Golang api server

api-server/app/main.go

@@ -0,0 +1,77 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+
+	"github.com/gin-gonic/gin"
+)
+
+const ADDRESS = "0.0.0.0"
+const PORT = "3000"
+const LOG_FILE = "./log/api-server.log"
+
+var containerName string
+
+type HelloResponseDto struct {
+	Message string `json:"message"`
+}
+
+func handleHello(ctx *gin.Context) {
+	log.Println("Request received to handleHello")
+	ctx.JSON(
+		http.StatusOK,
+		HelloResponseDto{
+			Message: fmt.Sprintf("Hello world from %s", containerName),
+		},
+	)
+}
+
+func openLogFile(path string) (*os.File, error) {
+	logFile, err := os.OpenFile(path, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0644)
+	if err != nil {
+		return nil, err
+	}
+	return logFile, nil
+}
+
+func initLogging() {
+	file, err := openLogFile(LOG_FILE)
+	if err != nil {
+		log.Fatal(err)
+	}
+	log.SetOutput(file)
+	log.SetFlags(log.LstdFlags | log.Lshortfile | log.Lmicroseconds)
+}
+
+func main() {
+	// get container name from environment
+	containerName = os.Getenv("CONTAINER_NAME")
+	if len(containerName) == 0 {
+		containerName = "Unknown"
+	}
+
+	// get port from environment
+	port := os.Getenv("PORT")
+	if len(port) == 0 {
+		port = PORT
+	}
+
+	initLogging()
+
+	serverAddr := fmt.Sprintf("%s:%s", ADDRESS, port)
+
+	// init gin
+	gin.SetMode(gin.ReleaseMode)
+	router := gin.Default()
+	router.GET("/hello", handleHello)
+
+	msg := fmt.Sprintf("Running server on %s as %s", serverAddr, containerName)
+	log.Println(msg)
+	fmt.Printf("%s\n", msg)
+
+	// finally, start server
+	router.Run(serverAddr)
+}