How do I know if a pointer is retrievable via SSP, or not?
Our producer API specification details which pointer types are available via which retrieval mechanisms. Most pointers on NRL point to unstructured PDFs that are retrievable via the Spine Secure Proxy.
At one point in time, SSP was the only retrieval mechanism in use, and consumers were advised that pointers with retrieval URLs prefixed with ssp://. Consumers could then transform ssp:// to https://.
We have since introduced a new retrieval mechanism extension called Extension-England-RetrievalMechanism. The lack of this extension on a pointer would mean that the pointer was created before the extension was introduced, meaning you’d have to check the prefix of the retrieval URL to determine if SSP should be used.