HTTP

HTTP 103 Early Hints vs 412 Precondition Failed

HTTP 103 (Early Hints) is a 1xx Informational response, while 412 (Precondition Failed) is a 4xx Client Error response. 103 indicates that used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response. In contrast, 412 means that one or more conditions in the request headers (If-Match, If-Unmodified-Since) evaluated to false.

Mô tả

Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.

Khi bạn thấy mã này

When a server wants the browser to start loading CSS/JS before the full response is ready.

Cách khắc phục

No fix needed. This optimization helps speed up page loading.

Mô tả

One or more conditions in the request headers (If-Match, If-Unmodified-Since) evaluated to false.

Khi bạn thấy mã này

When using conditional requests with ETags and the resource has changed.

Cách khắc phục

Refresh the ETag/Last-Modified value and retry with updated preconditions.

Sự khác biệt chính

1.

103 is a 1xx Informational response, while 412 is a 4xx Client Error response.

2.

HTTP 103: Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.

3.

HTTP 412: One or more conditions in the request headers (If-Match, If-Unmodified-Since) evaluated to false.

4.

You encounter 103 when when a server wants the browser to start loading CSS/JS before the full response is ready.

5.

You encounter 412 when when using conditional requests with ETags and the resource has changed.

Khi nào dùng cái nào

For 103 (Early Hints): No fix needed. This optimization helps speed up page loading. For 412 (Precondition Failed): Refresh the ETag/Last-Modified value and retry with updated preconditions.

Tìm hiểu thêm