public static async Task <string> GetOrCreateEssence(DemographicsDocument document, IDatabaseAsync database)
{
var keys = GetKeys(document);
var results = await Task.WhenAll(keys.Select(key => database.StringGetAsync(key)).ToArray());
var maybeMatches = results
.Zip(keys, (value, key) => new { Key = key, Value = value })
.ToLookup(x => x.Value.HasValue);
var essenceId = maybeMatches[true]
.Select(redisValue => (string)redisValue.Value)
.GroupBy(_ => _)
.OrderByDescending(valueGroup => valueGroup.Count())
.Select(valueGroup => valueGroup.Key)
.FirstOrDefault();
essenceId = essenceId ?? EssenceId.Create(document.DocumentId).ToString("N");
var unmatchedKeys = maybeMatches[false].Select(x => x.Key).ToArray();
await Task.WhenAll(unmatchedKeys.Select(key => database.StringSetAsync(key, essenceId)));
return(essenceId);
}
private static string[] GetKeys(DemographicsDocument document)
{
var demographicsToken = new[] { document.LastName, document.BirthDate.ToString("yyyyMMdd") }
.Select(value => value.ToLower())
.StringJoin("-");
return(new[]
{
new object[] { "record", document.RecordId.ToLower() },
new object[] { "session", document.SessionId.ToLower() },
new object[] { "demographics", demographicsToken }
}
.Select(formatArguments => string.Format(KeyFormat, formatArguments))
.ToArray());
}