4×× - Client Error

412 Precondition Failed

One or more conditions given in the request header fields evaluated to false when tested on the server.

This response code allows the client to place preconditions on the current resource state (its current representations and metadata) and, thus, prevent the request method from being applied if the target resource is in an unexpected state.

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• Source: RFC7232 Section 4.2

412 Code References

• Rails HTTP Status Symbol: :precondition_failed
• Go HTTP Status Constant: http.StatusPreconditionFailed
• Symfony HTTP Status Constant: Response::HTTP_PRECONDITION_FAILED
• Python2 HTTP Status Constant: httplib.PRECONDITION_FAILED
• Python3+ HTTP Status Constant: http.client.PRECONDITION_FAILED
• Python3.5+ HTTP Status Constant: http.HTTPStatus.PRECONDITION_FAILED