HTTP Status Codes
HTTP 412 Precondition Failed
412 Precondition Failed
The server rejected the request because one or more conditions defined by conditional request headers evaluated to false.
Error AtlasError Documentation and ResolutionObserved message
412 Precondition Failed
Why it happens
- The request included conditional headers such as If-Match or If-Unmodified-Since that no longer match the resource state.
- The client is attempting to update a stale version of a resource.
- Caching or optimistic concurrency controls are using outdated ETag or timestamp values.
How to fix it
- Fetch the latest representation of the resource and retry with current conditional values.
- Review If-Match, If-None-Match, and related headers for stale ETag or timestamp usage.
- Make sure optimistic concurrency logic refreshes resource state before issuing updates.
Official reference
MDN: 412 Precondition FailedRelated errors
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