308 PERMANENT REDIRECT
The target resource has been assigned a new permanent URI and any future references to this resource ought to use one of the enclosed URIs.
Clients with link editing capabilities ought to automatically re-link references to the effective request URI1 to one or more of the new references sent by the server, where possible.
The server SHOULD generate a Location header field in the response containing a preferred URI reference for the new permanent URI. The user agent MAY use the Location field value for automatic redirection. The server’s response payload usually contains a short hypertext note with a hyperlink to the new URI(s).
A 308 response is cacheable by default; i.e., unless otherwise indicated by the method definition or explicit cache controls.
Note: This status code is similar to 301 Moved Permanently, except that it does not allow changing the request method from POST to GET.
Effective Request URI RFC7230 Section 5.5
Location RFC7231 Section 7.1.2
Calculating Heuristic Freshness RFC7234 Section 4.2.2
308 PERMANENT REDIRECT Source: RFC738 Section 3
308 CODE REFERENCES
Symfony HTTP Status Constant