package pb import ( "context" "fmt" "github.com/chrislusf/seaweedfs/weed/glog" "github.com/chrislusf/seaweedfs/weed/pb/filer_pb" "google.golang.org/grpc" "io" "time" ) type ProcessMetadataFunc func(resp *filer_pb.SubscribeMetadataResponse) error func FollowMetadata(filerAddress string, grpcDialOption grpc.DialOption, clientName string, pathPrefix string, additionalPathPrefixes []string, lastTsNs int64, selfSignature int32, processEventFn ProcessMetadataFunc, fatalOnError bool) error { err := WithFilerClient(filerAddress, grpcDialOption, makeFunc(clientName, pathPrefix, additionalPathPrefixes, lastTsNs, selfSignature, processEventFn, fatalOnError)) if err != nil { return fmt.Errorf("subscribing filer meta change: %v", err) } return err } func WithFilerClientFollowMetadata(filerClient filer_pb.FilerClient, clientName string, pathPrefix string, lastTsNs int64, selfSignature int32, processEventFn ProcessMetadataFunc, fatalOnError bool) error { err := filerClient.WithFilerClient(makeFunc(clientName, pathPrefix, nil, lastTsNs, selfSignature, processEventFn, fatalOnError)) if err != nil { return fmt.Errorf("subscribing filer meta change: %v", err) } return nil } func makeFunc(clientName string, pathPrefix string, additionalPathPrefixes []string, lastTsNs int64, selfSignature int32, processEventFn ProcessMetadataFunc, fatalOnError bool) func(client filer_pb.SeaweedFilerClient) error { return func(client filer_pb.SeaweedFilerClient) error { ctx, cancel := context.WithCancel(context.Background()) defer cancel() stream, err := client.SubscribeMetadata(ctx, &filer_pb.SubscribeMetadataRequest{ ClientName: clientName, PathPrefix: pathPrefix, PathPrefixes: additionalPathPrefixes, SinceNs: lastTsNs, Signature: selfSignature, }) if err != nil { return fmt.Errorf("subscribe: %v", err) } for { resp, listenErr := stream.Recv() if listenErr == io.EOF { return nil } if listenErr != nil { return listenErr } if err := processEventFn(resp); err != nil { if fatalOnError { glog.Fatalf("process %v: %v", resp, err) } else { glog.Errorf("process %v: %v", resp, err) } } lastTsNs = resp.TsNs } } } func AddOffsetFunc(processEventFn ProcessMetadataFunc, offsetInterval time.Duration, offsetFunc func(counter int64, offset int64) error) ProcessMetadataFunc { var counter int64 var lastWriteTime time.Time return func(resp *filer_pb.SubscribeMetadataResponse) error { if err := processEventFn(resp); err != nil { return err } counter++ if lastWriteTime.Add(offsetInterval).Before(time.Now()) { counter = 0 lastWriteTime = time.Now() if err := offsetFunc(counter, resp.TsNs); err != nil { return err } } return nil } }