// 获取下一个active状态的BackendConn
func (s *BackServiceLB) nextBackendConn() *BackendConnLB {
s.activeConnsLock.Lock()
defer s.activeConnsLock.Unlock()
// TODO: 暂时采用RoundRobin的方法，可以采用其他具有优先级排列的方法
var backSocket *BackendConnLB
if len(s.activeConns) == 0 {
if s.verbose {
log.Printf(Cyan("[%s]ActiveConns Len 0"), s.serviceName)
}
backSocket = nil
} else {
if s.currentConnIndex >= len(s.activeConns) {
s.currentConnIndex = 0
}
backSocket = s.activeConns[s.currentConnIndex]
s.currentConnIndex++
if s.verbose {
log.Printf(Cyan("[%s]ActiveConns Len %d, CurrentIndex: %d"), s.serviceName,
len(s.activeConns), s.currentConnIndex)
}
}
return backSocket
}
// 处理所有的等待中的请求
func (bc *BackendConn) flushRequests(err error) {
// 告诉BackendService, 不再接受新的请求
bc.MarkConnActiveFalse()
bc.Lock()
seqRequest := bc.seqNum2Request
bc.seqNum2Request = make(map[int32]*Request, 4096)
bc.Unlock()
threshold := time.Now().Add(-time.Second * 5)
for _, request := range seqRequest {
if request.Start > 0 {
t := time.Unix(request.Start, 0)
if t.After(threshold) {
// 似乎在笔记本上，合上显示器之后出出现网络错误
log.Printf(Red("[%s]Handle Failed Request: %s, Started: %s"),
request.Service, request.Request.Name, FormatYYYYmmDDHHMMSS(t))
}
} else {
log.Printf(Red("[%s]Handle Failed Request: %s"), request.Service,
request.Request.Name)
}
request.Response.Err = err
if request.Wait != nil {
request.Wait.Done()
}
}
}
// 配对 Request, resp, err
// PARAM: resp []byte 为一帧完整的thrift数据包
func (bc *BackendConn) setResponse(r *Request, data []byte, err error) error {
// 表示出现错误了
if data == nil {
log.Printf("[%s]No Data From Server, error: %v", r.Service, err)
r.Response.Err = err
} else {
// 从resp中读取基本的信息
typeId, seqId, err := DecodeThriftTypIdSeqId(data)
// 解码错误，直接报错
if err != nil {
return err
}
// 找到对应的Request
bc.Lock()
req, ok := bc.seqNum2Request[seqId]
if ok {
delete(bc.seqNum2Request, seqId)
}
bc.Unlock()
// 如果是心跳，则OK
if typeId == MESSAGE_TYPE_HEART_BEAT {
// log.Printf(Magenta("Get Ping/Pang Back"))
bc.hbLastTime.Set(time.Now().Unix())
return nil
}
if !ok {
return errors.New("Invalid Response")
}
if bc.verbose {
log.Printf("[%s]Data From Server, seqId: %d, Request: %d", req.Service, seqId, req.Request.SeqId)
}
r = req
r.Response.TypeId = typeId
}
r.Response.Data, r.Response.Err = data, err
// 还原SeqId
if data != nil {
r.RestoreSeqId()
}
// 设置几个控制用的channel
if err != nil && r.Failed != nil {
r.Failed.Set(true)
}
if r.Wait != nil {
r.Wait.Done()
}
return err
}
func (p *fakeServer) Dispatch(r *Request) error {
log.Printf("Request SeqId: %d, MethodName: %s\n", r.Request.SeqId, r.Request.Name)
r.Wait.Add(1)
go func() {
time.Sleep(time.Millisecond)
r.Response.Data = []byte(string(r.Request.Data))
typeId, seqId, _ := DecodeThriftTypIdSeqId(r.Response.Data)
log.Printf(Green("TypeId: %d, SeqId: %d\n"), typeId, seqId)
r.Wait.Done()
}()
// r.RestoreSeqId()
// r.Wait.Done()
return nil
}
//
// 不断建立到后端的逻辑，负责: BackendConn#input到redis的数据的输入和返回
//
func (bc *BackendConn) Run() {
for k := 0; !bc.IsMarkOffline.Get(); k++ {
// 1. 首先BackendConn将当前 input中的数据写到后端服务中
transport, err := bc.ensureConn()
if err != nil {
log.ErrorErrorf(err, "[%s]BackendConn#ensureConn error: %v", bc.service, err)
return
}
c := NewTBufferedFramedTransport(transport, 100*time.Microsecond, 20)
// 2. 将 bc.input 中的请求写入 后端的Rpc Server
err = bc.loopWriter(c) // 同步
// 3. 停止接受Request
bc.MarkConnActiveFalse()
// 4. 将bc.input中剩余的 Request直接出错处理
if err == nil {
log.Printf(Red("[%s]BackendConn#loopWriter normal Exit..."), bc.service)
break
} else {
// 对于尚未处理的Request, 直接报错
for i := len(bc.input); i != 0; i-- {
r := <-bc.input
bc.setResponse(r, nil, err)
}
}
}
}
// 处理所有的等待中的请求
func (bc *BackendConnLB) flushRequests(err error) {
// 告诉BackendService, 不再接受新的请求
bc.MarkConnActiveFalse()
bc.Lock()
seqRequest := bc.seqNum2Request
bc.seqNum2Request = make(map[int32]*Request)
bc.Unlock()
for _, request := range seqRequest {
if request.Request.TypeId == MESSAGE_TYPE_HEART_BEAT {
// 心跳出错了，则直接直接跳过
} else {
log.Printf(Red("Handle Failed Request: %s.%s"), request.Service, request.Request.Name)
request.Response.Err = err
if request.Wait != nil {
request.Wait.Done()
}
}
}
// 关闭输入
close(bc.input)
}
//
// 后端如何处理一个Request, 处理完毕之后直接返回，因为Caller已经做好异步处理了
//
func (s *BackServiceLB) Dispatch(r *Request) error {
backendConn := s.nextBackendConn()
r.Service = s.serviceName
if backendConn == nil {
// 没有后端服务
if s.verbose {
log.Printf(Red("[%s]No BackSocket Found: %s"),
s.serviceName, r.Request.Name)
}
// 从errMsg来构建异常
errMsg := GetWorkerNotFoundData(r, "BackServiceLB")
// log.Printf(Magenta("---->Convert Error Back to Exception:[%d] %s\n"), len(errMsg), string(errMsg))
r.Response.Data = errMsg
return nil
} else {
// if s.verbose {
// log.Println("SendMessage With: ", backendConn.Addr4Log(), "For Service: ", s.serviceName)
// }
backendConn.PushBack(r)
r.Wait.Wait()
return nil
}
}
func (s *Session) loopWriter(tasks <-chan *Request) error {
// Proxy: Session ---> Client
for r := range tasks {
// 1. 等待Request对应的Response
// 出错了如何处理呢?
