forkjo/modules/graceful/manager_unix.go
zeripath cbaa1de9ec Add Graceful shutdown for Windows and hooks for shutdown of goroutines (#8964)
* Graceful Shutdown for windows and others

Restructures modules/graceful, adding shutdown for windows, removing and
replacing the old minwinsvc code.

Creates a new waitGroup - terminate which allows for goroutines to
finish up after the shutdown of the servers.

Shutdown and terminate hooks are added for goroutines.

* Remove unused functions - these can be added in a different PR

* Add startup timeout functionality

* Document STARTUP_TIMEOUT
2019-11-21 13:32:02 -05:00

141 lines
3.3 KiB
Go

// +build !windows
// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package graceful
import (
"errors"
"os"
"os/signal"
"sync"
"syscall"
"time"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/setting"
)
type gracefulManager struct {
isChild bool
forked bool
lock *sync.RWMutex
state state
shutdown chan struct{}
hammer chan struct{}
terminate chan struct{}
runningServerWaitGroup sync.WaitGroup
createServerWaitGroup sync.WaitGroup
terminateWaitGroup sync.WaitGroup
}
func newGracefulManager() *gracefulManager {
manager := &gracefulManager{
isChild: len(os.Getenv(listenFDs)) > 0 && os.Getppid() > 1,
lock: &sync.RWMutex{},
}
manager.createServerWaitGroup.Add(numberOfServersToCreate)
manager.Run()
return manager
}
func (g *gracefulManager) Run() {
g.setState(stateRunning)
go g.handleSignals()
c := make(chan struct{})
go func() {
defer close(c)
// Wait till we're done getting all of the listeners and then close
// the unused ones
g.createServerWaitGroup.Wait()
// Ignore the error here there's not much we can do with it
// They're logged in the CloseProvidedListeners function
_ = CloseProvidedListeners()
}()
if setting.StartupTimeout > 0 {
go func() {
select {
case <-c:
return
case <-g.IsShutdown():
return
case <-time.After(setting.StartupTimeout):
log.Error("Startup took too long! Shutting down")
g.doShutdown()
}
}()
}
}
func (g *gracefulManager) handleSignals() {
var sig os.Signal
signalChannel := make(chan os.Signal, 1)
signal.Notify(
signalChannel,
syscall.SIGHUP,
syscall.SIGUSR1,
syscall.SIGUSR2,
syscall.SIGINT,
syscall.SIGTERM,
syscall.SIGTSTP,
)
pid := syscall.Getpid()
for {
sig = <-signalChannel
switch sig {
case syscall.SIGHUP:
if setting.GracefulRestartable {
log.Info("PID: %d. Received SIGHUP. Forking...", pid)
err := g.doFork()
if err != nil && err.Error() != "another process already forked. Ignoring this one" {
log.Error("Error whilst forking from PID: %d : %v", pid, err)
}
} else {
log.Info("PID: %d. Received SIGHUP. Not set restartable. Shutting down...", pid)
g.doShutdown()
}
case syscall.SIGUSR1:
log.Info("PID %d. Received SIGUSR1.", pid)
case syscall.SIGUSR2:
log.Warn("PID %d. Received SIGUSR2. Hammering...", pid)
g.doHammerTime(0 * time.Second)
case syscall.SIGINT:
log.Warn("PID %d. Received SIGINT. Shutting down...", pid)
g.doShutdown()
case syscall.SIGTERM:
log.Warn("PID %d. Received SIGTERM. Shutting down...", pid)
g.doShutdown()
case syscall.SIGTSTP:
log.Info("PID %d. Received SIGTSTP.", pid)
default:
log.Info("PID %d. Received %v.", pid, sig)
}
}
}
func (g *gracefulManager) doFork() error {
g.lock.Lock()
if g.forked {
g.lock.Unlock()
return errors.New("another process already forked. Ignoring this one")
}
g.forked = true
g.lock.Unlock()
// We need to move the file logs to append pids
setting.RestartLogsWithPIDSuffix()
_, err := RestartProcess()
return err
}
func (g *gracefulManager) RegisterServer() {
KillParent()
g.runningServerWaitGroup.Add(1)
}