public async Task <TEntity> SingleOrDefaultAsync(CancellationToken cancellationToken)
{
return(await Task.Run(() =>
{
cancellationToken.ThrowIfCancellationRequested();
var scan = PrepareScan();
var client = _pool.GetClient();
var scanner = client.scannerOpenWithScan(_tableName, scan, null);
var data = client.scannerGetList(scanner, _limit);
_pool.ReleaseClient(client);
return data;
}, cancellationToken)
.ContinueWith(x =>
{
cancellationToken.ThrowIfCancellationRequested();
if (x.Result.Count > 1)
{
throw new CommandException($"Expected 1 result, got {x.Result.Count}");
}
if (x.Result.Count == 0)
{
return default(TEntity);
}
var generator = new EntityGenerator <TEntity>(_map);
return generator.BuildEntity(x.Result.Single());
}, cancellationToken));
}
public async Task <TEntity> SingleOrDefaultAsync(CancellationToken cancellationToken)
{
// Cannot spawn an IO-Bound task because internal thrift limitation (does not expose any IO bound methods)
return(await Task.Run(() =>
{
cancellationToken.ThrowIfCancellationRequested();
var cols = ConvertToByteArrays(_columns);
var rows = ConvertToByteArrays(_rows);
var client = _pool.GetClient();
var data = client.getRowsWithColumns(_tableName, rows.Count > 0 ? rows : null,
cols.Count > 0 ? cols : null, null);
_pool.ReleaseClient(client);
return data;
}, cancellationToken)
.ContinueWith(x =>
{
cancellationToken.ThrowIfCancellationRequested();
if (x.Result.Count > 1)
{
throw new CommandException($"Expected 1 result, got {x.Result.Count}");
}
if (x.Result.Count == 0)
{
return default(TEntity);
}
var generator = new EntityGenerator <TEntity>(_map);
return generator.BuildEntity(x.Result.Single());
}, cancellationToken));
}
public TEntity SingleOrDefault()
{
var result = ExtractResult();
if (result.Count > 1)
{
throw new CommandException($"Expected 1 result, got {result.Count}");
}
if (result.Count == 0)
{
return(default(TEntity));
}
var generator = new EntityGenerator <TEntity>(_map);
return(generator.BuildEntity(result.Single()));
}