s.handleResponse(r)
// 2. 将结果写回给Client
if s.verbose {
log.Printf("[%s]Session#loopWriter --> client FrameSize: %d",
r.Service, len(r.Response.Data))
}
// r.Response.Data ---> Client
_, err := s.TBufferedFramedTransport.Write(r.Response.Data)
if err != nil {
log.ErrorErrorf(err, "Write back Data Error: %v", err)
return err
}
// 3. Flush
err = s.TBufferedFramedTransport.FlushBuffer(true) // len(tasks) == 0
if err != nil {
log.ErrorErrorf(err, "Write back Data Error: %v", err)
return err
}
r.Recycle()
}
return nil
}
// 配对 Request, resp, err
// PARAM: resp []byte 为一帧完整的thrift数据包
func (bc *BackendConnLB) setResponse(r *Request, data []byte, err error) error {
// 表示出现错误了
if data == nil {
log.Printf("No Data From Server, error: %v\n", err)
r.Response.Err = err
} else {
// 从resp中读取基本的信息
typeId, seqId, err := DecodeThriftTypIdSeqId(data)
// 解码错误，直接报错
if err != nil {
return err
}
if typeId == MESSAGE_TYPE_STOP {
// 不再接受新的输入
// 直接来自后端的服务(不遵循: Request/Reply模型)
bc.MarkConnActiveFalse()
return nil
}
// 找到对应的Request
bc.Lock()
req, ok := bc.seqNum2Request[seqId]
if ok {
delete(bc.seqNum2Request, seqId)
}
bc.Unlock()
// 如果是心跳，则OK
if typeId == MESSAGE_TYPE_HEART_BEAT {
bc.hbLastTime.Set(time.Now().Unix())
return nil
}
if !ok {
return errors.New("Invalid Response")
}
// log.Printf("Data From Server, seqId: %d, Request: %d\n", seqId, req.Request.SeqId)
r = req
r.Response.TypeId = typeId
}
r.Response.Data, r.Response.Err = data, err
// 还原SeqId
if data != nil {
r.RestoreSeqId()
}
// 设置几个控制用的channel
if err != nil && r.Failed != nil {
r.Failed.Set(true)
}
if r.Wait != nil {
r.Wait.Done()
}
return err
}
//
// 确保Socket成功连接到后端服务器
//
func (bc *BackendConn) ensureConn() (transport thrift.TTransport, err error) {
// 1. 创建连接(只要IP没有问题， err一般就是空)
timeout := time.Second * 5
if strings.Contains(bc.addr, ":") {
transport, err = thrift.NewTSocketTimeout(bc.addr, timeout)
} else {
transport, err = NewTUnixDomainTimeout(bc.addr, timeout)
}
log.Printf(Cyan("[%s]Create Socket To: %s"), bc.service, bc.addr)
if err != nil {
log.ErrorErrorf(err, "[%s]Create Socket Failed: %v, Addr: %s", err, bc.service, bc.addr)
// 连接不上，失败
return nil, err
}
// 2. 只要服务存在，一般不会出现err
sleepInterval := 1
err = transport.Open()
for err != nil && !bc.IsMarkOffline.Get() {
log.ErrorErrorf(err, "[%s]Socket Open Failed: %v, Addr: %s", bc.service, err, bc.addr)
// Sleep: 1, 2, 4这几个间隔
time.Sleep(time.Duration(sleepInterval) * time.Second)
if sleepInterval < 4 {
sleepInterval *= 2
}
err = transport.Open()
}
return transport, err
}
//
// 两参数是必须的: ProductName, zkAddress, frontAddr可以用来测试
//
func (p *ProxyServer) Run() {
var transport thrift.TServerTransport
var err error
log.Printf(Magenta("Start Proxy at Address: %s"), p.proxyAddr)
// 读取后端服务的配置
isUnixDomain := false
if !strings.Contains(p.proxyAddr, ":") {
if FileExist(p.proxyAddr) {
os.Remove(p.proxyAddr)
}
transport, err = NewTServerUnixDomain(p.proxyAddr)
isUnixDomain = true
} else {
transport, err = thrift.NewTServerSocket(p.proxyAddr)
}
if err != nil {
log.ErrorErrorf(err, "Server Socket Create Failed: %v, Front: %s", err, p.proxyAddr)
}
// 开始监听
// transport.Open()
transport.Listen()
ch := make(chan thrift.TTransport, 4096)
defer close(ch)
go func() {
var address string
for c := range ch {
// 为每个Connection建立一个Session
socket, ok := c.(SocketAddr)
if isUnixDomain {
address = p.proxyAddr
} else if ok {
address = socket.Addr().String()
} else {
address = "unknow"
}
x := NewSession(c, address, p.verbose)
// Session独立处理自己的请求
go x.Serve(p.router, 1000)
}
}()
// Accept什么时候出错，出错之后如何处理呢?
