public static Tran WithDocuments(IEnumerable <Document> docs)
{
var tran = new Tran();
tran._docs.AddRange(docs);
return(tran);
}
public static Tran WithSingleDocument(Document doc)
{
var tran = new Tran();
tran.AddDocument(doc);
return(tran);
}
private async Task Recover()
{
var docIdInDataFile = await _dataFile.GetLastDocId();
var docsFromWal = await _wal.ReadDocsAfter(docIdInDataFile);
await _dataFile.Apply(Tran.WithDocuments(docsFromWal));
}
public async Task <DataFileCommitInfo> Apply(Tran tran)
{
foreach (var doc in tran.Documents)
{
_nonPersistedQ.Enqueue(doc);
}
return(await CommitIfRequired().ConfigureAwait(false));
}
private async Task CommitTran(Tran tran)
{
// persist in write ahead log
await _wal.CommitTran(tran).ConfigureAwait(false);
// add new records to datafile (it may not get committed to disk right away)
var commitInfo = await _dataFile.Apply(tran).ConfigureAwait(false);
if (commitInfo != null)
{
// some data was committed to datafile, need to update inverted index
await UpdateIndex(commitInfo.DocsByOffsets).ConfigureAwait(false);
await _wal.Checkpoint(commitInfo.LastCommittedDocId);
}
}
public async Task CommitTran(Tran tran)
{
await _commitLock.WaitAsync().ConfigureAwait(false);
try
{
using (Measured.Operation("wal_commit"))
{
foreach (var doc in tran.Documents)
{
doc.Id = _docIdGenerator.GetNextId();
}
await DocumentSerializer.SerializeBatch(tran.Documents, _file).ConfigureAwait(false);
await _file.FlushAsync().ConfigureAwait(false);
}
}
finally
{
_commitLock.Release();
}
}
public async Task AddDocuments(IReadOnlyCollection <Document> docs)
{
var tran = Tran.WithDocuments(docs);
await CommitTran(tran).ConfigureAwait(false);
}
public async Task AddDocument(Document doc)
{
var tran = Tran.WithSingleDocument(doc);
await CommitTran(tran).ConfigureAwait(false);
}