Tries each route in the fixed order of PRV-2 and reports which one answered.
A route returns null when it has no answer and throws when it broke; both move on to
the next route, because a provider outage must not take down a feature that has a
rules fallback.
Tries each route in the fixed order of PRV-2 and reports which one answered.
A route returns null when it has no answer and throws when it broke; both move on to the next route, because a provider outage must not take down a feature that has a rules fallback.