for {
c, err := transport.Accept()
if err != nil {
log.ErrorErrorf(err, "Accept Error: %v", err)
break
} else {
ch <- c
}
}
}
func (s *BackService) StateChanged(conn *BackendConn) {
log.Printf(Cyan("[%s]StateChanged: %s, Index: %d, Count: %d, IsConnActive: %t"),
s.serviceName, conn.addr, conn.Index, len(s.activeConns),
conn.IsConnActive.Get())
s.activeConnsLock.Lock()
defer s.activeConnsLock.Unlock()
if conn.IsConnActive.Get() {
log.Printf(Cyan("[%s]MarkConnActiveOK: %s, Index: %d, Count: %d"),
s.serviceName, conn.addr, conn.Index, len(s.activeConns))
if conn.Index == INVALID_ARRAY_INDEX {
conn.Index = len(s.activeConns)
s.activeConns = append(s.activeConns, conn)
log.Printf(Green("[%s]Add BackendConn to activeConns: %s, Total Actives: %d"),
s.serviceName, conn.Addr(), len(s.activeConns))
}
} else {
log.Printf(Red("[%s]Remove BackendConn From activeConns: %s, Index: %d"),
s.serviceName, conn.Addr(), conn.Index)
if conn.Index != INVALID_ARRAY_INDEX {
lastIndex := len(s.activeConns) - 1
// 将最后一个元素和当前的元素交换位置
if lastIndex != conn.Index {
lastConn := s.activeConns[lastIndex]
s.activeConns[conn.Index] = lastConn
lastConn.Index = conn.Index
}
s.activeConns[lastIndex] = nil
conn.Index = INVALID_ARRAY_INDEX
// slice
s.activeConns = s.activeConns[0:lastIndex]
log.Printf(Red("[%s]Remove BackendConn From activeConns: %s, Remains: %d"),
s.serviceName, conn.Addr(), len(s.activeConns))
}
}
}
//
// MarkOffline发生场景:
// 1. 后端服务即将下线，预先通知
// 2. 后端服务已经挂了，zk检测到
//
// BackendConn 在这里暂时理解关闭conn, 而是从 backend_service_proxy中下线当前的conn,
// 然后conn的关闭根据 心跳&Conn的读写异常来判断; 因此 IsConnActive = false 情况下，心跳不能关闭
//
func (bc *BackendConn) MarkOffline() {
if !bc.IsMarkOffline.Get() {
log.Printf(Magenta("[%s]BackendConn: %s MarkOffline"), bc.service, bc.addr)
bc.IsMarkOffline.Set(true)
// 不再接受(来自backend_service_proxy的)新的输入
bc.MarkConnActiveFalse()
close(bc.input)
}
}
func (bc *BackendConn) MarkConnActiveFalse() {
if bc.IsConnActive.Get() {
log.Printf(Red("[%s]MarkConnActiveFalse: %s, %p"), bc.service, bc.addr, bc.delegate)
// 从Active切换到非正常状态
bc.IsConnActive.Set(false)
if bc.delegate != nil {
bc.delegate.StateChanged(bc) // 通知其他人状态出现问题
}
}
}
// 只有在conn出现错误时才会调用
func (s *BackServiceLB) StateChanged(conn *BackendConnLB) {
s.activeConnsLock.Lock()
defer s.activeConnsLock.Unlock()
log.Printf(Green("[%s]StateChanged: %s, Index: %d, Count: %d"), conn.serviceName, conn.addr4Log, conn.Index, len(s.activeConns))
if conn.IsConnActive.Get() {
// BackServiceLB 只有一个状态转移: Active --> Not Active
log.Printf(Magenta("Unexpected BackendConnLB State"))
if s.verbose {
panic("Unexpected BackendConnLB State")
}
} else {
log.Printf(Red("Remove BackendConn From activeConns: %s, Index: %d, Count: %d"),
conn.Addr4Log(), conn.Index, len(s.activeConns))
// 从数组中删除一个元素(O(1)的操作)
if conn.Index != INVALID_ARRAY_INDEX {
// 1. 和最后一个元素进行交换
lastIndex := len(s.activeConns) - 1
if lastIndex != conn.Index {
lastConn := s.activeConns[lastIndex]
// 将最后一个元素和当前的元素交换位置
s.activeConns[conn.Index] = lastConn
lastConn.Index = conn.Index
// 删除引用
s.activeConns[lastIndex] = nil
conn.Index = INVALID_ARRAY_INDEX
}
log.Printf(Red("Remove BackendConn From activeConns: %s"), conn.Addr4Log())
// 2. slice
s.activeConns = s.activeConns[0:lastIndex]
}
}
}
// run之间 transport刚刚建立，因此服务的可靠性比较高
func (bc *BackendConnLB) Run() {
log.Printf(Green("[%s]Add New BackendConnLB: %s\n"), bc.serviceName, bc.addr4Log)
// 1. 首先BackendConn将当前 input中的数据写到后端服务中
err := bc.loopWriter()
// 2. 从Active切换到非正常状态, 同时不再从backend_service_lb接受新的任务
// 可能出现异常，也可能正常退出(反正不干活了)
bc.MarkConnActiveFalse()
log.Printf(Red("[%s]Remove Faild BackendConnLB: %s\n"), bc.serviceName, bc.addr4Log)
if err == nil {
// bc.input被关闭了，应该就没有 Request 了
} else {
// 如果出现err, 则将bc.input中现有的数据都flush回去（直接报错)
for i := len(bc.input); i != 0; i-- {
r := <-bc.input
bc.setResponse(r, nil, err)
}
}
}
//
//
// 等待Request请求的返回: Session最终被Block住
//
func (s *Session) handleResponse(r *Request) {
// 等待结果的出现
r.Wait.Wait()
// 将Err转换成为Exception
if r.Response.Err != nil {
r.Response.Data = GetThriftException(r, "proxy_session")
log.Printf(Magenta("---->Convert Error Back to Exception"))
}
// 如何处理Data和Err呢?
