build(deps): bump github.com/uber/jaeger-client-go

Bumps [github.com/uber/jaeger-client-go](https://github.com/uber/jaeger-client-go) from 2.20.1+incompatible to 2.22.1+incompatible.
- [Release notes](https://github.com/uber/jaeger-client-go/releases)
- [Changelog](https://github.com/jaegertracing/jaeger-client-go/blob/master/CHANGELOG.md)
- [Commits](https://github.com/uber/jaeger-client-go/compare/v2.20.1...v2.22.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>
Signed-off-by: Matthew Heon <mheon@redhat.com>

vendor/github.com/uber/jaeger-client-go/transport_udp.go

@@ -18,8 +18,8 @@ import (
 	"errors"
 	"fmt"
 
+	"github.com/uber/jaeger-client-go/internal/reporterstats"
 	"github.com/uber/jaeger-client-go/thrift"
-
 	j "github.com/uber/jaeger-client-go/thrift-gen/jaeger"
 	"github.com/uber/jaeger-client-go/utils"
 )
@@ -27,12 +27,14 @@ import (
 // Empirically obtained constant for how many bytes in the message are used for envelope.
 // The total datagram size is:
 // sizeof(Span) * numSpans + processByteSize + emitBatchOverhead <= maxPacketSize
-// There is a unit test `TestEmitBatchOverhead` that validates this number.
+//
 // Note that due to the use of Compact Thrift protocol, overhead grows with the number of spans
 // in the batch, because the length of the list is encoded as varint32, as well as SeqId.
-const emitBatchOverhead = 30
+//
+// There is a unit test `TestEmitBatchOverhead` that validates this number, it fails at <68.
+const emitBatchOverhead = 70
 
-var errSpanTooLarge = errors.New("Span is too large")
+var errSpanTooLarge = errors.New("span is too large")
 
 type udpSender struct {
 	client          *utils.AgentClientUDP
@@ -44,9 +46,19 @@ type udpSender struct {
 	thriftProtocol  thrift.TProtocol
 	process         *j.Process
 	processByteSize int
+
+	// reporterStats provides access to stats that are only known to Reporter
+	reporterStats reporterstats.ReporterStats
+
+	// The following counters are always non-negative, but we need to send them in signed i64 Thrift fields,
+	// so we keep them as signed. At 10k QPS, overflow happens in about 300 million years.
+	batchSeqNo           int64
+	tooLargeDroppedSpans int64
+	failedToEmitSpans    int64
 }
 
-// NewUDPTransport creates a reporter that submits spans to jaeger-agent
+// NewUDPTransport creates a reporter that submits spans to jaeger-agent.
+// TODO: (breaking change) move to transport/ package.
 func NewUDPTransport(hostPort string, maxPacketSize int) (Transport, error) {
 	if len(hostPort) == 0 {
 		hostPort = fmt.Sprintf("%s:%d", DefaultUDPSpanServerHost, DefaultUDPSpanServerPort)
@@ -66,17 +78,22 @@ func NewUDPTransport(hostPort string, maxPacketSize int) (Transport, error) {
 		return nil, err
 	}
 
-	sender := &udpSender{
+	return &udpSender{
 		client:         client,
 		maxSpanBytes:   maxPacketSize - emitBatchOverhead,
 		thriftBuffer:   thriftBuffer,
-		thriftProtocol: thriftProtocol}
-	return sender, nil
+		thriftProtocol: thriftProtocol,
+	}, nil
+}
+
+// SetReporterStats implements reporterstats.Receiver.
+func (s *udpSender) SetReporterStats(rs reporterstats.ReporterStats) {
+	s.reporterStats = rs
 }
 
 func (s *udpSender) calcSizeOfSerializedThrift(thriftStruct thrift.TStruct) int {
 	s.thriftBuffer.Reset()
-	thriftStruct.Write(s.thriftProtocol)
+	_ = thriftStruct.Write(s.thriftProtocol)
 	return s.thriftBuffer.Len()
 }
 
@@ -89,6 +106,7 @@ func (s *udpSender) Append(span *Span) (int, error) {
 	jSpan := BuildJaegerThrift(span)
 	spanSize := s.calcSizeOfSerializedThrift(jSpan)
 	if spanSize > s.maxSpanBytes {
+		s.tooLargeDroppedSpans++
 		return 1, errSpanTooLarge
 	}
 
@@ -112,9 +130,18 @@ func (s *udpSender) Flush() (int, error) {
 	if n == 0 {
 		return 0, nil
 	}
-	err := s.client.EmitBatch(&j.Batch{Process: s.process, Spans: s.spanBuffer})
+	s.batchSeqNo++
+	batchSeqNo := int64(s.batchSeqNo)
+	err := s.client.EmitBatch(&j.Batch{
+		Process: s.process,
+		Spans:   s.spanBuffer,
+		SeqNo:   &batchSeqNo,
+		Stats:   s.makeStats(),
+	})
 	s.resetBuffers()
-
+	if err != nil {
+		s.failedToEmitSpans += int64(n)
+	}
 	return n, err
 }
 
@@ -129,3 +156,15 @@ func (s *udpSender) resetBuffers() {
 	s.spanBuffer = s.spanBuffer[:0]
 	s.byteBufferSize = s.processByteSize
 }
+
+func (s *udpSender) makeStats() *j.ClientStats {
+	var dropped int64
+	if s.reporterStats != nil {
+		dropped = s.reporterStats.SpansDroppedFromQueue()
+	}
+	return &j.ClientStats{
+		FullQueueDroppedSpans: dropped,
+		TooLargeDroppedSpans:  s.tooLargeDroppedSpans,
+		FailedToEmitSpans:     s.failedToEmitSpans,
+	}
+}