project init

Author: norbertwagner

app/main.go

@@ -0,0 +1,9 @@
+package main
+
+import "fmt"
+
+func main() {
+	fmt.Println("Hello World! 1")
+	fmt.Println("Hello World! 2")
+	fmt.Println("Hello World! 3")
+}

go.mod

@@ -0,0 +1,3 @@
+module godemon
+
+go 1.15

main.go

@@ -0,0 +1,54 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"time"
+)
+
+func watchFile(filePath string) error {
+	initialStat, err := os.Stat(filePath)
+	if err != nil {
+		return err
+	}
+
+	for {
+		stat, err := os.Stat(filePath)
+		if err != nil {
+			return err
+		}
+
+		if stat.Size() != initialStat.Size() || stat.ModTime() != initialStat.ModTime() {
+			break
+		}
+
+		time.Sleep(1 * time.Second)
+	}
+
+	return nil
+}
+
+func main() {
+	doneChan := make(chan bool)
+	for true {
+		go func(doneChan chan bool) {
+			defer func() {
+				doneChan <- true
+			}()
+
+			err := watchFile("./app/main.go")
+			if err != nil {
+				fmt.Println(err)
+			}
+
+			fmt.Println("File has been changed")
+			cmd := exec.Command("go", "run", "./app/main.go")
+			cmd.Stdout = os.Stdout
+			cmd.Stderr = os.Stderr
+			cmd.Run()
+		}(doneChan)
+
+		<-doneChan
+	}
+}