feat: add signal handling serviceweaver config (#11)

Added signal handling for graceful process termination and set the 
SERVICEWEAVER_CONFIG environment variable if not already set. 
The feature enhances the run method by incorporating signal handling 
for gracefully closing the process upon receiving SIGINT, SIGKILL, 
or SIGTERM signals. Additionally, a comment with a TODO was included 
for potential future improvements. Also, Set MySQL driver in template 
for database connections

cmd/boneless/main.go

@@ -59,8 +59,8 @@ func init() {
 
 func main() {
 	flag.Usage = func() { fmt.Fprint(os.Stderr, usage) }
-
 	flag.Parse()
+
 	if len(flag.Args()) == 0 {
 		fmt.Fprint(os.Stderr, usage)
 		os.Exit(1)

internal/run.go

@@ -5,17 +5,29 @@ import (
 	"io/fs"
 	"os"
 	"os/exec"
+	"os/signal"
 	"path/filepath"
 	"syscall"
 	"time"
 )
 
+const msgRunning = `
+    __                           __                                ______    __     ____
+   / /_   ____    ____   ___    / /  ___    _____   _____         / ____/   / /    /  _/
+  / __ \ / __ \  / __ \ / _ \  / /  / _ \  / ___/  / ___/        / /       / /     / /  
+ / /_/ // /_/ / / / / //  __/ / /  /  __/ (__  )  (__  )        / /___    / /___ _/ /   
+/_.___/ \____/ /_/ /_/ \___/ /_/   \___/ /____/  /____/         \____/   /_____//___/  
+
+running...
+`
+
 func findMainFile() (filePath string) {
 	pwd, err := os.Getwd()
 	if err != nil {
 		panic(err)
 	}
 
+	// TODO: improve that to ensure that the file is the package main
 	_ = filepath.Walk(pwd, func(path string, info fs.FileInfo, _ error) error {
 		if !info.IsDir() {
 			if info.Name() == "main.go" {
@@ -30,6 +42,15 @@ func findMainFile() (filePath string) {
 
 func Start() {
 	mainFile := findMainFile()
+
+	// Set SERVICEWEAVER_CONFIG environment variable if not already set
+	if _, ok := os.LookupEnv("SERVICEWEAVER_CONFIG"); !ok {
+		err := os.Setenv("SERVICEWEAVER_CONFIG", "./weaver.toml")
+		if err != nil {
+			panic(fmt.Sprintf("failed to set env var SERVICEWEAVER_CONFIG: %s", err))
+		}
+	}
+
 	cmd := exec.Command("go", "run", mainFile)
 	cmd.SysProcAttr = &syscall.SysProcAttr{
 		Setpgid: true,
@@ -42,19 +63,25 @@ func Start() {
 		panic("cmd run failed: " + err.Error())
 	}
 	time.Sleep(time.Second)
-	fmt.Printf(`
-    __                           __                                ______    __     ____
-   / /_   ____    ____   ___    / /  ___    _____   _____         / ____/   / /    /  _/
-  / __ \ / __ \  / __ \ / _ \  / /  / _ \  / ___/  / ___/        / /       / /     / /  
- / /_/ // /_/ / / / / //  __/ / /  /  __/ (__  )  (__  )        / /___    / /___ _/ /   
-/_.___/ \____/ /_/ /_/ \___/ /_/   \___/ /____/  /____/         \____/   /_____//___/  
+	println(msgRunning)
 
-running...
-
- `)
+	go CloseBySignal(cmd.Process.Pid)
 
 	err = cmd.Wait()
 	if err != nil {
 		println(err.Error())
 	}
 }
+
+func CloseBySignal(pid int) {
+	println("PID:", pid)
+	ch := make(chan os.Signal, 1)
+	signal.Notify(ch, syscall.SIGINT, syscall.SIGKILL, syscall.SIGTERM)
+	select {
+	default:
+		switch <-ch {
+		case syscall.SIGINT, syscall.SIGKILL, syscall.SIGTERM:
+			syscall.Kill(-pid, syscall.SIGKILL)
+		}
+	}
+}

internal/tools.go

@@ -29,6 +29,7 @@ func ReadToml(componentName string) (qsConn string) {
 		panic(err)
 	}
 
+	// TODO: improve that same internal/run.go:46
 	weaverToml, err := ioutil.ReadFile(pwd + "/weaver.toml")
 	if err != nil {
 		panic(err)

internal/version.go

@@ -7,7 +7,7 @@ import (
 	"strings"
 )
 
-const Version = "v0.1.1"
+const Version = "v0.2.0"
 
 func ValidateLatestVersion() {
 	cmd := exec.Command("go", "list", "-m", "github.com/renanbastos93/boneless@latest")

templates/files/component.go.tpl

@@ -6,6 +6,7 @@ import (
 	"fmt"
 
 	"github.com/ServiceWeaver/weaver"
+	_ "github.com/go-sql-driver/mysql"
 	"{{.Module}}/internal/{{.ComponentName}}/store"
 )