package nsqlookupd
import (
"fmt"
"net"
"os"
"sync"
"github.com/nsqio/nsq/internal/http_api"
"github.com/nsqio/nsq/internal/protocol"
"github.com/nsqio/nsq/internal/util"
"github.com/nsqio/nsq/internal/version"
)type NSQLookupd struct {
sync.RWMutex
opts *Options
tcpListener net.Listener
httpListener net.Listener
waitGroup util.WaitGroupWrapper
DB *RegistrationDB
}func New(opts *Options) *NSQLookupd {
n := &NSQLookupd{
opts: opts,
DB: NewRegistrationDB(),
}
n.logf(version.String("nsqlookupd"))
return n
}func (l *NSQLookupd) logf(f string, args ...interface{}) {
if l.opts.Logger == nil {
return
}
l.opts.Logger.Output(2, fmt.Sprintf(f, args...))
}func (l *NSQLookupd) Main() {
ctx := &Context{l}
tcpListener, err := net.Listen("tcp", l.opts.TCPAddress)
if err != nil {
l.logf("FATAL: listen (%s) failed - %s", l.opts.TCPAddress, err)
os.Exit(1)
}
l.Lock()
l.tcpListener = tcpListener
l.Unlock()
tcpServer := &tcpServer{ctx: ctx}
l.waitGroup.Wrap(func() {
protocol.TCPServer(tcpListener, tcpServer, l.opts.Logger)
})
httpListener, err := net.Listen("tcp", l.opts.HTTPAddress)
if err != nil {
l.logf("FATAL: listen (%s) failed - %s", l.opts.HTTPAddress, err)
os.Exit(1)
}
l.Lock()
l.httpListener = httpListener
l.Unlock()
httpServer := newHTTPServer(ctx)
l.waitGroup.Wrap(func() {
http_api.Serve(httpListener, httpServer, "HTTP", l.opts.Logger)
})
}func (l *NSQLookupd) RealTCPAddr() *net.TCPAddr {
l.RLock()
defer l.RUnlock()
return l.tcpListener.Addr().(*net.TCPAddr)
}func (l *NSQLookupd) RealHTTPAddr() *net.TCPAddr {
l.RLock()
defer l.RUnlock()
return l.httpListener.Addr().(*net.TCPAddr)
}func (l *NSQLookupd) Exit() {
if l.tcpListener != nil {
l.tcpListener.Close()
}
if l.httpListener != nil {
l.httpListener.Close()
}
l.waitGroup.Wait()
}原文：http://www.cnblogs.com/zhangboyu/p/7457146.html