incrOpStats(r.OpStr, microseconds()-r.Start)
}
// 处理来自Client的请求
func (s *Session) handleRequest(request []byte, d Dispatcher) (*Request, error) {
// 构建Request
if s.verbose {
log.Printf("HandleRequest: %s", string(request))
}
r := NewRequest(request, true)
// 增加统计
s.LastOpUnix = time.Now().Unix()
s.Ops++
// 交给Dispatch
// Router
return r, d.Dispatch(r)
}
//
// 删除过期的Endpoints
//
func (p *BackSockets) PurgeEndpoints() {
// 没有需要删除的对象
if p.Active == len(p.Sockets) {
return
}
log.Printf(utils.Green("PurgeEndpoints %d vs. %d"), p.Active, len(p.Sockets))
p.Lock()
defer p.Unlock()
now := time.Now().Unix()
nowStr := time.Now().Format("@2006-01-02 15:04:05")
for i := p.Active; i < len(p.Sockets); i++ {
// 逐步删除过期的Sockets
current := p.Sockets[i]
lastIndex := len(p.Sockets) - 1
if now-current.markedOfflineTime > 5 {
// 将i和最后一个元素交换
p.swap(current, p.Sockets[lastIndex])
// 关闭
// current
// 关闭旧的Socket
log.Println(utils.Red("PurgeEndpoints#Purge Old Socket: "), current.Addr, nowStr)
// 由Socket自己维护自己的状态
// current.Socket.Close()
p.Sockets[lastIndex] = nil
p.Sockets = p.Sockets[0:lastIndex]
i-- // 保持原位
}
}
}
func NewThriftLoadBalanceServer(config *utils.Config) *ThriftLoadBalanceServer {
log.Printf("FrontAddr: %s\n", Magenta(config.FrontendAddr))
// 前端对接rpc_proxy
p := &ThriftLoadBalanceServer{
config: config,
zkAddr: config.ZkAddr,
productName: config.ProductName,
serviceName: config.Service,
frontendAddr: config.FrontendAddr,
backendAddr: config.BackAddr,
verbose: config.Verbose,
exitEvt: make(chan bool),
}
p.topo = zk.NewTopology(p.productName, p.zkAddr)
p.lbServiceName = GetServiceIdentity(p.frontendAddr)
// 后端对接: 各种python的rpc server
p.backendService = NewBackServiceLB(p.serviceName, p.backendAddr, p.verbose, p.exitEvt)
return p
}
func (s *BackService) Stop() {
// 标志停止
s.stop.Set(true)
// 触发一个事件（之后ServiceNodes也不再监控)
s.evtbus <- true
go func() {
// TODO:
for true {
now := time.Now().Unix()
if now-s.lastRequestTime.Get() > 10 {
break
} else {
time.Sleep(time.Second)
}
}
for len(s.activeConns) > 0 {
s.activeConns[0].MarkOffline()
}
log.Printf(Red("Mark All Connections Off: %s"), s.serviceName)
}()
}
// 创建一个BackService
func NewBackService(productName string, serviceName string, topo *zk.Topology, verbose bool) *BackService {
service := &BackService{
productName: productName,
serviceName: serviceName,
activeConns: make([]*BackendConn, 0, 10),
addr2Conn: make(map[string]*BackendConn),
topo: topo,
verbose: verbose,
}
service.WatchBackServiceNodes()
go func() {
for !service.stop.Get() {
log.Printf(Blue("[Report]: %s --> %d backservice, coroutine: %d"),
service.serviceName, service.Active(), runtime.NumGoroutine())
time.Sleep(time.Second * 10)
}
}()
return service
}
func mainBody(zkAddr string, productName string, serviceName string, frontendAddr string, backendAddr string) {
// 1. 创建到zk的连接
var topo *zk.Topology
topo = zk.NewTopology(productName, zkAddr)
// 2. 启动服务
frontend, _ := zmq.NewSocket(zmq.ROUTER)
backend, _ := zmq.NewSocket(zmq.ROUTER)
defer frontend.Close()
defer backend.Close()
// ROUTER/ROUTER绑定到指定的端口
// tcp://127.0.0.1:5555 --> tcp://127_0_0_1:5555
lbServiceName := GetServiceIdentity(frontendAddr)
frontend.SetIdentity(lbServiceName)
frontend.Bind(frontendAddr) // For clients "tcp://*:5555"
backend.Bind(backendAddr) // For workers "tcp://*:5556"
log.Printf("FrontAddr: %s, BackendAddr: %s\n", magenta(frontendAddr), magenta(backendAddr))
// 后端的workers queue
workersQueue := queue.NewPPQueue()
// 心跳间隔1s
heartbeat_at := time.Tick(HEARTBEAT_INTERVAL)
poller1 := zmq.NewPoller()
poller1.Add(backend, zmq.POLLIN)
poller2 := zmq.NewPoller()
// 前提:
