HTTP 200 OK vs 412 Precondition Failed
HTTP 200 (OK) is a 2xx Success response, while 412 (Precondition Failed) is a 4xx Client Error response. 200 indicates that the request succeeded. The meaning depends on the HTTP method: GET returns the resource, POST reports the action result, HEAD returns headers only. In contrast, 412 means that one or more conditions in the request headers (If-Match, If-Unmodified-Since) evaluated to false.
คำอธิบาย
The request succeeded. The meaning depends on the HTTP method: GET returns the resource, POST reports the action result, HEAD returns headers only.
เมื่อคุณพบเห็น
The most common HTTP response — indicates the request was processed successfully.
วิธีแก้ไข
No fix needed. The request succeeded as expected.
คำอธิบาย
One or more conditions in the request headers (If-Match, If-Unmodified-Since) evaluated to false.
เมื่อคุณพบเห็น
When using conditional requests with ETags and the resource has changed.
วิธีแก้ไข
Refresh the ETag/Last-Modified value and retry with updated preconditions.
ความแตกต่างหลัก
200 is a 2xx Success response, while 412 is a 4xx Client Error response.
HTTP 200: The request succeeded. The meaning depends on the HTTP method: GET returns the resource, POST reports the action result, HEAD returns headers only.
HTTP 412: One or more conditions in the request headers (If-Match, If-Unmodified-Since) evaluated to false.
You encounter 200 when the most common HTTP response — indicates the request was processed successfully.
You encounter 412 when when using conditional requests with ETags and the resource has changed.
ควรใช้อันไหนเมื่อไร
For 200 (OK): No fix needed. The request succeeded as expected. For 412 (Precondition Failed): Refresh the ETag/Last-Modified value and retry with updated preconditions.