traefik/vendor/github.com/uber/jaeger-client-go/utils/udp_client.go
2018-08-01 13:52:03 +02:00

98 lines
3.1 KiB
Go

// Copyright (c) 2017 Uber Technologies, Inc.
//
// 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 (
"errors"
"fmt"
"io"
"net"
"github.com/uber/jaeger-client-go/thrift"
"github.com/uber/jaeger-client-go/thrift-gen/agent"
"github.com/uber/jaeger-client-go/thrift-gen/jaeger"
"github.com/uber/jaeger-client-go/thrift-gen/zipkincore"
)
// UDPPacketMaxLength is the max size of UDP packet we want to send, synced with jaeger-agent
const UDPPacketMaxLength = 65000
// AgentClientUDP is a UDP client to Jaeger agent that implements agent.Agent interface.
type AgentClientUDP struct {
agent.Agent
io.Closer
connUDP *net.UDPConn
client *agent.AgentClient
maxPacketSize int // max size of datagram in bytes
thriftBuffer *thrift.TMemoryBuffer // buffer used to calculate byte size of a span
}
// NewAgentClientUDP creates a client that sends spans to Jaeger Agent over UDP.
func NewAgentClientUDP(hostPort string, maxPacketSize int) (*AgentClientUDP, error) {
if maxPacketSize == 0 {
maxPacketSize = UDPPacketMaxLength
}
thriftBuffer := thrift.NewTMemoryBufferLen(maxPacketSize)
protocolFactory := thrift.NewTCompactProtocolFactory()
client := agent.NewAgentClientFactory(thriftBuffer, protocolFactory)
destAddr, err := net.ResolveUDPAddr("udp", hostPort)
if err != nil {
return nil, err
}
connUDP, err := net.DialUDP(destAddr.Network(), nil, destAddr)
if err != nil {
return nil, err
}
if err := connUDP.SetWriteBuffer(maxPacketSize); err != nil {
return nil, err
}
clientUDP := &AgentClientUDP{
connUDP: connUDP,
client: client,
maxPacketSize: maxPacketSize,
thriftBuffer: thriftBuffer}
return clientUDP, nil
}
// EmitZipkinBatch implements EmitZipkinBatch() of Agent interface
func (a *AgentClientUDP) EmitZipkinBatch(spans []*zipkincore.Span) error {
return errors.New("Not implemented")
}
// EmitBatch implements EmitBatch() of Agent interface
func (a *AgentClientUDP) EmitBatch(batch *jaeger.Batch) error {
a.thriftBuffer.Reset()
a.client.SeqId = 0 // we have no need for distinct SeqIds for our one-way UDP messages
if err := a.client.EmitBatch(batch); err != nil {
return err
}
if a.thriftBuffer.Len() > a.maxPacketSize {
return fmt.Errorf("Data does not fit within one UDP packet; size %d, max %d, spans %d",
a.thriftBuffer.Len(), a.maxPacketSize, len(batch.Spans))
}
_, err := a.connUDP.Write(a.thriftBuffer.Bytes())
return err
}
// Close implements Close() of io.Closer and closes the underlying UDP connection.
func (a *AgentClientUDP) Close() error {
return a.connUDP.Close()
}