// 1. 当zeromq通知消息可读时，那么整个Message(所有的msg parts)都可读
// 2. 往zeromq写数据时，是异步的，因此也不存在block(除非数据量巨大)
//
poller2.Add(backend, zmq.POLLIN)
poller2.Add(frontend, zmq.POLLIN)
// 3. 注册zk
var endpointInfo map[string]interface{} = make(map[string]interface{})
endpointInfo["frontend"] = frontendAddr
endpointInfo["backend"] = backendAddr
topo.AddServiceEndPoint(serviceName, lbServiceName, endpointInfo)
isAlive := true
isAliveLock := &sync.RWMutex{}
go func() {
servicePath := topo.ProductServicePath(serviceName)
evtbus := make(chan interface{})
for true {
// 只是为了监控状态
_, err := topo.WatchNode(servicePath, evtbus)
if err == nil {
// 等待事件
e := (<-evtbus).(topozk.Event)
if e.State == topozk.StateExpired || e.Type == topozk.EventNotWatching {
// Session过期了，则需要删除之前的数据，因为这个数据的Owner不是当前的Session
topo.DeleteServiceEndPoint(serviceName, lbServiceName)
topo.AddServiceEndPoint(serviceName, lbServiceName, endpointInfo)
}
} else {
time.Sleep(time.Second)
}
isAliveLock.RLock()
isAlive1 := isAlive
isAliveLock.RUnlock()
if !isAlive1 {
break
}
}
}()
ch := make(chan os.Signal, 1)
signal.Notify(ch, syscall.SIGTERM, syscall.SIGINT, syscall.SIGKILL)
// syscall.SIGKILL
// kill -9 pid
// kill -s SIGKILL pid 还是留给运维吧
//
// 自动退出条件:
//
var suideTime time.Time
for {
var sockets []zmq.Polled
var err error
sockets, err = poller2.Poll(HEARTBEAT_INTERVAL)
if err != nil {
// break // Interrupted
log.Errorf("Error When Pollling: %v\n", err)
continue
}
hasValidMsg := false
for _, socket := range sockets {
switch socket.Socket {
case backend:
// 格式:
// 后端:
// <"", proxy_id, "", client_id, "", rpc_data>
// Backend Socket读取到的:
// <wokerid, "", proxy_id, "", client_id, "", rpc_data>
//
msgs, err := backend.RecvMessage(0)
if err != nil {
log.Errorf("Error When RecvMessage from background: %v\n", err)
continue
}
if config.VERBOSE {
// log.Println("Message from backend: ", msgs)
}
// 消息类型:
// msgs: <worker_id, "", proxy_id, "", client_id, "", rpc_data>
// <worker_id, "", rpc_control_data>
worker_id, msgs := utils.Unwrap(msgs)
// rpc_control_data 控制信息
// msgs: <rpc_control_data>
if len(msgs) == 1 {
// PPP_READY
// PPP_HEARTBEAT
controlMsg := msgs[0]
// 碰到无效的信息，则直接跳过去
if len(controlMsg) == 0 {
continue
}
if config.VERBOSE {
// log.Println("Got Message From Backend...")
}
if controlMsg[0] == PPP_READY || controlMsg[0] == PPP_HEARTBEAT {
// 后端服务剩余的并发能力
var concurrency int
if len(controlMsg) >= 3 {
concurrency = int(controlMsg[2])
} else {
concurrency = 1
}
if config.VERBOSE {
// utils.PrintZeromqMsgs(msgs, "control msg")
}
force_update := controlMsg[0] == PPP_READY
workersQueue.UpdateWorkerStatus(worker_id, concurrency, force_update)
} else if controlMsg[0] == PPP_STOP {
// 停止指定的后端服务
workersQueue.UpdateWorkerStatus(worker_id, -1, true)
} else {
log.Errorf("Unexpected Control Message: %d", controlMsg[0])
}
} else {
hasValidMsg = true
// 将信息发送到前段服务, 如果前端服务挂了，则消息就丢失
// log.Println("Send Message to frontend")
workersQueue.UpdateWorkerStatus(worker_id, 0, false)
// msgs: <proxy_id, "", client_id, "", rpc_data>
frontend.SendMessage(msgs)
}
case frontend:
hasValidMsg = true
log.Println("----->Message from front: ")
msgs, err := frontend.RecvMessage(0)
if err != nil {
log.Errorf("Error when reading from frontend: %v\n", err)
continue
}
// msgs:
// <proxy_id, "", client_id, "", rpc_data>
if config.VERBOSE {
utils.PrintZeromqMsgs(msgs, "frontend")
}
msgs = utils.TrimLeftEmptyMsg(msgs)
// 将msgs交给后端服务器
worker := workersQueue.NextWorker()
if worker != nil {
if config.VERBOSE {
log.Println("Send Msg to Backend worker: ", worker.Identity)
}
backend.SendMessage(worker.Identity, "", msgs)
} else {
// 怎么返回错误消息呢?
