From e27ddf2cdf3c8b9d645de9d502a453abd5aef6b0 Mon Sep 17 00:00:00 2001
From: YueGuobin <yueguobin@outlook.com>
Date: Sun, 22 Feb 2026 23:43:47 +0800
Subject: [PATCH] feat(api): fix ETag handling and JSON serialization in
 template endpoint

- Use `default=str` in `json.dumps` to handle non-serializable objects
- Return proper HTTP 304 response with ETag header instead of raising exception
- Ensure consistent ETag generation for template caching
---
 gns3server/api/routes/controller/templates.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gns3server/api/routes/controller/templates.py b/gns3server/api/routes/controller/templates.py
index 4594fd635..edaf9692d 100644
--- a/gns3server/api/routes/controller/templates.py
+++ b/gns3server/api/routes/controller/templates.py
@@ -88,10 +88,10 @@ async def get_template(
 
     request_etag = request.headers.get("If-None-Match", "")
     template = await TemplatesService(templates_repo).get_template(template_id)
-    data = json.dumps(template)
+    data = json.dumps(template, default=str)
     template_etag = '"' + hashlib.md5(data.encode()).hexdigest() + '"'
     if template_etag == request_etag:
-        raise HTTPException(status_code=status.HTTP_304_NOT_MODIFIED)
+        return Response(status_code=status.HTTP_304_NOT_MODIFIED, headers={"ETag": template_etag})
     else:
         response.headers["ETag"] = template_etag
         return template