Add Gin framework and create REST API endpoints

main.go

@@ -1,23 +1,87 @@
 package main
 
 import (
-	"fmt"
 	"net/http"
 	"os"
+
+	"github.com/gin-gonic/gin"
 )
 
 const version = "1.0.0"
 
 func main() {
-	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprintf(w, "Hello, World! (Version %s)\n", version)
+	// Set Gin mode
+	gin.SetMode(gin.ReleaseMode)
+
+	// Create router
+	r := gin.Default()
+
+	// Add middleware for CORS
+	r.Use(func(c *gin.Context) {
+		c.Header("Access-Control-Allow-Origin", "*")
+		c.Header("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS")
+		c.Header("Access-Control-Allow-Headers", "Origin, Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token, Authorization")
+
+		if c.Request.Method == "OPTIONS" {
+			c.AbortWithStatus(http.StatusNoContent)
+			return
+		}
+
+		c.Next()
 	})
 
+	// Health check endpoint
+	r.GET("/health", func(c *gin.Context) {
+		c.JSON(http.StatusOK, gin.H{
+			"status":  "ok",
+			"version": version,
+		})
+	})
+
+	// Main endpoint
+	r.GET("/", func(c *gin.Context) {
+		c.JSON(http.StatusOK, gin.H{
+			"message": "Hello, World!",
+			"version": version,
+		})
+	})
+
+	// API endpoints
+	api := r.Group("/api/v1")
+	{
+		api.GET("/info", func(c *gin.Context) {
+			c.JSON(http.StatusOK, gin.H{
+				"service": "hello-api",
+				"version": version,
+				"status":  "running",
+			})
+		})
+
+		api.POST("/echo", func(c *gin.Context) {
+			var request struct {
+				Message string `json:"message"`
+			}
+
+			if err := c.ShouldBindJSON(&request); err != nil {
+				c.JSON(http.StatusBadRequest, gin.H{
+					"error": "Invalid JSON",
+				})
+				return
+			}
+
+			c.JSON(http.StatusOK, gin.H{
+				"echo":    request.Message,
+				"version": version,
+			})
+		})
+	}
+
+	// Get port from environment or use default
 	port := os.Getenv("PORT")
 	if port == "" {
 		port = "8080"
 	}
 
-	fmt.Printf("Server starting on port %s...\n", port)
-	http.ListenAndServe(":"+port, nil)
-}
+	// Start server
+	r.Run(":" + port)
+}