if config.VERBOSE {
log.Println("No backend worker found")
}
errMsg := proxy.GetWorkerNotFoundData("account", 0)
// <proxy_id, "", client_id, "", rpc_data>
frontend.SendMessage(msgs[0:(len(msgs)-1)], errMsg)
}
}
}
// 如果安排的suiside, 则需要处理 suiside的时间
isAliveLock.RLock()
isAlive1 := isAlive
isAliveLock.RUnlock()
if !isAlive1 {
if hasValidMsg {
suideTime = time.Now().Add(time.Second * 3)
} else {
if time.Now().After(suideTime) {
log.Println(utils.Green("Load Balance Suiside Gracefully"))
break
}
}
}
// 心跳同步
select {
case <-heartbeat_at:
now := time.Now()
// 给workerQueue中的所有的worker发送心跳消息
for _, worker := range workersQueue.WorkerQueue {
if worker.Expire.After(now) {
// log.Println("Sending Hb to Worker: ", worker.Identity)
backend.SendMessage(worker.Identity, "", PPP_HEARTBEAT_STR)
}
}
workersQueue.PurgeExpired()
case sig := <-ch:
isAliveLock.Lock()
isAlive1 := isAlive
isAlive = false
isAliveLock.Unlock()
if isAlive1 {
// 准备退出(但是需要处理完毕手上的活)
// 需要退出:
topo.DeleteServiceEndPoint(serviceName, lbServiceName)
if sig == syscall.SIGKILL {
log.Println(utils.Red("Got Kill Signal, Return Directly"))
break
} else {
suideTime = time.Now().Add(time.Second * 3)
log.Println(utils.Red("Schedule to suicide at: "), suideTime.Format("@2006-01-02 15:04:05"))
}
}
default:
}
}
}
func (p *ThriftLoadBalanceServer) Run() {
// // 1. 创建到zk的连接
// 127.0.0.1:5555 --> 127_0_0_1:5555
exitSignal := make(chan os.Signal, 1)
signal.Notify(exitSignal, syscall.SIGTERM, syscall.SIGINT, syscall.SIGKILL)
// syscall.SIGKILL
// kill -9 pid
// kill -s SIGKILL pid 还是留给运维吧
//
// 注册服务
evtExit := make(chan interface{})
serviceEndpoint := RegisterService(p.serviceName, p.frontendAddr, p.lbServiceName,
p.topo, evtExit, p.config.WorkDir, p.config.CodeUrlVersion)
// var suideTime time.Time
// isAlive := true
// 3. 读取后端服务的配置
var transport thrift.TServerTransport
var err error
isUnixDomain := false
// 127.0.0.1:9999(以:区分不同的类型)
if !strings.Contains(p.frontendAddr, ":") {
if FileExist(p.frontendAddr) {
os.Remove(p.frontendAddr)
}
transport, err = NewTServerUnixDomain(p.frontendAddr)
isUnixDomain = true
} else {
transport, err = thrift.NewTServerSocket(p.frontendAddr)
}
if err != nil {
log.ErrorErrorf(err, "Server Socket Create Failed: %v", err)
panic(fmt.Sprintf("Invalid FrontendAddress: %s", p.frontendAddr))
}
err = transport.Listen()
if err != nil {
log.ErrorErrorf(err, "Server Socket Create Failed: %v", err)
panic(fmt.Sprintf("Binding Error FrontendAddress: %s", p.frontendAddr))
}
ch := make(chan thrift.TTransport, 4096)
defer close(ch)
// 强制退出? TODO: Graceful退出
go func() {
<-exitSignal
// 通知RegisterService终止循环
evtExit <- true
log.Info(Green("Receive Exit Signals...."))
serviceEndpoint.DeleteServiceEndpoint(p.topo)
start := time.Now().Unix()
for true {
// 如果5s内没有接受到新的请求了，则退出
now := time.Now().Unix()
if now-p.lastRequestTime.Get() > 5 {
log.Printf(Red("[%s]Graceful Exit..."), p.serviceName)
break
} else {
log.Printf(Cyan("[%s]Sleeping %d seconds before Exit...\n"),
p.serviceName, now-start)
time.Sleep(time.Second)
}
}
transport.Interrupt()
transport.Close()
}()
go func() {
var address string
for c := range ch {
// 为每个Connection建立一个Session
socket, ok := c.(SocketAddr)
if ok {
if isUnixDomain {
address = p.frontendAddr
} else {
address = socket.Addr().String()
}
} else {
address = "unknow"
}
x := NewNonBlockSession(c, address, p.verbose, &p.lastRequestTime)
// Session独立处理自己的请求
go x.Serve(p.backendService, 1000)
}
}()
// Accept什么时候出错，出错之后如何处理呢?
for {
c, err := transport.Accept()
if err != nil {
close(ch)
break
} else {
ch <- c
}
}
}
//
// go test github.com/wfxiang08/rpc_proxy/proxy -v -run "TestSession"
//
func TestSession(t *testing.T) {
// 作为一个Server
transport, err := thrift.NewTServerSocket("127.0.0.1:0")
assert.NoError(t, err)
err = transport.Open() // 打开Transport
assert.NoError(t, err)
defer transport.Close()
err = transport.Listen() // 开始监听
assert.NoError(t, err)
addr := transport.Addr().String()
fmt.Println("Addr: ", addr)
var requestNum int32 = 10
requests := make([]*Request, 0, requestNum)
var i int32
for i = 0; i < requestNum; i++ {
buf := make([]byte, 100, 100)
l := fakeData("Hello", thrift.CALL, i+1, buf[0:0])
buf = buf[0:l]
req := NewRequest(buf, true)
req.Wait.Add(1) // 因为go routine可能还没有执行，代码就跑到最后面进行校验了
assert.Equal(t, i+1, req.Request.SeqId, "Request SeqId是否靠谱")
requests = append(requests, req)
}
go func() {
// 模拟请求:
// 客户端代码
bc := NewBackendConn(addr, nil, "test", true)
bc.currentSeqId = 10
// 准备发送数据
var i int32
for i = 0; i < requestNum; i++ {
fmt.Println("Sending Request to Backend Conn", i)
bc.PushBack(requests[i])
requests[i].Wait.Done()
}
// 需要等待数据返回?
