RateLimitException Handling fails

[ian-gavurin]

A long standing solution using this library seems to be failing to handle RateLimit violations.
It has explicit (tested and previously working) handling which makes use of FitbitRateLimitException when its thrown from FitbitClient.HandleResponse.

However, the response I'm currently seeing isn't compatible with the ApiError type, so can't be deserialised, and throws from JsonDotNetSerializer.
{ "error": { "code": 429, "message": "Resource has been exhausted (e.g. check quota).", "status": "RESOURCE_EXHAUSTED" } }
It also seems the "Retry-After" header isn't present, so the 429 handler would be ignored anyway.

What I'm not sure about is when this broke - as mentioned above, this used to work, so I'm not sure if something has changed in the API response? Fitbit documentation doesn't seem indicate this response should be different to other errors...

[Updated after a bit more digging]

[ian-gavurin]

I've been doing some testing around the error handling today.

It seems it's not just the rate limit which is now incompatible.

403 (Forbidden) also seems to be coming through in this format:
{ "error": { "code": 403, "message": "The caller does not have permission", "status": "PERMISSION_DENIED" } }

I've raised it with Fitibt https://community.fitbit.com/t5/Web-API-Development/Bug-quot-401-Unauthorized-quot-error-has-changed/m-p/5643762#M16509.