private void ExecuteReduce(IEnumerable<IGrouping<dynamic, object>> groupedByReduceKey, WriteBatch writeBatch)
{
foreach (var grouping in groupedByReduceKey)
{
string reduceKey = grouping.Key;
Slice key = "results/" + _name + "/" + reduceKey;
var groupedResults = GetItemsToReduce(reduceKey, key, grouping);
var robustEnumerator = new RobustEnumerator2(_aggregationEngine.CancellationToken, 50)
{
OnError = (exception, o) =>
Log.WarnException("Could not process reduce for aggregation " + _name + Environment.NewLine + o,
exception)
};
var reduceResults =
robustEnumerator.RobustEnumeration(groupedResults.GetEnumerator(), _generator.ReduceDefinition).ToArray();
RavenJToken finalResult;
switch (reduceResults.Length)
{
case 0:
Log.Warn("FLYING PIGS!!! Could not find any results for a reduce on key {0} for aggregator {1}. Should not happen", reduceKey, _name);
finalResult = new RavenJObject {{"Error", "Invalid reduce result was generated"}};
break;
case 1:
finalResult = RavenJObject.FromObject(reduceResults[0]);
break;
default:
finalResult = new RavenJArray(reduceResults.Select(RavenJObject.FromObject));
break;
}
finalResult.EnsureCannotBeChangeAndEnableSnapshotting();
_cache.Set(reduceKey, finalResult);
writeBatch.Put(key, AggregationEngine.RavenJTokenToStream(finalResult));
}
}
