Documentation
¶
Overview ¶
Example (HttpShutdown) ¶
This shows how to use the upgrader with the graceful shutdown facilities of net/http.
package main
import (
"context"
"flag"
"fmt"
upgrader "github.com/iamxvbaba/server/upgrader"
"log"
"net/http"
"os"
"os/signal"
"syscall"
"time"
)
func main() {
var (
listenAddr = flag.String("listen", "localhost:8080", "`Address` to listen on")
pidFile = flag.String("pid-file", "", "`Path` to pid file")
)
flag.Parse()
log.SetPrefix(fmt.Sprintf("%d ", os.Getpid()))
upg, err := upgrader.New(upgrader.Options{
PIDFile: *pidFile,
})
if err != nil {
panic(err)
}
defer upg.Stop()
// Do an upgrade on SIGHUP
go func() {
sig := make(chan os.Signal, 1)
signal.Notify(sig, syscall.SIGHUP)
for range sig {
err := upg.Upgrade()
if err != nil {
log.Println("Upgrade failed:", err)
}
}
}()
// Listen must be called before Ready
ln, err := upg.Listen("tcp", *listenAddr)
if err != nil {
log.Fatalln("Can't listen:", err)
}
server := http.Server{
// Set timeouts, etc.
}
go func() {
err := server.Serve(ln)
if err != http.ErrServerClosed {
log.Println("HTTP server:", err)
}
}()
log.Printf("ready")
if err := upg.Ready(); err != nil {
panic(err)
}
<-upg.Exit()
// Make sure to set a deadline on exiting the process
// after upg.Exit() is closed. No new upgrades can be
// performed if the parent doesn't exit.
time.AfterFunc(30*time.Second, func() {
log.Println("Graceful shutdown timed out")
os.Exit(1)
})
// Wait for connections to drain.
server.Shutdown(context.Background())
}
Output:
Example (TcpServer) ¶
This shows how to use the Upgrader with a listener based service.
package main
import (
"flag"
"fmt"
upgrader "github.com/iamxvbaba/server/upgrader"
"log"
"os"
"os/signal"
"syscall"
"time"
)
func main() {
var (
listenAddr = flag.String("listen", "localhost:8080", "`Address` to listen on")
pidFile = flag.String("pid-file", "", "`Path` to pid file")
)
flag.Parse()
log.SetPrefix(fmt.Sprintf("%d ", os.Getpid()))
upg, err := upgrader.New(upgrader.Options{
PIDFile: *pidFile,
})
if err != nil {
panic(err)
}
defer upg.Stop()
// Do an upgrade on SIGHUP
go func() {
sig := make(chan os.Signal, 1)
signal.Notify(sig, syscall.SIGHUP)
for range sig {
err := upg.Upgrade()
if err != nil {
log.Println("upgrade failed:", err)
}
}
}()
ln, err := upg.Fds.Listen("tcp", *listenAddr)
if err != nil {
log.Fatalln("Can't listen:", err)
}
go func() {
defer ln.Close()
log.Printf("listening on %s", ln.Addr())
for {
c, err := ln.Accept()
if err != nil {
return
}
go func() {
c.SetDeadline(time.Now().Add(time.Second))
c.Write([]byte("It is a mistake to think you can solve any major problems just with potatoes.\n"))
c.Close()
}()
}
}()
log.Printf("ready")
if err := upg.Ready(); err != nil {
panic(err)
}
<-upg.Exit()
}
Output:
Index ¶
- Constants
- Variables
- type Conn
- type Fds
- func (f *Fds) AddConn(network, addr string, conn Conn) error
- func (f *Fds) AddFile(name string, file *os.File) error
- func (f *Fds) AddListener(network, addr string, ln Listener) error
- func (f *Fds) AddPacketConn(network, addr string, conn PacketConn) error
- func (f *Fds) Conn(network, addr string) (net.Conn, error)
- func (f *Fds) File(name string) (*os.File, error)
- func (f *Fds) Listen(network, addr string) (net.Listener, error)
- func (f *Fds) ListenPacket(network, addr string) (net.PacketConn, error)
- func (f *Fds) ListenPacketWithCallback(network, addr string, ...) (net.PacketConn, error)
- func (f *Fds) ListenWithCallback(network, addr string, ...) (net.Listener, error)
- func (f *Fds) Listener(network, addr string) (net.Listener, error)
- func (f *Fds) PacketConn(network, addr string) (net.PacketConn, error)
- type Listener
- type Options
- type PacketConn
- type Upgrader
Examples ¶
Constants ¶
const DefaultUpgradeTimeout time.Duration = time.Minute
DefaultUpgradeTimeout is the duration before the Upgrader kills the new process if no readiness notification was received.
