public async Task <Stream> OpenReadAsync(SqlItem item)
{
if (item == null)
{
throw new ArgumentNullException(nameof(item));
}
if (item.Id == Guid.Empty)
{
throw new UnauthorizedAccessException();
}
using (var reader = await SqlExtensions.ExecuteReaderAsync(ConnectionString, "SELECT Data FROM Item WHERE Id = @id", new { id = item.Id }, Logger).ConfigureAwait(false))
{
if (!reader.Read())
{
return(null);
}
if (await reader.IsDBNullAsync(0))
{
return(null);
}
// it's a pitty GetFieldValueAsync<Stream> doesn't work... https://github.com/dotnet/runtime/issues/28596#issuecomment-484614943
return(reader.GetSqlBytes(0).Stream);
}
}
private async Task <bool> ExistsNameAsync(Guid parentId, string name)
{
using (var reader = await SqlExtensions.ExecuteReaderAsync(ConnectionString, "SELECT 1 FROM Item WHERE ParentId = @id AND Name=@name", new { id = parentId, name }, Logger).ConfigureAwait(false))
{
return(await reader.ReadAsync());
}
}
public async IAsyncEnumerable <IFileSystemEvent> EnumerateChangesAsync(DateTime startTime)
{
using (var reader = await SqlExtensions.ExecuteReaderAsync(ConnectionString, "SELECT Id, ItemId, ParentId, Type, CreationTimeUtc, OldName FROM Change WHERE CreationTimeUtc > @startTime", new { startTime = startTime.ToUniversalTime() }, Logger).ConfigureAwait(false))
{
while (reader.Read())
{
yield return(new Event(reader));
}
}
}
private async Task <SqlItem> GetSqlItemAsync(Guid parentId, string name)
{
using (var reader = await SqlExtensions.ExecuteReaderAsync(ConnectionString, "SELECT Id, ParentId, Name, LastAccessTimeUtc, CreationTimeUtc, LastWriteTimeUtc, Attributes, DATALENGTH(Data) AS Length FROM Item WHERE ParentId = @id AND Name=@name", new { id = parentId, name }, Logger).ConfigureAwait(false))
{
if (reader.Read())
{
return(NewItem(reader));
}
return(null);
}
}
public async IAsyncEnumerable <SqlItem> EnumerateAsync(SqlItem parentItem, EnumerateOptions options = null)
{
options ??= new EnumerateOptions();
string and;
if (options.IncludeFiles)
{
if (options.IncludeFolders)
{
and = null;
}
else
{
and = " AND (Attributes & " + (int)FileAttributes.Directory + ") = 0";
}
}
else
{
if (options.IncludeFolders)
{
and = " AND (Attributes & " + (int)FileAttributes.Directory + ") <> 0";
}
else
{
yield break;
}
}
if (!options.IncludeHidden)
{
and += " AND (Attributes & " + (int)FileAttributes.Hidden + ") = 0";
}
using (var reader = await SqlExtensions.ExecuteReaderAsync(ConnectionString, "SELECT Id, ParentId, Name, LastAccessTimeUtc, CreationTimeUtc, LastWriteTimeUtc, Attributes, DATALENGTH(Data) AS Length FROM Item WHERE ParentId = @id AND Id <> '00000000-0000-0000-0000-000000000000'" + and, new { id = parentItem.Id }, Logger).ConfigureAwait(false))
{
while (reader.Read())
{
yield return(NewItem(reader));
}
}
}