feature: add systemd notify

For the case that systemctl start pouch, we need to make sure that the pouchd has been started successfully. We cannot rely on the exit code of systemctl only, we need to use NOTIFY_SOCKET to send the state to the systemd. Signed-off-by: Eric Li <[email protected]>
AliyunContainerService · Jun 22, 2018 · 270bbc5 · 270bbc5
1 parent 8b1f8f3
commit 270bbc5
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Showing 17 changed files with 1,063 additions and 8 deletions.
diff --git a/apis/server/server.go b/apis/server/server.go
@@ -34,7 +34,7 @@ type Server struct {
 }
 
 // Start setup route table and listen to specified address which currently only supports unix socket and tcp address.
-func (s *Server) Start() (err error) {
+func (s *Server) Start(readyCh chan bool) (err error) {
 	router := initRoute(s)
 	errCh := make(chan error)
 
@@ -50,6 +50,7 @@ func (s *Server) Start() (err error) {
 	if s.Config.TLS.Key != "" && s.Config.TLS.Cert != "" {
 		tlsConfig, err = httputils.GenTLSConfig(s.Config.TLS.Key, s.Config.TLS.Cert, s.Config.TLS.CA)
 		if err != nil {
+			readyCh <- false
 			return err
 		}
 		if s.Config.TLS.VerifyRemote {
@@ -61,6 +62,7 @@ func (s *Server) Start() (err error) {
 	for _, one := range s.Config.Listen {
 		l, err := getListener(one, tlsConfig)
 		if err != nil {
+			readyCh <- false
 			return err
 		}
 		logrus.Infof("start to listen to: %s", one)
@@ -71,6 +73,9 @@ func (s *Server) Start() (err error) {
 		}(l)
 	}
 
+	// the http server has set up, send Ready
+	readyCh <- true
+
 	// not error, will block and run forever.
 	return <-errCh
 }

diff --git a/cri/criservice.go b/cri/criservice.go
@@ -14,37 +14,42 @@ import (
 )
 
 // RunCriService start cri service if pouchd is specified with --enable-cri.
-func RunCriService(daemonconfig *config.Config, containerMgr mgr.ContainerMgr, imageMgr mgr.ImageMgr, stopCh chan error) {
+func RunCriService(daemonconfig *config.Config, containerMgr mgr.ContainerMgr, imageMgr mgr.ImageMgr, stopCh chan error, readyCh chan bool) {
 	var err error
 
 	defer func() {
 		stopCh <- err
 		close(stopCh)
 	}()
 	if !daemonconfig.IsCriEnabled {
+		// the CriService has been disabled, so send Ready
+		readyCh <- true
 		return
 	}
 	switch daemonconfig.CriConfig.CriVersion {
 	case "v1alpha1":
-		err = runv1alpha1(daemonconfig, containerMgr, imageMgr)
+		err = runv1alpha1(daemonconfig, containerMgr, imageMgr, readyCh)
 	case "v1alpha2":
-		err = runv1alpha2(daemonconfig, containerMgr, imageMgr)
+		err = runv1alpha2(daemonconfig, containerMgr, imageMgr, readyCh)
 	default:
+		readyCh <- false
 		err = fmt.Errorf("invalid CRI version,failed to start CRI service")
 	}
 	return
 }
 
 // Start CRI service with CRI version: v1alpha1
-func runv1alpha1(daemonconfig *config.Config, containerMgr mgr.ContainerMgr, imageMgr mgr.ImageMgr) error {
+func runv1alpha1(daemonconfig *config.Config, containerMgr mgr.ContainerMgr, imageMgr mgr.ImageMgr, readyCh chan bool) error {
 	logrus.Infof("Start CRI service with CRI version: v1alpha1")
 	criMgr, err := criv1alpha1.NewCriManager(daemonconfig, containerMgr, imageMgr)
 	if err != nil {
+		readyCh <- false
 		return fmt.Errorf("failed to get CriManager with error: %v", err)
 	}
 
 	service, err := servicev1alpha1.NewService(daemonconfig, criMgr)
 	if err != nil {
+		readyCh <- false
 		return fmt.Errorf("failed to start CRI service with error: %v", err)
 	}
 
@@ -59,6 +64,9 @@ func runv1alpha1(daemonconfig *config.Config, containerMgr mgr.ContainerMgr, ima
 		logrus.Infof("CRI Stream server stopped")
 	}()
 
+	// the criservice has set up, send Ready
+	readyCh <- true
+
 	// Check for error
 	for i := 0; i < cap(errChan); i++ {
 		if err := <-errChan; err != nil {
@@ -71,15 +79,17 @@ func runv1alpha1(daemonconfig *config.Config, containerMgr mgr.ContainerMgr, ima
 }
 
