/// <summary>
/// Applies given media storage <paramref name="item"/> to <paramref name="media"/> entity as blob.
/// </summary>
/// <param name="media">Media item</param>
/// <param name="item">The source item</param>
/// <param name="save">Whether to commit changes to <paramref name="media"/> entity to database immediately.</param>
public async Task ApplyBlobAsync(IMediaAware media, MediaStorageItem item, bool save = false)
{
Guard.NotNull(media, nameof(media));
if (item == null)
{
media.ApplyBlob(null);
if (save)
{
await _db.SaveChangesAsync();
}
return;
}
using (item)
{
if (_db.DataProvider.CanStreamBlob)
{
await SaveFast(media, item);
}
else
{
// BLOB stream unsupported
var buffer = await item.SourceStream.ToByteArrayAsync();
media.ApplyBlob(buffer);
media.Size = buffer.Length;
if (save)
{
await _db.SaveChangesAsync();
}
}
}
}
public override async Task SaveToAsync(Stream stream, IMediaAware media)
{
if (stream.CanSeek)
{
stream.SetLength(0);
}
await SourceStream.CopyToAsync(stream);
if (stream.CanSeek)
{
stream.Position = 0;
}
media.Size = (int)stream.Length;
}
/// <summary>
/// Applies Blob to file
/// </summary>
/// <param name="blob">The file binary (can be null)</param>
public static void ApplyBlob(this IMediaAware media, byte[] blob)
{
Guard.NotNull(media, nameof(media));
if (blob == null || blob.LongLength == 0)
{
media.MediaStorageId = null;
media.MediaStorage = null;
}
else
{
if (media.MediaStorage != null)
{
media.MediaStorage.Data = blob;
}
else
{
media.MediaStorage = new MediaStorage {
Data = blob
};
}
}
}
private async Task <int> SaveFast(IMediaAware media, MediaStorageItem item)
{
var sourceStream = item.SourceStream;
media.Size = (int)sourceStream.Length;
var streamParam = _db.DataProvider.CreateParameter("p0", sourceStream);
if (media.MediaStorageId == null)
{
// Insert new blob
var sql = "INSERT INTO MediaStorage (Data) Values(@p0)";
media.MediaStorageId = await _db.DataProvider.InsertIntoAsync(sql, streamParam);
}
else
{
// Update existing blob
var sql = "UPDATE MediaStorage SET Data = @p0 WHERE Id = @p1";
var idParam = _db.DataProvider.CreateParameter("p1", media.MediaStorageId.Value);
await _db.Database.ExecuteSqlRawAsync(sql, streamParam, idParam);
}
return(media.MediaStorageId.Value);
}
public override async Task SaveToAsync(Stream stream, IMediaAware media)
{
await _image.SaveAsync(stream);
media.Size = (int)stream.Length;
}
public abstract Task SaveToAsync(Stream stream, IMediaAware media);
