gRPC migration update
Change-Id: Icdd1a824948fa994cd36bd121c962f5ecf74e3cf
diff --git a/vendor/github.com/uber/jaeger-client-go/utils/reconnecting_udp_conn.go b/vendor/github.com/uber/jaeger-client-go/utils/reconnecting_udp_conn.go
new file mode 100644
index 0000000..0dffc7f
--- /dev/null
+++ b/vendor/github.com/uber/jaeger-client-go/utils/reconnecting_udp_conn.go
@@ -0,0 +1,189 @@
+// Copyright (c) 2020 The Jaeger Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package utils
+
+import (
+ "fmt"
+ "net"
+ "sync"
+ "sync/atomic"
+ "time"
+
+ "github.com/uber/jaeger-client-go/log"
+)
+
+// reconnectingUDPConn is an implementation of udpConn that resolves hostPort every resolveTimeout, if the resolved address is
+// different than the current conn then the new address is dialed and the conn is swapped.
+type reconnectingUDPConn struct {
+ hostPort string
+ resolveFunc resolveFunc
+ dialFunc dialFunc
+ logger log.Logger
+ bufferBytes int64
+
+ connMtx sync.RWMutex
+ conn *net.UDPConn
+ destAddr *net.UDPAddr
+ closeChan chan struct{}
+}
+
+type resolveFunc func(network string, hostPort string) (*net.UDPAddr, error)
+type dialFunc func(network string, laddr, raddr *net.UDPAddr) (*net.UDPConn, error)
+
+// newReconnectingUDPConn returns a new udpConn that resolves hostPort every resolveTimeout, if the resolved address is
+// different than the current conn then the new address is dialed and the conn is swapped.
+func newReconnectingUDPConn(hostPort string, resolveTimeout time.Duration, resolveFunc resolveFunc, dialFunc dialFunc, logger log.Logger) (*reconnectingUDPConn, error) {
+ conn := &reconnectingUDPConn{
+ hostPort: hostPort,
+ resolveFunc: resolveFunc,
+ dialFunc: dialFunc,
+ logger: logger,
+ closeChan: make(chan struct{}),
+ }
+
+ if err := conn.attemptResolveAndDial(); err != nil {
+ logger.Error(fmt.Sprintf("failed resolving destination address on connection startup, with err: %q. retrying in %s", err.Error(), resolveTimeout))
+ }
+
+ go conn.reconnectLoop(resolveTimeout)
+
+ return conn, nil
+}
+
+func (c *reconnectingUDPConn) reconnectLoop(resolveTimeout time.Duration) {
+ ticker := time.NewTicker(resolveTimeout)
+ defer ticker.Stop()
+
+ for {
+ select {
+ case <-c.closeChan:
+ return
+ case <-ticker.C:
+ if err := c.attemptResolveAndDial(); err != nil {
+ c.logger.Error(err.Error())
+ }
+ }
+ }
+}
+
+func (c *reconnectingUDPConn) attemptResolveAndDial() error {
+ newAddr, err := c.resolveFunc("udp", c.hostPort)
+ if err != nil {
+ return fmt.Errorf("failed to resolve new addr for host %q, with err: %w", c.hostPort, err)
+ }
+
+ c.connMtx.RLock()
+ curAddr := c.destAddr
+ c.connMtx.RUnlock()
+
+ // dont attempt dial if an addr was successfully dialed previously and, resolved addr is the same as current conn
+ if curAddr != nil && newAddr.String() == curAddr.String() {
+ return nil
+ }
+
+ if err := c.attemptDialNewAddr(newAddr); err != nil {
+ return fmt.Errorf("failed to dial newly resolved addr '%s', with err: %w", newAddr, err)
+ }
+
+ return nil
+}
+
+func (c *reconnectingUDPConn) attemptDialNewAddr(newAddr *net.UDPAddr) error {
+ connUDP, err := c.dialFunc(newAddr.Network(), nil, newAddr)
+ if err != nil {
+ return err
+ }
+
+ if bufferBytes := int(atomic.LoadInt64(&c.bufferBytes)); bufferBytes != 0 {
+ if err = connUDP.SetWriteBuffer(bufferBytes); err != nil {
+ return err
+ }
+ }
+
+ c.connMtx.Lock()
+ c.destAddr = newAddr
+ // store prev to close later
+ prevConn := c.conn
+ c.conn = connUDP
+ c.connMtx.Unlock()
+
+ if prevConn != nil {
+ return prevConn.Close()
+ }
+
+ return nil
+}
+
+// Write calls net.udpConn.Write, if it fails an attempt is made to connect to a new addr, if that succeeds the write is retried before returning
+func (c *reconnectingUDPConn) Write(b []byte) (int, error) {
+ var bytesWritten int
+ var err error
+
+ c.connMtx.RLock()
+ if c.conn == nil {
+ // if connection is not initialized indicate this with err in order to hook into retry logic
+ err = fmt.Errorf("UDP connection not yet initialized, an address has not been resolved")
+ } else {
+ bytesWritten, err = c.conn.Write(b)
+ }
+ c.connMtx.RUnlock()
+
+ if err == nil {
+ return bytesWritten, nil
+ }
+
+ // attempt to resolve and dial new address in case that's the problem, if resolve and dial succeeds, try write again
+ if reconnErr := c.attemptResolveAndDial(); reconnErr == nil {
+ c.connMtx.RLock()
+ defer c.connMtx.RUnlock()
+ return c.conn.Write(b)
+ }
+
+ // return original error if reconn fails
+ return bytesWritten, err
+}
+
+// Close stops the reconnectLoop, then closes the connection via net.udpConn 's implementation
+func (c *reconnectingUDPConn) Close() error {
+ close(c.closeChan)
+
+ // acquire rw lock before closing conn to ensure calls to Write drain
+ c.connMtx.Lock()
+ defer c.connMtx.Unlock()
+
+ if c.conn != nil {
+ return c.conn.Close()
+ }
+
+ return nil
+}
+
+// SetWriteBuffer defers to the net.udpConn SetWriteBuffer implementation wrapped with a RLock. if no conn is currently held
+// and SetWriteBuffer is called store bufferBytes to be set for new conns
+func (c *reconnectingUDPConn) SetWriteBuffer(bytes int) error {
+ var err error
+
+ c.connMtx.RLock()
+ if c.conn != nil {
+ err = c.conn.SetWriteBuffer(bytes)
+ }
+ c.connMtx.RUnlock()
+
+ if err == nil {
+ atomic.StoreInt64(&c.bufferBytes, int64(bytes))
+ }
+
+ return err
+}