 // Start CRI service with CRI version: v1alpha2
-func runv1alpha2(daemonconfig *config.Config, containerMgr mgr.ContainerMgr, imageMgr mgr.ImageMgr) error {
+func runv1alpha2(daemonconfig *config.Config, containerMgr mgr.ContainerMgr, imageMgr mgr.ImageMgr, readyCh chan bool) error {
 	logrus.Infof("Start CRI service with CRI version: v1alpha2")
 	criMgr, err := criv1alpha2.NewCriManager(daemonconfig, containerMgr, imageMgr)
 	if err != nil {
+		readyCh <- false
 		return fmt.Errorf("failed to get CriManager with error: %v", err)
 	}
 
 	service, err := servicev1alpha2.NewService(daemonconfig, criMgr)
 	if err != nil {
+		readyCh <- false
 		return fmt.Errorf("failed to start CRI service with error: %v", err)
 	}
 
@@ -94,6 +104,9 @@ func runv1alpha2(daemonconfig *config.Config, containerMgr mgr.ContainerMgr, ima
 		logrus.Infof("CRI Stream server stopped")
 	}()
 
+	// the criservice has set up, send Ready
+	readyCh <- true
+
 	// Check for error
 	for i := 0; i < cap(errChan); i++ {
 		if err := <-errChan; err != nil {

diff --git a/daemon/daemon.go b/daemon/daemon.go
@@ -18,6 +18,8 @@ import (
 	"github.com/alibaba/pouch/pkg/meta"
 	"github.com/alibaba/pouch/pkg/system"
 
+	systemddaemon "github.com/coreos/go-systemd/daemon"
+	systemdutil "github.com/coreos/go-systemd/util"
 	"github.com/gorilla/mux"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
@@ -203,16 +205,30 @@ func (d *Daemon) Run() error {
 	// set image proxy
 	ctrd.SetImageProxy(d.config.ImageProxy)
 
+	httpReadyCh := make(chan bool)
+	criReadyCh := make(chan bool)
+
 	httpServerCloseCh := make(chan struct{})
 	go func() {
-		if err := d.server.Start(); err != nil {
+		if err := d.server.Start(httpReadyCh); err != nil {
 			logrus.Errorf("failed to start http server: %v", err)
 		}
 		close(httpServerCloseCh)
 	}()
 
 	criStopCh := make(chan error)
-	go criservice.RunCriService(d.config, d.containerMgr, d.imageMgr, criStopCh)
+	go criservice.RunCriService(d.config, d.containerMgr, d.imageMgr, criStopCh, criReadyCh)
+
+	httpReady := <-httpReadyCh
+	criReady := <-criReadyCh
+
+	if httpReady && criReady {
+		notifySystemd()
+	}
+
+	// close the ready channel
+	close(httpReadyCh)
+	close(criReadyCh)
 
 	err = <-criStopCh
 	if err != nil {
@@ -322,3 +338,18 @@ func (d *Daemon) addSystemLabels() error {
 
 	return nil
 }
+
+func notifySystemd() {
+	if !systemdutil.IsRunningSystemd() {
+		return
+	}
+
+	sent, err := systemddaemon.SdNotify(false, "READY=1")
+	if err != nil {
+		logrus.Errorf("failed to notify systemd for readiness: %v", err)
+	}
+
+	if !sent {
+		logrus.Errorf("forgot to set Type=notify in systemd service file?")
+	}
+}
diff --git a/hack/package/deb/systemd/pouch.service b/hack/package/deb/systemd/pouch.service
@@ -4,6 +4,7 @@ Description=pouch
 [Service]
 ExecStart=/usr/bin/pouchd
 ExecReload=/bin/kill -HUP $MAINPID
+Type=notify
 
 # Having non-zero Limit*s causes performance problems due to accounting overhead
 # in the kernel. We recommend using cgroups to do container-local accounting.

diff --git a/hack/package/rpm/service/pouch.service b/hack/package/rpm/service/pouch.service
@@ -4,6 +4,7 @@ Description=pouch
 [Service]
 ExecStart=/usr/local/bin/pouchd
 ExecReload=/bin/kill -HUP $MAINPID
+Type=notify
 
 # Having non-zero Limit*s causes performance problems due to accounting overhead
 # in the kernel. We recommend using cgroups to do container-local accounting.

diff --git a/vendor/github.com/coreos/go-systemd/LICENSE b/vendor/github.com/coreos/go-systemd/LICENSE
diff --git a/vendor/github.com/coreos/go-systemd/NOTICE b/vendor/github.com/coreos/go-systemd/NOTICE