refactor, sketch SSE implementation

handlers/middleware.go

@@ -0,0 +1,25 @@
+package handlers
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/labstack/echo/v4"
+)
+
+func AuthMiddleware(next echo.HandlerFunc) echo.HandlerFunc {
+	return func(c echo.Context) error {
+		session, err := store.Get(c.Request(), "session")
+		if err != nil {
+			return c.String(http.StatusInternalServerError, "Error: Unable to retrieve session")
+		}
+		userID, ok := session.Values["user_id"]
+		if !ok {
+			fmt.Println("authMiddleware: session does not contain user_id. Redirect to /login")
+			// return c.String(http.StatusForbidden, "not logged in")
+			return c.Redirect(http.StatusSeeOther, "/login")
+		}
+		c.Set("user_id", userID)
+		return next(c)
+	}
+}