New hook point before host lookup (aka BYOB -backend)
Problem
Currently the supported hosts database types are MySQL, PostgreSQL, and Cassandra. Support for additional datastores is not likely to be added anytime soon. It would be useful if a new hook point was added that would allow a custom hook to the retrieve host information via an external API call from any technology of their choosing, and supplement or even replace the internal host reservation lookup.
Proposed Solution
A new hook point, before or after “pkt4_receive” takes the request packet as input and receives one or more host reservation objects as output, to be used in addition to, or instead of, the internal host reservation. One or more flags can be used to control whether the internal host lookup is performed. This enhancement is probably made in conjunction with the “host-config” mode requested in the “Early host reservation lookup” enhancement.
(The RADIUS hook does this today.)