private async Task ReadAndUpdateSystemConfig()
{
Slice configKey = "system/config";
SystemConfig systemConfig;
using (var stream = _storage.Reader.Read(configKey))
{
systemConfig = stream != null
? new JsonSerializer().Deserialize<SystemConfig>(new JsonTextReader(new StreamReader(stream)))
: new SystemConfig();
systemConfig.EtagBase++;
_sequentialUuidGenerator.EtagBase = systemConfig.EtagBase;
}
var writeBatch = new WriteBatch();
writeBatch.Put(configKey, SmallObjectToMemoryStream(systemConfig));
await _storage.Writer.WriteAsync(writeBatch);
}
public async Task<Etag> AppendAsync(string topic, IEnumerable<RavenJObject> items)
{
if (items == null)
return null;
var batch = new WriteBatch();
Etag etag = null;
foreach (var item in items)
{
RavenJToken metadata;
if (item.TryGetValue("@metadata", out metadata) == false)
item["@metadata"] = metadata = new RavenJObject();
((RavenJObject)metadata)["Raven-Entity-Name"] = topic;
etag = GetNextEtag();
Slice key = "events/" + etag;
batch.Put(key, RavenJTokenToStream(item));
}
await _storage.Writer.WriteAsync(batch);
_appendEvent.PulseAll();
return etag;
}
public async Task CreateAggregationAsync(IndexDefinition indexDefinition)
{
var dynamicViewCompiler = new DynamicViewCompiler(indexDefinition.Name, indexDefinition, Path.Combine(_path, "Generators"));
var generator = dynamicViewCompiler.GenerateInstance();
var writeBatch = new WriteBatch();
var memoryStream = SmallObjectToMemoryStream(indexDefinition);
writeBatch.Put("aggregators/" + indexDefinition.Name, memoryStream);
await _storage.Writer.WriteAsync(writeBatch);
var aggregator = new Aggregator(this, indexDefinition.Name, generator);
_aggregations.AddOrUpdate(indexDefinition.Name, aggregator, (s, viewGenerator) => aggregator);
Background.Work(aggregator.StartAggregation);
}
internal static IEnumerable<LogReadResult> ReadFromLog(Stream logFile, BufferPool bufferPool)
{
var logReader = new LogReader(logFile, true, 0, bufferPool);
Stream logRecordStream;
while (logReader.TryReadRecord(out logRecordStream))
{
var batch = new WriteBatch();
ulong seq;
using (logRecordStream)
{
var buffer = new byte[8];
logRecordStream.ReadExactly(buffer, 8);
seq = BitConverter.ToUInt64(buffer, 0);
logRecordStream.ReadExactly(buffer, 4);
var opCount = BitConverter.ToInt32(buffer, 0);
for (var i = 0; i < opCount; i++)
{
logRecordStream.ReadExactly(buffer, 1);
var op = (Operations)buffer[0];
var keyCount = logRecordStream.Read7BitEncodedInt();
var array = new byte[keyCount];
logRecordStream.ReadExactly(array, keyCount);
var key = new Slice(array);
switch (op)
{
case Operations.Delete:
batch.Delete(key);
break;
case Operations.Put:
logRecordStream.ReadExactly(buffer, 4);
var size = BitConverter.ToInt64(buffer, 0);
var value = new MemoryStream();
logRecordStream.CopyTo(value, size, LogWriter.BlockSize);
batch.Put(key, value);
break;
default:
throw new ArgumentException("Invalid operation type: " + op);
}
}
}
yield return new LogReadResult
{
WriteSequence = seq,
WriteBatch = batch
};
}
}
private async Task AggregateAsync()
{
var lastAggregatedEtag = (Etag) _lastAggregatedEtag;
while (_aggregationEngine.CancellationToken.IsCancellationRequested == false)
{
var eventDatas = _aggregationEngine.Events(lastAggregatedEtag).Take(1024)
.ToArray();
if (eventDatas.Length == 0)
{
await _aggregationEngine.WaitForAppendAsync(_appendEventState);
continue;
}
try
{
var items = eventDatas.Select(x => new DynamicJsonObject(x.Data)).ToArray();
var writeBatch = new WriteBatch();
var groupedByReduceKey = ExecuteMaps(items);
ExecuteReduce(groupedByReduceKey, writeBatch);
lastAggregatedEtag = eventDatas.Last().Etag;
var status = new RavenJObject {{"@etag", lastAggregatedEtag.ToString()}};
writeBatch.Put(_aggStat, AggregationEngine.RavenJTokenToStream(status));
await _aggregationEngine.Storage.Writer.WriteAsync(writeBatch);
}
catch (Exception e)
{
Log.ErrorException("Could not process aggregation", e);
throw;
}
finally
{
Thread.VolatileWrite(ref _lastAggregatedEtag, lastAggregatedEtag);
_aggregationCompleted.PulseAll();
}
}
}
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));
}
}