time.Sleep(time.Second * 2)
}()
server := &fakeServer{}
go func() {
// 服务器端代码
tran, err := transport.Accept()
defer tran.Close()
if err != nil {
log.ErrorErrorf(err, "Error: %v\n", err)
}
assert.NoError(t, err)
session := NewSession(tran, "", true)
session.Serve(server, 6)
time.Sleep(time.Second * 2)
}()
for i = 0; i < requestNum; i++ {
fmt.Println("===== Before Wait")
requests[i].Wait.Wait()
fmt.Println("===== Before After Wait")
log.Printf("Request: %d, .....", i)
assert.Equal(t, len(requests[i].Response.Data), len(requests[i].Request.Data))
}
}
//
// 如何处理后端服务的变化呢?
//
func (s *BackService) WatchBackServiceNodes() {
s.evtbus = make(chan interface{}, 2)
servicePath := s.topo.ProductServicePath(s.serviceName)
go func() {
for !s.stop.Get() {
serviceIds, err := s.topo.WatchChildren(servicePath, s.evtbus)
if err == nil {
// 如何监听endpoints的变化呢?
addressMap := make(map[string]bool, len(serviceIds))
for _, serviceId := range serviceIds {
log.Printf(Green("---->Find Endpoint: %s for Service: %s"), serviceId, s.serviceName)
endpointInfo, err := GetServiceEndpoint(s.topo, s.serviceName, serviceId)
if err != nil {
log.ErrorErrorf(err, "Service Endpoint Read Error: %v\n", err)
} else {
log.Printf(Green("---->Add endpoint %s To Service %s"),
endpointInfo.Frontend, s.serviceName)
if strings.Contains(endpointInfo.Frontend, ":") {
addressMap[endpointInfo.Frontend] = true
} else if s.productName == TEST_PRODUCT_NAME {
// unix domain socket只在测试的时候可以使用(因为不能实现跨机器访问）
addressMap[endpointInfo.Frontend] = true
}
}
}
for addr, _ := range addressMap {
conn, ok := s.addr2Conn[addr]
if ok && !conn.IsMarkOffline.Get() {
continue
} else {
// 创建新的连接（心跳成功之后就自动加入到 s.activeConns 中
s.addr2Conn[addr] = NewBackendConn(addr, s, s.serviceName, s.verbose)
}
}
for addr, conn := range s.addr2Conn {
_, ok := addressMap[addr]
if !ok {
conn.MarkOffline()
// 删除: 然后等待Conn自生自灭
delete(s.addr2Conn, addr)
}
}
// 等待事件
<-s.evtbus
} else {
log.WarnErrorf(err, "zk read failed: %s", servicePath)
// 如果读取失败则，则继续等待5s
time.Sleep(time.Duration(5) * time.Second)
}
}
}()
}
//
// go test github.com/wfxiang08/rpc_proxy/proxy -v -run "TestBackend"
//
func TestBackend(t *testing.T) {
// 作为一个Server
transport, err := thrift.NewTServerSocket("127.0.0.1:0")
assert.NoError(t, err)
err = transport.Open() // 打开Transport
assert.NoError(t, err)
defer transport.Close()
err = transport.Listen() // 开始监听
assert.NoError(t, err)
addr := transport.Addr().String()
fmt.Println("Addr: ", addr)
var requestNum int32 = 10
requests := make([]*Request, 0, requestNum)
var i int32
for i = 0; i < requestNum; i++ {
buf := make([]byte, 100, 100)
l := fakeData("Hello", thrift.CALL, i+1, buf[0:0])
buf = buf[0:l]
req := NewRequest(buf, false)
req.Wait.Add(1) // 因为go routine可能还没有执行，代码就跑到最后面进行校验了
assert.Equal(t, i+1, req.Request.SeqId, "Request SeqId是否靠谱")
requests = append(requests, req)
}
go func() {
// 客户端代码
bc := NewBackendConn(addr, nil, "test", true)
bc.currentSeqId = 10
// 准备发送数据
var i int32
for i = 0; i < requestNum; i++ {
fmt.Println("Sending Request to Backend Conn", i)
bc.PushBack(requests[i])
requests[i].Wait.Done()
}
// 需要等待数据返回?
