werkzeug.exceptions.PreconditionRequired

exception documentation

class PreconditionRequired(HTTPException): (source)

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*428* `Precondition Required` The server requires this request to be conditional, typically to prevent the lost update problem, which is a race condition between two or more clients attempting to update a resource through PUT or DELETE. By requiring each client to include a conditional header ("If-Match" or "If-Unmodified- Since") with the proper value retained from a recent GET request, the server ensures that each client has at least seen the previous revision of the resource.

Class Variable code Undocumented
Class Variable description Undocumented

Inherited from HTTPException:

Method __call__ Call the exception as WSGI application.
Method __init__ Undocumented
Method __repr__ Undocumented
Method __str__ Undocumented
Method get_body Get the HTML body.
Method get_description Get the description.
Method get_headers Get a list of headers.
Method get_response Get a response object. If one was passed to the exception it's returned directly.
Instance Variable response Undocumented
Property name The status name.