v3.0.0 (#18)

internal/pkg/pm2/pm2.go

@@ -0,0 +1,71 @@
+package pm2
+
+import (
+	"fmt"
+	"os/exec"
+
+	"github.com/thecodingmachine/gotenberg/internal/pkg/notify"
+)
+
+// Process is a type that can launch or
+// shutdown a process with PM2.
+type Process interface {
+	Launch() error
+	Shutdown() error
+	getArgs() []string
+	getName() string
+	getFullname() string
+	isViable() bool
+	warmup()
+}
+
+const maxRestartAttempts int = 5
+
+var humanNames = map[string]string{
+	"start":   "started",
+	"restart": "restarted",
+	"stop":    "stopped",
+}
+
+func launch(p Process) error {
+	if err := run(p, "start"); err != nil {
+		return err
+	}
+	p.warmup()
+	if !p.isViable() {
+		attempts := 0
+		for attempts < maxRestartAttempts && !p.isViable() {
+			run(p, "restart")
+			p.warmup()
+			attempts++
+		}
+		if !p.isViable() {
+			return fmt.Errorf("failed to launch %s", p.getFullname())
+		}
+	}
+	return nil
+}
+
+func shutdown(p Process) error {
+	return run(p, "stop")
+}
+
+func run(p Process, cmdName string) error {
+	cmdArgs := []string{
+		cmdName,
+		p.getName(),
+	}
+	if cmdName == "start" {
+		cmdArgs = append(cmdArgs, "--interpreter none", "--")
+		cmdArgs = append(cmdArgs, p.getArgs()...)
+	}
+	cmd := exec.Command(
+		"pm2",
+		cmdArgs...,
+	)
+	if err := cmd.Start(); err != nil {
+		return fmt.Errorf("%s %s with PM2: %v", cmdName, p.getFullname(), err)
+	}
+	notify.Println(fmt.Sprintf("%s %s with PM2", p.getFullname(), humanNames[cmdName]))
+	return nil
+}