feat(backend): implement custom middleware for session management and context handling

backend/middleware/auth.go

@@ -0,0 +1,40 @@
+package middleware
+
+import (
+	"github.com/gorilla/sessions"
+	"github.com/labstack/echo-contrib/session"
+	"github.com/labstack/echo/v4"
+	gonanoid "github.com/matoous/go-nanoid/v2"
+)
+
+// CustomMiddleware 创建自定义中间件
+func AuthMiddleware() echo.MiddlewareFunc {
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) error {
+			sess, err := session.Get("session", c)
+			if err != nil {
+				return err
+			}
+			sess.Options = &sessions.Options{
+				Path:     "/",
+				MaxAge:   86400 * 7,
+				HttpOnly: true,
+			}
+			if sess.Values["auth"] == nil {
+				id, err := gonanoid.New()
+				if err != nil {
+					return err
+				}
+				sess.Values["auth"] = id
+				if err := sess.Save(c.Request(), c.Response()); err != nil {
+					return err
+				}
+			}
+
+			cc := c.(*CustomContext)
+			cc.Auth = sess.Values["auth"]
+			// 将自定义上下文传递给下一个处理器
+			return next(cc)
+		}
+	}
+}

backend/middleware/context.go

@@ -0,0 +1,28 @@
+package middleware
+
+import (
+	"github.com/labstack/echo/v4"
+)
+
+// CustomContext 扩展 echo.Context 以添加自定义功能
+type CustomContext struct {
+	echo.Context
+	Auth interface{}
+}
+
+// NewCustomContext 创建自定义上下文的构造函数
+func NewCustomContext(c echo.Context) *CustomContext {
+	return &CustomContext{
+		Context: c,
+	}
+}
+
+// ContextMiddleware 中间件用于将标准 echo.Context 转换为 CustomContext
+func ContextMiddleware() echo.MiddlewareFunc {
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) error {
+			cc := NewCustomContext(c)
+			return next(cc)
+		}
+	}
+}

backend/middleware/session.go

@@ -0,0 +1,11 @@
+package middleware
+
+import (
+	"github.com/gorilla/sessions"
+	"github.com/labstack/echo-contrib/session"
+	"github.com/labstack/echo/v4"
+)
+
+func SessionMiddleware() echo.MiddlewareFunc {
+	return session.Middleware(sessions.NewCookieStore([]byte("secret")))
+}