periodic scripts exeuction from leader master

weed/filer2/stream.go

@@ -0,0 +1,41 @@
+package filer2
+
+import (
+	"io"
+
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"github.com/chrislusf/seaweedfs/weed/util"
+	"github.com/chrislusf/seaweedfs/weed/wdclient"
+)
+
+func StreamContent(masterClient *wdclient.MasterClient, w io.Writer, chunks []*filer_pb.FileChunk, offset int64, size int) error {
+
+	chunkViews := ViewFromChunks(chunks, offset, size)
+
+	fileId2Url := make(map[string]string)
+
+	for _, chunkView := range chunkViews {
+
+		urlString, err := masterClient.LookupFileId(chunkView.FileId)
+		if err != nil {
+			glog.V(1).Infof("operation LookupFileId %s failed, err: %v", chunkView.FileId, err)
+			return err
+		}
+		fileId2Url[chunkView.FileId] = urlString
+	}
+
+	for _, chunkView := range chunkViews {
+		urlString := fileId2Url[chunkView.FileId]
+		_, err := util.ReadUrlAsStream(urlString, chunkView.Offset, int(chunkView.Size), func(data []byte) {
+			w.Write(data)
+		})
+		if err != nil {
+			glog.V(1).Infof("read %s failed, err: %v", chunkView.FileId, err)
+			return err
+		}
+	}
+
+	return nil
+
+}