Adding donut backend and setting as default

pkg/storage/donut/donut.go

@@ -1,6 +1,8 @@
 package donut
 
-import "io"
+import (
+	"io"
+)
 
 // INTERFACES
 
@@ -21,6 +23,7 @@ type Bucket interface {
 
 // Node interface
 type Node interface {
+	CreateBucket(bucket string) error
 	GetBuckets() ([]string, error)
 	GetDonutMetadata(bucket, object string) (map[string]string, error)
 	GetMetadata(bucket, object string) (map[string]string, error)

pkg/storage/donut/donutdriver.go

@@ -35,6 +35,9 @@ func (driver donutDriver) CreateBucket(bucketName string) error {
 		nodes := make([]string, 16)
 		for i := 0; i < 16; i++ {
 			nodes[i] = "localhost"
+			if node, ok := driver.nodes["localhost"]; ok {
+				node.CreateBucket(bucketName + ":0:" + strconv.Itoa(i))
+			}
 		}
 		bucket := bucketDriver{
 			nodes: nodes,
@@ -63,7 +66,15 @@ func (driver donutDriver) GetObjectWriter(bucketName, objectName string) (Object
 		}
 		for i, nodeID := range nodes {
 			if node, ok := driver.nodes[nodeID]; ok == true {
-				writer, _ := node.GetWriter(bucketName+":0:"+strconv.Itoa(i), objectName)
+				writer, err := node.GetWriter(bucketName+":0:"+strconv.Itoa(i), objectName)
+				if err != nil {
+					for _, writerToClose := range writers {
+						if writerToClose != nil {
+							writerToClose.CloseWithError(err)
+						}
+					}
+					return nil, err
+				}
 				writers[i] = writer
 			}
 		}
@@ -111,7 +122,19 @@ func (driver donutDriver) GetObjectMetadata(bucketName, object string) (map[stri
 			return nil, err
 		}
 		if node, ok := driver.nodes[nodes[0]]; ok {
-			return node.GetMetadata(bucketName+":0:0", object)
+			bucketID := bucketName + ":0:0"
+			metadata, err := node.GetMetadata(bucketID, object)
+			if err != nil {
+				return nil, err
+			}
+			donutMetadata, err := node.GetDonutMetadata(bucketID, object)
+			if err != nil {
+				return nil, err
+			}
+			metadata["sys.created"] = donutMetadata["created"]
+			metadata["sys.md5"] = donutMetadata["md5"]
+			metadata["sys.size"] = donutMetadata["size"]
+			return metadata, nil
 		}
 		return nil, errors.New("Cannot connect to node: " + nodes[0])
 	}

pkg/storage/donut/donutdriver_test.go

@@ -8,6 +8,7 @@ import (
 	"io"
 	"io/ioutil"
 	"os"
+	"time"
 )
 
 func Test(t *testing.T) { TestingT(t) }
@@ -162,6 +163,11 @@ func (s *MySuite) TestNewObjectCanBeWritten(c *C) {
 
 	actualMetadata, err := donut.GetObjectMetadata("foo", "obj")
 	c.Assert(err, IsNil)
+	expectedMetadata["sys.md5"] = "b10a8db164e0754105b7a99be72e3fe5"
+	expectedMetadata["sys.size"] = "11"
+	_, err = time.Parse(time.RFC3339Nano, actualMetadata["sys.created"])
+	c.Assert(err, IsNil)
+	expectedMetadata["sys.created"] = actualMetadata["sys.created"]
 	c.Assert(actualMetadata, DeepEquals, expectedMetadata)
 }
 

pkg/storage/donut/donutwriter.go

@@ -8,7 +8,7 @@ import (
 )
 
 func newDonutFileWriter(objectDir string) (Writer, error) {
-	dataFile, err := os.OpenFile(path.Join(objectDir, "data"), os.O_WRONLY|os.O_CREATE|os.O_TRUNC|os.O_EXCL, 0600)
+	dataFile, err := os.OpenFile(path.Join(objectDir, "data"), os.O_WRONLY|os.O_CREATE|os.O_EXCL, 0600)
 	if err != nil {
 		return nil, err
 	}

pkg/storage/donut/erasure.go

@@ -17,7 +17,7 @@ import (
 func erasureReader(readers []io.ReadCloser, donutMetadata map[string]string, writer *io.PipeWriter) {
 	// TODO handle errors
 	totalChunks, _ := strconv.Atoi(donutMetadata["chunkCount"])
-	totalLeft, _ := strconv.Atoi(donutMetadata["totalLength"])
+	totalLeft, _ := strconv.Atoi(donutMetadata["size"])
 	blockSize, _ := strconv.Atoi(donutMetadata["blockSize"])
 	k, _ := strconv.Atoi(donutMetadata["erasureK"])
 	m, _ := strconv.Atoi(donutMetadata["erasureM"])
@@ -110,7 +110,7 @@ func erasureGoroutine(r *io.PipeReader, eWriter erasureWriter, isClosed chan<- b
 	metadata["erasureM"] = "8"
 	metadata["erasureTechnique"] = "Cauchy"
 	metadata["md5"] = hex.EncodeToString(dataMd5sum)
-	metadata["totalLength"] = strconv.Itoa(totalLength)
+	metadata["size"] = strconv.Itoa(totalLength)
 	for _, nodeWriter := range eWriter.writers {
 		if nodeWriter != nil {
 			nodeWriter.SetMetadata(eWriter.metadata)

pkg/storage/donut/local.go

@@ -16,6 +16,11 @@ 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) {
 	return nil, errors.New("Not Implemented")
 }