public static async Task <Recorder> RecordAsync(this IReadOnlyStream stream)
{
var recorder = new Recorder();
await stream.ReadAsync(recorder).ConfigureAwait(false);
return(recorder);
}
async Task CopyAsync(
IReadOnlyStream source,
IWriteOnlyStream destination,
CancellationToken cancellationToken = default)
{
byte[] buffer = this._bufferPool.Rent(4096);
try
{
int bytesRead;
while ((bytesRead = await source
.ReadAsync(buffer, 0, buffer.Length, cancellationToken)
.ConfigureAwait(false)) != 0)
{
// Transform
await destination
.WriteAsync(buffer, 0, bytesRead, cancellationToken)
.ConfigureAwait(false);
}
}
finally
{
this._bufferPool.Return(buffer);
}
}
public async Task <TResult> RunAsync <TResult>(IPayloadProcessor processor, CancellationToken cancellationToken)
where TResult : new()
{
long startIndex = 1;
TResult state = default(TResult);
string snapshotId = this._source.Id + "/" + typeof(TResult).Name;
if (_snapshots != null)
{
var si = await LoadSnapshot(snapshotId, cancellationToken).ConfigureAwait(false);
if (si != null)
{
state = (TResult)si.Payload;
if (_upToIndex.HasValue && si.SourceVersion == _upToIndex.Value)
{
return(state);
}
startIndex = si.SourceVersion + 1;
}
}
if (state == null)
{
state = new TResult();
}
var reducer = new Reducer <TResult>(state, _onMissing, processor);
await _source.ReadAsync(reducer, startIndex, _upToIndex ?? long.MaxValue, cancellationToken)
.ConfigureAwait(false);
if (_snapshots != null && reducer.LastIndex > 0)
{
await _snapshots.AddAsync(snapshotId, new SnapshotInfo(
_source.Id,
reducer.LastIndex,
state,
"1"
)).ConfigureAwait(false);
}
return(state);
}
public static Task ReadAsync(this IReadOnlyStream stream, ChunkProcessor fn)
{
return(stream.ReadAsync(new LambdaSubscription(fn), 0, long.MaxValue, CancellationToken.None));
}
public static Task ReadAsync(this IReadOnlyStream stream, ISubscription subscription, long fromIndexInclusive, long toIndexInclusive)
{
return(stream.ReadAsync(subscription, fromIndexInclusive, toIndexInclusive, CancellationToken.None));
}
public static Task ReadAsync(this IReadOnlyStream stream, ISubscription subscription, long fromIndexInclusive, CancellationToken cancellationToken)
{
return(stream.ReadAsync(subscription, fromIndexInclusive, long.MaxValue, cancellationToken));
}
public static Task ReadAsync(this IReadOnlyStream stream, ISubscription subscription)
{
return(stream.ReadAsync(subscription, 0, long.MaxValue, CancellationToken.None));
}