/
client.go
201 lines (184 loc) · 4.55 KB
/
client.go
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package bercon
import (
"fmt"
"io"
"net"
"sync/atomic"
"time"
"github.com/golang/glog"
)
//New creates a Client with given Config
func New(bec BeCfg) *Client {
cfg := bec.GetConfig()
if cfg.KeepAliveTimer == 0 {
cfg.KeepAliveTimer = 10 //TODO: Evaluate default value
}
return &Client{
addr: cfg.Addr,
password: cfg.Password,
keepAliveTimer: cfg.KeepAliveTimer,
keepAliveTolerance: cfg.KeepAliveTolerance,
readBuffer: make([]byte, 4096),
reconnectTimeout: 25,
cmdChan: make(chan transmission),
cmdMap: make(map[byte]transmission),
}
}
//Connect opens a new Connection to the Server
func (c *Client) Connect() (err error) {
c.con, err = net.DialUDP("udp", nil, c.addr)
if err != nil {
c.con = nil
return err
}
//Read Buffer
buffer := make([]byte, 9)
glog.V(2).Infoln("Sending Login Information")
c.con.SetReadDeadline(time.Now().Add(time.Second * 2))
c.con.Write(buildLoginPacket(c.password))
n, err := c.con.Read(buffer)
if err, ok := err.(net.Error); ok && err.Timeout() {
c.con.Close()
return ErrTimeout
}
if err != nil {
c.con.Close()
return err
}
response, err := verifyLogin(buffer[:n])
if err != nil {
c.con.Close()
return err
}
if response == packetResponse.LoginFail {
glog.Errorln("Non Login Packet Received:", response)
c.con.Close()
return ErrInvalidLogin
}
fmt.Println("Login successful")
if !c.looping {
c.looping = true
c.init = true
c.sequence.s = 0
c.keepAliveCount = 0
c.pingbackCount = 0
c.cmdLock.Lock()
c.cmdMap = make(map[byte]transmission)
c.cmdLock.Unlock()
go c.WatcherLoop()
}
return nil
}
//WatcherLoop is responsible for creating and keeping working connections
func (c *Client) WatcherLoop() {
writerDisconnect := make(chan int)
readerDisconnect := make(chan int)
// Start Loops only if initial connection is up
if c.init {
go c.writerLoop(writerDisconnect, c.cmdChan)
go c.readerLoop(readerDisconnect)
}
for {
glog.V(10).Infoln("Looping in WatcherLoop")
if !c.looping {
if err := c.Reconnect(); err != nil {
glog.V(2).Info(err)
time.Sleep(time.Second * 3)
continue
}
return
}
select {
case d := <-readerDisconnect:
c.looping = false
glog.V(2).Infoln("Reader disconnected, waiting for Writer")
_ = <-writerDisconnect
glog.V(2).Infoln("Writer disconnected")
glog.Warningf("Trying to recover from broken Connection (close msg: %v)", d)
if err := c.Reconnect(); err == nil {
return
}
case d := <-writerDisconnect:
c.looping = false
glog.V(2).Infoln("Writer disconnected, waiting for Reader")
_ = <-readerDisconnect
glog.V(2).Infoln("Reader disconnected")
glog.Warningf("Trying to recover from broken Connection (close msg: %v)", d)
if err := c.Reconnect(); err == nil {
return
}
//TODO: Evaluate it this is required
//default:
// continue
}
}
}
//Reconnect after loops exited or if not running
func (c *Client) Reconnect() error {
//c.con.Close()
var err error
if err = c.Connect(); err == nil {
return nil
}
if err != nil {
return err
}
return nil
}
//Disconnect the Client
func (c *Client) Disconnect() error {
return nil
}
//SetChatWriter enables Chat Reading and sets Writer
func (c *Client) SetChatWriter(w io.Writer) {
c.chatWriter.Lock()
c.chatWriter.Writer = w
c.chatWriter.Unlock()
}
//SetEventWriter enables Event Reading and sets Writer
func (c *Client) SetEventWriter(w io.Writer) {
c.eventWriter.Lock()
c.eventWriter.Writer = w
c.eventWriter.Unlock()
}
//RunCommand adds given cmd to command queue
func (c *Client) RunCommand(cmd string, w io.WriteCloser) {
c.cmdChan <- transmission{command: []byte(cmd), writeCloser: w}
}
func (c *Client) handleResponse(seq byte, response []byte, last bool) {
c.cmdLock.RLock()
trm, ex := c.cmdMap[seq]
c.cmdLock.RUnlock()
if !ex {
if len(response) == 0 {
c.sequence.Lock()
se := c.sequence.s
c.sequence.Unlock()
if se == seq {
glog.V(3).Infoln("Received KeepAlive Pingback")
atomic.AddInt64(&c.pingbackCount, 1)
}
} else {
glog.Warningf("No Entry in cmdMap for: %v - (%v)", string(response), response)
}
} else {
trail := []byte("\n")
if !last {
trail = []byte{}
}
trm.response = append(trm.response, response...)
trm.response = append(trm.response, trail...)
if last {
if trm.writeCloser != nil {
trm.writeCloser.Write(trm.response)
trm.writeCloser.Close()
}
//TODO: Evaluate if this is required
go func(c *Client, seq byte) {
c.cmdLock.Lock()
delete(c.cmdMap, seq)
c.cmdLock.Unlock()
}(c, seq)
}
}
}