4×× Client Error
405 Method Not Allowed
The method received in the request-line is known by the origin server but not supported by the target resource.
The origin server MUST generate an Allow header field in a 405 response containing a list of the target resource's currently supported methods.
A 405 response is cacheable by default; i.e., unless otherwise indicated by the method definition or explicit cache controls1.
405 Code References
Rails HTTP Status Symbol
Go HTTP Status Constant
Symfony HTTP Status Constant
Python2 HTTP Status Constant
Python3+ HTTP Status Constant
Python3.5+ HTTP Status Constant