fix: give template default value

app/main.py

@@ -53,7 +53,16 @@ def get_xml_data(server: str, ticket_path: str):
 
 @app.get("/", response_class=HTMLResponse)
 async def index(request: Request):
-    return templates.TemplateResponse("index.html", {"request": request})
+    # 提供默认的 release_data 和 obtain_data
+    return templates.TemplateResponse(
+        "index.html",
+        {
+            "request": request,
+            "release_data": None,  # 默认值
+            "obtain_data": None,  # 默认值
+            "server": None,  # 默认服务器地址为空
+        },
+    )
 
 
 @app.post("/fetch", response_class=HTMLResponse)

app/templates/index.html

@@ -16,7 +16,7 @@
     </form>
     <br>
     <div align="center">
-        {% if obtain_data.response_code == "" %}
+        {% if obtain_data.response_code | default ("") == "" %}
         <h3> Please input your server to check. </h3>
         {% elif obtain_data.error %}
         <h3 style="color: red;">{{ obtain_data.error }}</h3> <!-- 显示错误信息 -->