err := getRwLayerID(id, storageDir, storageDriver, dockerVersion)
 	if err != nil {
 		return nil, err
 	}
 	var rootfsStorageDir string
 	switch storageDriver {
 	case aufsStorageDriver:
-		rootfsStorageDir = path.Join(storageDriverDir, aufsRWLayer, rwLayerID)
+		rootfsStorageDir = path.Join(storageDir, string(aufsStorageDriver), aufsRWLayer, rwLayerID)
 	case overlayStorageDriver:
-		rootfsStorageDir = path.Join(storageDriverDir, rwLayerID)
+		rootfsStorageDir = path.Join(storageDir, string(overlayStorageDriver), rwLayerID)
 	}
 
 	handler := &dockerContainerHandler{

container/docker/handler_test.go

@@ -26,7 +26,7 @@ import (
 
 func TestStorageDirDetectionWithOldVersions(t *testing.T) {
 	as := assert.New(t)
-	rwLayer, err := getRwLayerID("abcd", "/", []int{1, 9, 0})
+	rwLayer, err := getRwLayerID("abcd", "/", aufsStorageDriver, []int{1, 9, 0})
 	as.Nil(err)
 	as.Equal(rwLayer, "abcd")
 }
@@ -40,10 +40,10 @@ func TestStorageDirDetectionWithNewVersions(t *testing.T) {
 	randomIDPath := path.Join(testDir, "image/aufs/layerdb/mounts/", containerID)
 	as.Nil(os.MkdirAll(randomIDPath, os.ModePerm))
 	as.Nil(ioutil.WriteFile(path.Join(randomIDPath, "mount-id"), []byte(randomizedID), os.ModePerm))
-	rwLayer, err := getRwLayerID(containerID, path.Join(testDir, "aufs"), []int{1, 10, 0})
+	rwLayer, err := getRwLayerID(containerID, testDir, "aufs", []int{1, 10, 0})
 	as.Nil(err)
 	as.Equal(rwLayer, randomizedID)
-	rwLayer, err = getRwLayerID(containerID, path.Join(testDir, "aufs"), []int{1, 10, 0})
+	rwLayer, err = getRwLayerID(containerID, testDir, "aufs", []int{1, 10, 0})
 	as.Nil(err)
 	as.Equal(rwLayer, randomizedID)