handle DryRun send size estimate errors with bookmarks

replication/fsrep/fsfsm.go

@@ -59,7 +59,7 @@ type StepReport struct {
 	Status   StepState
 	Problem  string
 	Bytes    int64
-	ExpectedBytes int64
+	ExpectedBytes int64 // 0 means no size estimate possible
 }
 
 type Report struct {
@@ -185,7 +185,7 @@ type ReplicationStep struct {
 	err error
 
 	byteCounter  *util.ByteCounterReader
-	expectedSize int64
+	expectedSize int64 // 0 means no size estimate present / possible
 }
 
 func (f *Replication) TakeStep(ctx context.Context, sender Sender, receiver Receiver) (post State, nextStepDate time.Time) {
@@ -457,6 +457,7 @@ func (s *ReplicationStep) updateSizeEstimate(ctx context.Context, sender Sender)
 	sres, _, err := sender.Send(ctx, sr)
 	if err != nil {
 		log.WithError(err).Error("dry run send request failed")
+		return err
 	}
 	s.expectedSize = sres.ExpectedSize
 	return nil

replication/pdu/pdu.pb.go

@@ -493,7 +493,8 @@ func (m *Property) GetValue() string {
 type SendRes struct {
 	// Whether the resume token provided in the request has been used or not.
 	UsedResumeToken bool `protobuf:"varint,1,opt,name=UsedResumeToken,proto3" json:"UsedResumeToken,omitempty"`
-	// Expected stream size determined by dry run, not exact
+	// Expected stream size determined by dry run, not exact.
+	// 0 indicates that for the given SendReq, no size estimate could be made.
 	ExpectedSize         int64       `protobuf:"varint,2,opt,name=ExpectedSize,proto3" json:"ExpectedSize,omitempty"`
 	Properties           []*Property `protobuf:"bytes,3,rep,name=Properties,proto3" json:"Properties,omitempty"`
 	XXX_NoUnkeyedLiteral struct{}    `json:"-"`

replication/pdu/pdu.proto

@@ -65,7 +65,8 @@ message SendRes {
     // Whether the resume token provided in the request has been used or not.
     bool UsedResumeToken = 1;
 
-    // Expected stream size determined by dry run, not exact
+    // Expected stream size determined by dry run, not exact.
+    // 0 indicates that for the given SendReq, no size estimate could be made.
     int64 ExpectedSize = 2;
 
     repeated Property Properties = 3;