Remove tasks and containers on SIGINT/SIGTERM

* Cleans-up and removes faasd containers/tasks when receiving
SIGINT/SIGTERM

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Gopkg.lock

@@ -440,6 +440,7 @@
   analyzer-name = "dep"
   analyzer-version = 1
   input-imports = [
+    "github.com/alexellis/go-execute",
     "github.com/containerd/containerd",
     "github.com/containerd/containerd/cio",
     "github.com/containerd/containerd/containers",
@@ -451,6 +452,7 @@
     "github.com/spf13/cobra",
     "github.com/vishvananda/netlink",
     "github.com/vishvananda/netns",
+    "golang.org/x/sys/unix",
   ]
   solver-name = "gps-cdcl"
   solver-version = 1

Gopkg.toml

@@ -1,30 +1,3 @@
-# Gopkg.toml example
-#
-# Refer to https://golang.github.io/dep/docs/Gopkg.toml.html
-# for detailed Gopkg.toml documentation.
-#
-# required = ["github.com/user/thing/cmd/thing"]
-# ignored = ["github.com/user/project/pkgX", "bitbucket.org/user/project/pkgA/pkgY"]
-#
-# [[constraint]]
-#   name = "github.com/user/project"
-#   version = "1.0.0"
-#
-# [[constraint]]
-#   name = "github.com/user/project2"
-#   branch = "dev"
-#   source = "github.com/myfork/project2"
-#
-# [[override]]
-#   name = "github.com/x/y"
-#   version = "2.4.0"
-#
-# [prune]
-#   non-go = false
-#   go-tests = true
-#   unused-packages = true
-
-
 [[constraint]]
   name = "github.com/containerd/containerd"
   version = "1.3.2"
@@ -37,6 +10,11 @@
   name = "github.com/spf13/cobra"
   version = "0.0.5"
 
+
+[[constraint]]
+  name = "github.com/alexellis/go-execute"
+  version = "0.3.0"
+
 [prune]
   go-tests = true
   unused-packages = true

cmd/install.go

@@ -0,0 +1,75 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+	"path"
+
+	systemd "github.com/alexellis/faasd/pkg/systemd"
+
+	"github.com/spf13/cobra"
+)
+
+var installCmd = &cobra.Command{
+	Use:   "install",
+	Short: "Install faasd",
+	RunE:  runInstall,
+}
+
+func runInstall(_ *cobra.Command, _ []string) error {
+
+	err := binExists("/usr/local/bin/", "faas-containerd")
+	if err != nil {
+		return err
+	}
+
+	err = binExists("/usr/local/bin/", "netns")
+	if err != nil {
+		return err
+	}
+
+	err = systemd.InstallUnit("faas-containerd")
+	if err != nil {
+		return err
+	}
+
+	err = systemd.InstallUnit("faasd")
+	if err != nil {
+		return err
+	}
+
+	err = systemd.DaemonReload()
+	if err != nil {
+		return err
+	}
+
+	err = systemd.Enable("faas-containerd")
+	if err != nil {
+		return err
+	}
+
+	err = systemd.Enable("faasd")
+	if err != nil {
+		return err
+	}
+
+	err = systemd.Start("faas-containerd")
+	if err != nil {
+		return err
+	}
+
+	err = systemd.Start("faasd")
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func binExists(folder, name string) error {
+	findPath := path.Join(folder, name)
+	if _, err := os.Stat(findPath); err != nil {
+		return fmt.Errorf("unable to stat %s, install this binary before continuing", findPath)
+	}
+	return nil
+}

cmd/root.go

@@ -22,6 +22,7 @@ const WelcomeMessage = "Welcome to faasd"
 func init() {
 	rootCommand.AddCommand(versionCmd)
 	rootCommand.AddCommand(upCmd)
+	rootCommand.AddCommand(installCmd)
 }
 
 var rootCommand = &cobra.Command{

cmd/up.go

@@ -1,9 +1,13 @@
 package cmd
 
 import (
+	"fmt"
 	"log"
 	"os"
+	"os/signal"
 	"path"
+	"sync"
+	"syscall"
 	"time"
 
