Which base64 standard should be used with URNs for forge apis?

Question

In the tutorial / docs of the model derivative API it is mentioned URNs should be urlsafe base64 encoded according to RCF 6920 but the spec is not mentioned in the full list of base64 variants also mentioned in the tutorial. Does the tutorial maybe refer to RCF 4648 or which standard should be used?

Sincerly,
Dominik

Answer 1

That's an interesting question. I've been using all sorts of ways to encode/decode base64 when working with the Forge Model Derivative service, for example:

• with base64 command on *nix systems
• with btoa JavaScript function in browsers
• with toString('base64') in Node.js
• with https://www.base64encode.org

If the documentation for these methods mentions anything, it's the RFC 4648, so I'd say that's the one, plus the URL safe encoding, meaning:

the "+" and "/" characters are respectively replaced by "-" and "_", and the padding "=" signs are omitted