refactor client subscribe metadata

weed/filesys/meta_cache/meta_cache_subscribe.go

@@ -2,12 +2,9 @@ package meta_cache
 
 import (
 	"context"
-	"fmt"
-	"io"
-	"time"
-
 	"github.com/chrislusf/seaweedfs/weed/filer"
 	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/pb"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 	"github.com/chrislusf/seaweedfs/weed/util"
 )
@@ -62,38 +59,8 @@ func SubscribeMetaEvents(mc *MetaCache, selfSignature int32, client filer_pb.Fil
 
 	}
 
-	for {
-		err := client.WithFilerClient(func(client filer_pb.SeaweedFilerClient) error {
-			ctx, cancel := context.WithCancel(context.Background())
-			defer cancel()
-			stream, err := client.SubscribeMetadata(ctx, &filer_pb.SubscribeMetadataRequest{
-				ClientName: "mount",
-				PathPrefix: dir,
-				SinceNs:    lastTsNs,
-				Signature:  selfSignature,
-			})
-			if err != nil {
-				return fmt.Errorf("subscribe: %v", err)
-			}
+	return util.Retry("followMetaUpdates", func() error {
+		return pb.WithFilerClientFollowMetadata(client, "mount", dir, lastTsNs, selfSignature, processEventFn, true)
+	})
 
-			for {
-				resp, listenErr := stream.Recv()
-				if listenErr == io.EOF {
-					return nil
-				}
-				if listenErr != nil {
-					return listenErr
-				}
-
-				if err := processEventFn(resp); err != nil {
-					glog.Fatalf("process %v: %v", resp, err)
-				}
-				lastTsNs = resp.TsNs
-			}
-		})
-		if err != nil {
-			glog.Errorf("subscribing filer meta change: %v", err)
-		}
-		time.Sleep(time.Second)
-	}
 }