core dump on failure to open file

[bhuffaker]

ipmeta_provider_netacq_edge_init: failed to open location file '/data/external/netacuity-dumps/Edge-processed/2018-08-03.netacq-4-locations.csv.gz'
python2: ipmeta.c:160: ipmeta_lookup: Assertion `provider != ((void *)0) && provider->enabled != 0' failed.
Aborted (core dumped)

[alistairking]

It's a programming error to try and do a lookup on a provider that failed to enable (i.e., this assert can only fire with incorrect code).
Since the lookup function is on the critical path for high-performance lookups, I'd actually be inclined to remove this assert altogether and let it fail in some other way.

But yeah, this is a little unfriendly when using the python bindings. Probably the best place to fix this is in pyipmeta since that will (should) never be used for super performance critical lookups (e.g., in traffic trace processing).