Code optimization

vender/github.com/astaxie/beego/grace/grace.go

@@ -0,0 +1,166 @@
+// Copyright 2014 beego Author. All Rights Reserved.
+//
+// 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 grace use to hot reload
+// Description: http://grisha.org/blog/2014/06/03/graceful-restart-in-golang/
+//
+// Usage:
+//
+// import(
+//   "log"
+//	 "net/http"
+//	 "os"
+//
+//   "github.com/cnlh/nps/vender/github.com/astaxie/beego/grace"
+// )
+//
+//  func handler(w http.ResponseWriter, r *http.Request) {
+//	  w.Write([]byte("WORLD!"))
+//  }
+//
+//  func main() {
+//      mux := http.NewServeMux()
+//      mux.HandleFunc("/hello", handler)
+//
+//	    err := grace.ListenAndServe("localhost:8080", mux)
+//      if err != nil {
+//		   log.Println(err)
+//	    }
+//      log.Println("Server on 8080 stopped")
+//	     os.Exit(0)
+//    }
+package grace
+
+import (
+	"flag"
+	"net/http"
+	"os"
+	"strings"
+	"sync"
+	"syscall"
+	"time"
+)
+
+const (
+	// PreSignal is the position to add filter before signal
+	PreSignal = iota
+	// PostSignal is the position to add filter after signal
+	PostSignal
+	// StateInit represent the application inited
+	StateInit
+	// StateRunning represent the application is running
+	StateRunning
+	// StateShuttingDown represent the application is shutting down
+	StateShuttingDown
+	// StateTerminate represent the application is killed
+	StateTerminate
+)
+
+var (
+	regLock              *sync.Mutex
+	runningServers       map[string]*Server
+	runningServersOrder  []string
+	socketPtrOffsetMap   map[string]uint
+	runningServersForked bool
+
+	// DefaultReadTimeOut is the HTTP read timeout
+	DefaultReadTimeOut time.Duration
+	// DefaultWriteTimeOut is the HTTP Write timeout
+	DefaultWriteTimeOut time.Duration
+	// DefaultMaxHeaderBytes is the Max HTTP Herder size, default is 0, no limit
+	DefaultMaxHeaderBytes int
+	// DefaultTimeout is the shutdown server's timeout. default is 60s
+	DefaultTimeout = 60 * time.Second
+
+	isChild     bool
+	socketOrder string
+
+	hookableSignals []os.Signal
+)
+
+func init() {
+	flag.BoolVar(&isChild, "graceful", false, "listen on open fd (after forking)")
+	flag.StringVar(&socketOrder, "socketorder", "", "previous initialization order - used when more than one listener was started")
+
+	regLock = &sync.Mutex{}
+	runningServers = make(map[string]*Server)
+	runningServersOrder = []string{}
+	socketPtrOffsetMap = make(map[string]uint)
+
+	hookableSignals = []os.Signal{
+		syscall.SIGHUP,
+		syscall.SIGINT,
+		syscall.SIGTERM,
+	}
+}
+
+// NewServer returns a new graceServer.
+func NewServer(addr string, handler http.Handler) (srv *Server) {
+	regLock.Lock()
+	defer regLock.Unlock()
+
+	if !flag.Parsed() {
+		flag.Parse()
+	}
+	if len(socketOrder) > 0 {
+		for i, addr := range strings.Split(socketOrder, ",") {
+			socketPtrOffsetMap[addr] = uint(i)
+		}
+	} else {
+		socketPtrOffsetMap[addr] = uint(len(runningServersOrder))
+	}
+
+	srv = &Server{
+		wg:      sync.WaitGroup{},
+		sigChan: make(chan os.Signal),
+		isChild: isChild,
+		SignalHooks: map[int]map[os.Signal][]func(){
+			PreSignal: {
+				syscall.SIGHUP:  {},
+				syscall.SIGINT:  {},
+				syscall.SIGTERM: {},
+			},
+			PostSignal: {
+				syscall.SIGHUP:  {},
+				syscall.SIGINT:  {},
+				syscall.SIGTERM: {},
+			},
+		},
+		state:   StateInit,
+		Network: "tcp",
+	}
+	srv.Server = &http.Server{}
+	srv.Server.Addr = addr
+	srv.Server.ReadTimeout = DefaultReadTimeOut
+	srv.Server.WriteTimeout = DefaultWriteTimeOut
+	srv.Server.MaxHeaderBytes = DefaultMaxHeaderBytes
+	srv.Server.Handler = handler
+
+	runningServersOrder = append(runningServersOrder, addr)
+	runningServers[addr] = srv
+
+	return
+}
+
+// ListenAndServe refer http.ListenAndServe
+func ListenAndServe(addr string, handler http.Handler) error {
+	server := NewServer(addr, handler)
+	return server.ListenAndServe()
+}
+
+// ListenAndServeTLS refer http.ListenAndServeTLS
+func ListenAndServeTLS(addr string, certFile string, keyFile string, handler http.Handler) error {
+	server := NewServer(addr, handler)
+	return server.ListenAndServeTLS(certFile, keyFile)
+}