time.Sleep(time.Second * 2)
}()
go func() {
// 服务器端代码
tran, err := transport.Accept()
if err != nil {
log.ErrorErrorf(err, "Error: %v\n", err)
}
assert.NoError(t, err)
bt := NewTBufferedFramedTransport(tran, time.Microsecond*100, 2)
// 在当前的这个t上读写数据
var i int32
for i = 0; i < requestNum; i++ {
request, err := bt.ReadFrame()
assert.NoError(t, err)
req := NewRequest(request, false)
assert.Equal(t, req.Request.SeqId, i+10)
fmt.Printf("Server Got Request, and SeqNum OK, Id: %d, Frame Size: %d\n", i, len(request))
// 回写数据
bt.Write(request)
bt.FlushBuffer(true)
}
tran.Close()
}()
fmt.Println("Requests Len: ", len(requests))
for idx, r := range requests {
r.Wait.Wait()
// r 原始的请求
req := NewRequest(r.Response.Data, false)
log.Printf(Green("SeqMatch[%d]: Orig: %d, Return: %d\n"), idx, req.Request.SeqId, r.Request.SeqId)
assert.Equal(t, req.Request.SeqId, r.Request.SeqId)
}
log.Println("OK")
}
func RpcMain(binaryName string, serviceDesc string, configCheck ConfigCheck,
serverFactory ServerFactorory, buildDate string, gitVersion string) {
// 1. 准备解析参数
usage = fmt.Sprintf(usage, binaryName, binaryName)
version := fmt.Sprintf("Version: %s\nBuildDate: %s\nDesc: %s\nAuthor: [email protected]", gitVersion, buildDate, serviceDesc)
args, err := docopt.Parse(usage, nil, true, version, true)
if err != nil {
fmt.Println(err)
os.Exit(1)
}
if s, ok := args["-V"].(bool); ok && s {
fmt.Println(Green(version))
os.Exit(1)
}
// 这就是为什么 Codis 傻乎乎起一个 http server的目的
if s, ok := args["--profile-addr"].(string); ok && len(s) > 0 {
go func() {
log.Printf(Red("Profile Address: %s"), s)
log.Println(http.ListenAndServe(s, nil))
}()
}
// 2. 解析Log相关的配置
log.SetLevel(log.LEVEL_INFO)
var maxKeepDays int = 3
if s, ok := args["--log-keep-days"].(string); ok && s != "" {
v, err := strconv.ParseInt(s, 10, 32)
if err != nil {
log.PanicErrorf(err, "invalid max log file keep days = %s", s)
}
maxKeepDays = int(v)
}
// set output log file
if s, ok := args["-L"].(string); ok && s != "" {
f, err := log.NewRollingFile(s, maxKeepDays)
if err != nil {
log.PanicErrorf(err, "open rolling log file failed: %s", s)
} else {
defer f.Close()
log.StdLog = log.New(f, "")
}
}
log.SetLevel(log.LEVEL_INFO)
log.SetFlags(log.Flags() | log.Lshortfile)
// set log level
if s, ok := args["--log-level"].(string); ok && s != "" {
SetLogLevel(s)
}
// 没有就没有
workDir, _ := args["--work-dir"].(string)
codeUrlVersion, _ := args["--code-url-version"].(string)
if len(workDir) == 0 {
workDir, _ = os.Getwd()
}
log.Printf("WorkDir: %s, CodeUrl: %s, Wd: %s", workDir, codeUrlVersion)
// 3. 解析Config
configFile := args["-c"].(string)
conf, err := utils.LoadConf(configFile)
if err != nil {
log.PanicErrorf(err, "load config failed")
}
// 额外的配置信息
conf.WorkDir = workDir
conf.CodeUrlVersion = codeUrlVersion
if configCheck != nil {
configCheck(conf)
} else {
log.Panic("No Config Check Given")
}
// 每次启动的时候都打印版本信息
log.Infof(Green("-----------------\n%s\n--------------------------------------------------------------------"), version)
// 启动服务
server := serverFactory(conf)
server.Run()
}
func (s *BackServiceLB) run() {
go func() {
// 定时汇报当前的状态
for true {
log.Printf(Green("[Report]: %s --> %d workers, coroutine: %d"),
s.serviceName, s.Active(), runtime.NumGoroutine())
time.Sleep(time.Second * 10)
}
}()
var transport thrift.TServerTransport
var err error
// 3. 读取后端服务的配置
isUnixDomain := false
// 127.0.0.1:9999(以:区分不同的类型)
if !strings.Contains(s.backendAddr, ":") {
if FileExist(s.backendAddr) {
os.Remove(s.backendAddr)
}
transport, err = NewTServerUnixDomain(s.backendAddr)
isUnixDomain = true
} else {
transport, err = thrift.NewTServerSocket(s.backendAddr)
}
if err != nil {
log.ErrorErrorf(err, "[%s]Server Socket Create Failed: %v", s.serviceName, err)
panic("BackendAddr Invalid")
}
err = transport.Listen()
if err != nil {
log.ErrorErrorf(err, "[%s]Server Socket Open Failed: %v", s.serviceName, err)
panic("Server Socket Open Failed")
}
// 和transport.open做的事情一样，如果Open没错，则Listen也不会有问题
log.Printf(Green("[%s]LB Backend Services listens at: %s"), s.serviceName, s.backendAddr)
s.ch = make(chan thrift.TTransport, 4096)
// 强制退出? TODO: Graceful退出
go func() {
<-s.exitEvt
log.Info(Red("Receive Exit Signals...."))
transport.Interrupt()
transport.Close()
}()
go func() {
var backendAddr string
for trans := range s.ch {
// 为每个Connection建立一个Session
socket, ok := trans.(SocketAddr)
if ok {
if isUnixDomain {
backendAddr = s.backendAddr
} else {
backendAddr = socket.Addr().String()
}
conn := NewBackendConnLB(trans, s.serviceName, backendAddr, s, s.verbose)
// 因为连接刚刚建立，可靠性还是挺高的，因此直接加入到列表中
s.activeConnsLock.Lock()
conn.Index = len(s.activeConns)
s.activeConns = append(s.activeConns, conn)
s.activeConnsLock.Unlock()
log.Printf(Green("%s --> %d workers"), s.serviceName, conn.Index)
} else {
panic("Invalid Socket Type")
}
}
}()
// Accept什么时候出错，出错之后如何处理呢?
go func() {
for {
c, err := transport.Accept()
if err != nil {
return
} else {
s.ch <- c
}
}
}()
}
func (s *Session) Close() error {
s.closed.Set(true)
log.Printf(Red("Close Proxy Session"))
return s.TBufferedFramedTransport.Close()
}