 	"github.com/alexellis/faasd/pkg"
@@ -18,8 +22,57 @@ var upCmd = &cobra.Command{
 
 func runUp(_ *cobra.Command, _ []string) error {
 
+	services := makeServiceDefinitions()
+
+	start := time.Now()
+	supervisor, err := pkg.NewSupervisor("/run/containerd/containerd.sock")
+	if err != nil {
+		return err
+	}
+
+	log.Printf("Supervisor created in: %s\n", time.Since(start).String())
+
+	start = time.Now()
+
+	err = supervisor.Start(services)
+
+	if err != nil {
+		return err
+	}
+
+	defer supervisor.Close()
+
+	log.Printf("Supervisor init done in: %s\n", time.Since(start).String())
+
+	shutdownTimeout := time.Second * 1
+
+	wg := sync.WaitGroup{}
+	wg.Add(1)
+	go func() {
+		sig := make(chan os.Signal, 1)
+		signal.Notify(sig, syscall.SIGTERM, syscall.SIGINT)
+
+		log.Printf("faasd: waiting for SIGTERM or SIGINT\n")
+		<-sig
+
+		log.Printf("Signal received.. shutting down server in %s\n", shutdownTimeout.String())
+		err := supervisor.Remove(services)
+		if err != nil {
+			fmt.Println(err)
+		}
+		time.AfterFunc(shutdownTimeout, func() {
+			wg.Done()
+		})
+	}()
+
+	wg.Wait()
+	return nil
+}
+
+func makeServiceDefinitions() []pkg.Service {
 	wd, _ := os.Getwd()
-	svcs := []pkg.Service{
+
+	return []pkg.Service{
 		pkg.Service{
 			Name:  "nats",
 			Env:   []string{""},
@@ -71,28 +124,4 @@ func runUp(_ *cobra.Command, _ []string) error {
 			Caps:   []string{"CAP_NET_RAW"},
 		},
 	}
-
-	start := time.Now()
-	supervisor, err := pkg.NewSupervisor("/run/containerd/containerd.sock")
-	if err != nil {
-		return err
-	}
-
-	log.Printf("Supervisor created in: %s\n", time.Since(start).String())
-
-	start = time.Now()
-
-	err = supervisor.Start(svcs)
-
-	if err != nil {
-		return err
-	}
-
-	defer supervisor.Close()
-
-	log.Printf("Supervisor init done in: %s\n", time.Since(start).String())
-
-	time.Sleep(time.Minute * 120)
-
-	return nil
 }

hack/faas-containerd.service

@@ -0,0 +1,12 @@
+[Unit]
+Description=faasd-containerd
+
+[Service]
+MemoryLimit=500M
+ExecStart=/usr/local/bin/faas-containerd
+Restart=on-failure
+RestartSec=10s
+WorkingDirectory=/usr/local/bin/
+
+[Install]
+WantedBy=multi-user.target

hack/faasd.service

@@ -0,0 +1,13 @@
+[Unit]
+Description=faasd
+After=faas-containerd.service
+
+[Service]
+MemoryLimit=500M
+ExecStart={{.Cwd}}/faasd up
+Restart=on-failure
+RestartSec=10s
+WorkingDirectory={{.Cwd}}
+
+[Install]
+WantedBy=multi-user.target

pkg/supervisor.go

@@ -44,6 +44,18 @@ func (s *Supervisor) Close() {
 	defer s.client.Close()
 }
 
+func (s *Supervisor) Remove(svcs []Service) error {
+	ctx := namespaces.WithNamespace(context.Background(), "default")
+
+	for _, svc := range svcs {
+		err := removeContainer(ctx, s.client, svc.Name)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func (s *Supervisor) Start(svcs []Service) error {
 	ctx := namespaces.WithNamespace(context.Background(), "default")
 
@@ -61,7 +73,7 @@ func (s *Supervisor) Start(svcs []Service) error {
 	images := map[string]containerd.Image{}
 
 	for _, svc := range svcs {
-		fmt.Printf("Preparing: %s\n", svc.Name)
+		fmt.Printf("Preparing: %s with image: %s\n", svc.Name, svc.Image)
 
 		img, err := prepareImage(ctx, s.client, svc.Image)
 		if err != nil {
@@ -70,7 +82,6 @@ func (s *Supervisor) Start(svcs []Service) error {
 		images[svc.Name] = img
 		size, _ := img.Size(ctx)
 		fmt.Printf("Prepare done for: %s, %d bytes\n", svc.Image, size)
-
 	}
 
 	for _, svc := range svcs {
@@ -78,37 +89,9 @@ func (s *Supervisor) Start(svcs []Service) error {
 
 		image := images[svc.Name]
 
