private static DnsSpamLookupResult FromStore(string tenant, string ipAddress)
        {
            var lookupServers = GetRblServers(tenant);
            var reverser      = new IpAddressReverser();
            var resolver      = new HostEntryResolver();
            var queryable     = new DnsQueryable(resolver);

            var lookup = new DnsSpamLookup(reverser, queryable, lookupServers);

            return(lookup.IsListedInSpamDatabase(ipAddress));
        }
        public void IsListedInSpamDatabaseTest(string ipAddress, bool isSpammer)
        {
            var lookupServers = new [] { "" };
            var reverser      = new IpAddressReverser();
            var resolver      = new FakeHostEntryResolver();
            var queryable     = new DnsQueryable(resolver);

            var lookup = new DnsSpamLookup(reverser, queryable, lookupServers);
            var result = lookup.IsListedInSpamDatabase(ipAddress);

            Assert.Equal(isSpammer, result.IsListed);
        }