Initial backend repository commit.

Set up project files and add .gitignore to exclude local build/runtime artifacts.

Made-with: Cursor

internal/middleware/cors.go

@@ -0,0 +1,46 @@
+package middleware
+
+import (
+	"log"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+)
+
+// CORS CORS中间件
+func CORS() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		// 获取请求路径
+		path := c.Request.URL.Path
+
+		c.Header("Access-Control-Allow-Origin", "*")
+		c.Header("Access-Control-Allow-Methods", "GET, POST, PUT, PATCH, DELETE, OPTIONS")
+		// 添加 WebSocket 升级所需的头
+		c.Header("Access-Control-Allow-Headers", "Origin, Content-Type, Accept, Authorization, Connection, Upgrade, Sec-WebSocket-Key, Sec-WebSocket-Version, Sec-WebSocket-Protocol, Sec-WebSocket-Extensions")
+		c.Header("Access-Control-Expose-Headers", "Content-Length, Connection, Upgrade")
+		c.Header("Access-Control-Allow-Credentials", "true")
+
+		// 处理 WebSocket 升级请求的预检
+		if c.Request.Method == "OPTIONS" {
+			log.Printf("[CORS] OPTIONS 预检请求: %s", path)
+			c.AbortWithStatus(204)
+			return
+		}
+
+		// 针对 WebSocket 路径的特殊处理
+		if path == "/ws" {
+			connection := c.GetHeader("Connection")
+			upgrade := c.GetHeader("Upgrade")
+			log.Printf("[CORS] WebSocket 请求: Connection=%s, Upgrade=%s", connection, upgrade)
+
+			// 检查是否是有效的 WebSocket 升级请求
+			if strings.Contains(strings.ToLower(connection), "upgrade") && strings.ToLower(upgrade) == "websocket" {
+				log.Printf("[CORS] 有效的 WebSocket 升级请求")
+			} else {
+				log.Printf("[CORS] 警告: 不是有效的 WebSocket 升级请求!")
+			}
+		}
+
+		c.Next()
+	}
+}