etcdserver/api/v3rpc: debug user cancellation and log warning for rest

The context error with cancel code is typically for user cancellation which
should be at debug level. For other error codes we should display a warning.

Fixes #9085

etcdserver/api/v3rpc/lease.go

@@ -107,7 +107,11 @@ func (ls *LeaseServer) leaseKeepAlive(stream pb.Lease_LeaseKeepAliveServer) erro
 			return nil
 		}
 		if err != nil {
-			plog.Debugf("failed to receive lease keepalive request from gRPC stream (%q)", err.Error())
+			if isClientCtxErr(stream.Context().Err(), err) {
+				plog.Debugf("failed to receive lease keepalive request from gRPC stream (%q)", err.Error())
+			} else {
+				plog.Warningf("failed to receive lease keepalive request from gRPC stream (%q)", err.Error())
+			}
 			return err
 		}
 
@@ -133,7 +137,11 @@ func (ls *LeaseServer) leaseKeepAlive(stream pb.Lease_LeaseKeepAliveServer) erro
 		resp.TTL = ttl
 		err = stream.Send(resp)
 		if err != nil {
-			plog.Debugf("failed to send lease keepalive response to gRPC stream (%q)", err.Error())
+			if isClientCtxErr(stream.Context().Err(), err) {
+				plog.Debugf("failed to send lease keepalive response to gRPC stream (%q)", err.Error())
+			} else {
+				plog.Warningf("failed to send lease keepalive response to gRPC stream (%q)", err.Error())
+			}
 			return err
 		}
 	}

etcdserver/api/v3rpc/util.go

@@ -81,3 +81,16 @@ func togRPCError(err error) error {
 	}
 	return grpcErr
 }
+
+func isClientCtxErr(ctxErr error, err error) bool {
+	if ctxErr != nil {
+		return true
+	}
+
+	ev, ok := status.FromError(err)
+	if !ok {
+		return false
+	}
+	code := ev.Code()
+	return code == codes.Canceled || code == codes.DeadlineExceeded
+}

etcdserver/api/v3rpc/watch.go

@@ -140,7 +140,11 @@ func (ws *watchServer) Watch(stream pb.Watch_WatchServer) (err error) {
 	// deadlock when calling sws.close().
 	go func() {
 		if rerr := sws.recvLoop(); rerr != nil {
-			plog.Debugf("failed to receive watch request from gRPC stream (%q)", rerr.Error())
+			if isClientCtxErr(stream.Context().Err(), rerr) {
+				plog.Debugf("failed to receive watch request from gRPC stream (%q)", rerr.Error())
+			} else {
+				plog.Warningf("failed to receive watch request from gRPC stream (%q)", rerr.Error())
+			}
 			errc <- rerr
 		}
 	}()
@@ -339,7 +343,11 @@ func (sws *serverWatchStream) sendLoop() {
 
 			mvcc.ReportEventReceived(len(evs))
 			if err := sws.gRPCStream.Send(wr); err != nil {
-				plog.Debugf("failed to send watch response to gRPC stream (%q)", err.Error())
+				if isClientCtxErr(sws.gRPCStream.Context().Err(), err) {
+					plog.Debugf("failed to send watch response to gRPC stream (%q)", err.Error())
+				} else {
+					plog.Warningf("failed to send watch response to gRPC stream (%q)", err.Error())
+				}
 				return
 			}
 
@@ -356,7 +364,11 @@ func (sws *serverWatchStream) sendLoop() {
 			}
 
 			if err := sws.gRPCStream.Send(c); err != nil {
-				plog.Debugf("failed to send watch control response to gRPC stream (%q)", err.Error())
+				if isClientCtxErr(sws.gRPCStream.Context().Err(), err) {
+					plog.Debugf("failed to send watch control response to gRPC stream (%q)", err.Error())
+				} else {
+					plog.Warningf("failed to send watch control response to gRPC stream (%q)", err.Error())
+				}
 				return
 			}
 
@@ -372,7 +384,11 @@ func (sws *serverWatchStream) sendLoop() {
 				for _, v := range pending[wid] {
 					mvcc.ReportEventReceived(len(v.Events))
 					if err := sws.gRPCStream.Send(v); err != nil {
-						plog.Debugf("failed to send pending watch response to gRPC stream (%q)", err.Error())
+						if isClientCtxErr(sws.gRPCStream.Context().Err(), err) {
+							plog.Debugf("failed to send pending watch response to gRPC stream (%q)", err.Error())
+						} else {
+							plog.Warningf("failed to send pending watch response to gRPC stream (%q)", err.Error())
+						}
 						return
 					}
 				}