-		container, containerErr := s.client.LoadContainer(ctx, svc.Name)
+		containerErr := removeContainer(ctx, s.client, svc.Name)
-
+		if containerErr != nil {
-		if containerErr == nil {
+			return containerErr
-			found := true
-			t, err := container.Task(ctx, nil)
-			if err != nil {
-				if errdefs.IsNotFound(err) {
-					found = false
-				} else {
-					return fmt.Errorf("unable to get task %s: ", err)
-				}
-			}
-
-			if found {
-				status, _ := t.Status(ctx)
-				fmt.Println("Status:", status.Status)
-
-				// if status.Status == containerd.Running {
-				log.Println("need to kill", svc.Name)
-				err := killTask(ctx, t)
-				if err != nil {
-					return fmt.Errorf("error killing task %s, %s, %s", container.ID(), svc.Name, err)
-				}
-				// }
-			}
-
-			err = container.Delete(ctx, containerd.WithSnapshotCleanup)
-			if err != nil {
-				return fmt.Errorf("error deleting container %s, %s, %s", container.ID(), svc.Name, err)
-			}
-
 		}
 
 		mounts := []specs.Mount{}
@@ -185,7 +168,7 @@ func (s *Supervisor) Start(svcs []Service) error {
 			return err
 		}
 
-		ip := getIP(container.ID(), task.Pid())
+		ip := getIP(newContainer.ID(), task.Pid())
 
 		hosts, _ := ioutil.ReadFile("hosts")
 
@@ -324,3 +307,37 @@ func killTask(ctx context.Context, task containerd.Task) error {
 
 	return err
 }
+
+func removeContainer(ctx context.Context, client *containerd.Client, name string) error {
+
+	container, containerErr := client.LoadContainer(ctx, name)
+
+	if containerErr == nil {
+		found := true
+		t, err := container.Task(ctx, nil)
+		if err != nil {
+			if errdefs.IsNotFound(err) {
+				found = false
+			} else {
+				return fmt.Errorf("unable to get task %s: ", err)
+			}
+		}
+
+		if found {
+			status, _ := t.Status(ctx)
+			fmt.Printf("Status of %s is: %s\n", name, status.Status)
+
+			log.Printf("Need to kill %s\n", name)
+			err := killTask(ctx, t)
+			if err != nil {
+				return fmt.Errorf("error killing task %s, %s, %s", container.ID(), name, err)
+			}
+		}
+
+		err = container.Delete(ctx, containerd.WithSnapshotCleanup)
+		if err != nil {
+			return fmt.Errorf("error deleting container %s, %s, %s", container.ID(), name, err)
+		}
+	}
+	return nil
+}

pkg/systemd/systemd.go

@@ -0,0 +1,100 @@
+package systemd
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"path/filepath"
+	"text/template"
+
+	execute "github.com/alexellis/go-execute/pkg/v1"
+)
+
+func Enable(unit string) error {
+	task := execute.ExecTask{Command: "systemctl",
+		Args:        []string{"enable", unit},
+		StreamStdio: false,
+	}
+
+	res, err := task.Execute()
+	if err != nil {
+		return err
+	}
+
+	if res.ExitCode != 0 {
+		return fmt.Errorf("error executing task %s %v, stderr: %s", task.Command, task.Args, res.Stderr)
+	}
+
+	return nil
+}
+
+func Start(unit string) error {
+	task := execute.ExecTask{Command: "systemctl",
+		Args:        []string{"start", unit},
+		StreamStdio: false,
+	}
+
+	res, err := task.Execute()
+	if err != nil {
+		return err
+	}
+
+	if res.ExitCode != 0 {
+		return fmt.Errorf("error executing task %s %v, stderr: %s", task.Command, task.Args, res.Stderr)
+	}
+
+	return nil
+}
+
+func DaemonReload() error {
+	task := execute.ExecTask{Command: "systemctl",
+		Args:        []string{"daemon-reload"},
+		StreamStdio: false,
+	}
+
+	res, err := task.Execute()
+	if err != nil {
+		return err
+	}
+
+	if res.ExitCode != 0 {
+		return fmt.Errorf("error executing task %s %v, stderr: %s", task.Command, task.Args, res.Stderr)
+	}
+
+	return nil
+}
+
+func InstallUnit(name string) error {
+
+	tmpl, err := template.ParseFiles("./hack/" + name + ".service")
+
+	wd, _ := os.Getwd()
+	var tpl bytes.Buffer
+	userData := struct {
+		Cwd string
+	}{
+		Cwd: wd,
+	}
+
+	err = tmpl.Execute(&tpl, userData)
+	if err != nil {
+		return err
+	}
+
+	err = writeUnit(name+".service", tpl.Bytes())
+
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func writeUnit(name string, data []byte) error {
+	f, err := os.Create(filepath.Join("/lib/systemd/system", name))
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	_, err = f.Write(data)
+	return err
+}