Variables ¶
var ErrNotSupported = errors.New("upgrader: platform does not support graceful restart")
Functions ¶
This section is empty.
Types ¶
type Fds ¶
type Fds struct {
// contains filtered or unexported fields
}
Fds 保留从父进程继承的所有文件描述符。
func (*Fds) AddConn ¶
AddConn adds a connection.
It is safe to close conn after calling this method.
func (*Fds) AddListener ¶
AddListener adds a listener.
It is safe to close ln after calling the method. Any existing listener with the same address is overwitten.
func (*Fds) AddPacketConn ¶
func (f *Fds) AddPacketConn(network, addr string, conn PacketConn) error
AddPacketConn adds a PacketConn.
It is safe to close conn after calling the method. Any existing packet connection with the same address is overwitten.
func (*Fds) Conn ¶
Conn returns an inherited connection or nil.
It is safe to close the returned Conn.
func (*Fds) ListenPacket ¶
func (f *Fds) ListenPacket(network, addr string) (net.PacketConn, error)
ListenPacket returns a packet conn inherited from the parent process, or creates a new one.
func (*Fds) ListenPacketWithCallback ¶
func (f *Fds) ListenPacketWithCallback(network, addr string, callback func(network, addr string) (net.PacketConn, error)) (net.PacketConn, error)
ListenPacketWithCallback returns a packet conn inherited from the parent process, or calls the supplied callback to create a new one.
This should be used in case some customization has to be applied to create the connection. Note that the callback must not use the underlying `Fds` object as it will be locked during the call.
func (*Fds) ListenWithCallback ¶
func (f *Fds) ListenWithCallback(network, addr string, callback func(network, addr string) (net.Listener, error)) (net.Listener, error)
ListenWithCallback 返回从父进程继承的侦听器，或调用提供的回调来创建一个新的侦听器。 如果必须应用某些自定义来创建连接，则应使用此方法。请注意，callback时不得使用基础的 Fds 对象，因为它将在调用过程中被锁定。
func (*Fds) Listener ¶
Listener returns an inherited listener or nil.
It is safe to close the returned listener.
func (*Fds) PacketConn ¶
func (f *Fds) PacketConn(network, addr string) (net.PacketConn, error)
PacketConn returns an inherited packet connection or nil.
It is safe to close the returned packet connection.
type Options ¶
type Options struct {
// Time after which an upgrade is considered failed. Defaults to
// DefaultUpgradeTimeout.
UpgradeTimeout time.Duration
// The PID of a ready process is written to this file.
PIDFile string
// ListenConfig is a custom ListenConfig. Defaults to an empty ListenConfig
ListenConfig *net.ListenConfig
}
Options control the behaviour of the Upgrader.
type PacketConn ¶
type PacketConn interface {
net.PacketConn
syscall.Conn
}
PacketConn can be shared between processes.
type Upgrader ¶
type Upgrader struct {
*Fds
// contains filtered or unexported fields
}
Upgrader handles zero downtime upgrades and passing files between processes.
func (*Upgrader) Exit ¶
func (u *Upgrader) Exit() <-chan struct{}
Exit returns a channel which is closed when the process should exit.
func (*Upgrader) HasParent ¶
HasParent checks if the current process is an upgrade or the first invocation.
func (*Upgrader) Stop ¶
func (u *Upgrader) Stop()
Stop prevents any more upgrades from happening, and closes the exit channel.
If this function is called before a call to Upgrade() has succeeded, it is assumed that the process is being shut down completely. All Unix sockets known to Upgrader.Fds are then unlinked from the filesystem.
Source Files
Directories