Client-side accessor preferences

[jselig-rigetti]

Related to #573

When selecting the best Accessor gRPC URL, the client should consider all possible Accessors of the target type (e.g. "gateway") and do a latency check in order to determine the best one to connection.

Separately, if a higher-preference Accessor cannot be connected to, subsequent options should be attempted. This will be important if the highest-priority Accessor does not allow ingress from a particular client.

[sarehaskari17]

Hi @jselig-rigetti, I’d be interested in looking into this and working on an implementation. Would you be happy for me to take this on?

[jselig-rigetti]

@sarehaskari17 Thank you for the offer - to me, this issue isn't quite as well described as I'd like it to be before asking anyone to take it on. Particularly how that latency check should be done, how often, if a connection failure should disqualify an accessor for use for the rest of the session, how this will all be configured by the user, etc.

Do you have a particular use case that you're trying to satisfy? That would help us develop the feature requirements against a concrete use-case.