Merge remote-tracking branch 'origin/master' into HEAD

Conflicts:
	pkg/drivers/donut/donut.go
	pkg/storage/donut/bucket.go
	pkg/storage/donut/donut.go
	pkg/storage/donut/donut_test.go
	pkg/storage/donut/donutdriver.go

pkg/storage/donut/node_local.go

@@ -0,0 +1,91 @@
+package donut
+
+import (
+	"io"
+	"os"
+	"path"
+	"sort"
+	"strings"
+
+	"encoding/json"
+	"io/ioutil"
+	"path/filepath"
+)
+
+type localDirectoryNode struct {
+	root string
+}
+
+func (d localDirectoryNode) CreateBucket(bucket string) error {
+	objectPath := path.Join(d.root, bucket)
+	return os.MkdirAll(objectPath, 0700)
+}
+
+func (d localDirectoryNode) GetBuckets() ([]string, error) {
+	files, err := ioutil.ReadDir(d.root)
+	if err != nil {
+		return nil, err
+	}
+	var results []string
+	for _, file := range files {
+		if file.IsDir() {
+			results = append(results, file.Name())
+		}
+	}
+	return results, nil
+}
+
+func (d localDirectoryNode) GetWriter(bucket, object string) (Writer, error) {
+	objectPath := path.Join(d.root, bucket, object)
+	err := os.MkdirAll(objectPath, 0700)
+	if err != nil {
+		return nil, err
+	}
+	return newDonutObjectWriter(objectPath)
+}
+
+func (d localDirectoryNode) GetReader(bucket, object string) (io.ReadCloser, error) {
+	return os.Open(path.Join(d.root, bucket, object, "data"))
+}
+
+func (d localDirectoryNode) GetMetadata(bucket, object string) (map[string]string, error) {
+	return d.getMetadata(bucket, object, "metadata.json")
+}
+func (d localDirectoryNode) GetDonutMetadata(bucket, object string) (map[string]string, error) {
+	return d.getMetadata(bucket, object, "donutMetadata.json")
+}
+
+func (d localDirectoryNode) getMetadata(bucket, object, fileName string) (map[string]string, error) {
+	file, err := os.Open(path.Join(d.root, bucket, object, fileName))
+	defer file.Close()
+	if err != nil {
+		return nil, err
+	}
+	metadata := make(map[string]string)
+	decoder := json.NewDecoder(file)
+	if err := decoder.Decode(&metadata); err != nil {
+		return nil, err
+	}
+	return metadata, nil
+
+}
+
+func (d localDirectoryNode) ListObjects(bucketName string) ([]string, error) {
+	prefix := path.Join(d.root, bucketName)
+	var objects []string
+	if err := filepath.Walk(prefix, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if !info.IsDir() && strings.HasSuffix(path, "data") {
+			object := strings.TrimPrefix(path, prefix+"/")
+			object = strings.TrimSuffix(object, "/data")
+			objects = append(objects, object)
+		}
+		return nil
+	}); err != nil {
+		return nil, err
+	}
+	sort.Strings(objects)
+	return objects, nil
+}