public async Task <ApiResponse <PutResult <Guid> > > Put([FromBody] BlobInputDto dto)
{
var key = await _blobService.Put(dto);
var result = new PutResult <Guid>(key);
return(ApiResponse.OK(result));
}
private BlobInputDto GetLargeBlob()
{
var dto = new BlobInputDto();
dto.TimeStamp = Mapper.Map <DateTime, long>(DateTime.UtcNow);
dto.Remark = "large blob";
var body = new byte[BlobEntity.BlobChunkSize * 8 + 100];
RandomUtils.GetRandomInstance().NextBytes(body);
dto.Body = Mapper.Map <byte[], string>(body);
return(dto);
}
public async Task <Guid> Put(BlobInputDto dto)
{
// 获取提交过来的内容, 计算校验值
var originalBytes = Mapper.Map <string, byte[]>(dto.Body);
if (dto.IsCompressed)
{
originalBytes = ArchiveUtils.DecompressFromGZip(originalBytes);
}
var hash = HashUtils.GetSHA256Hash(originalBytes);
using (var transaction = await _repository.BeginTransactionAsync())
{
// 如果有相同校验值的blob, 返回该blob
var existBlobId = await _repository.QueryNoTrackingAsync(q =>
q.Where(x => x.BodyHash == hash)
.Select(x => x.BlobId)
.FirstOrDefaultAsyncTestable());
if (existBlobId != Guid.Empty)
{
return(existBlobId);
}
}
// 对内容进行分块
var blobId = PrimaryKeyUtils.Generate <Guid>();
var chunks = SplitChunks(blobId, originalBytes, hash, dto.Remark, dto.TimeStamp);
// 添加新的blob
// 注意并发添加时可能会添加相同内容的blob
using (var transaction = await _repository.BeginTransactionAsync())
{
foreach (var chunk in chunks)
{
// 这里需要逐个分块提交, 否则会触发mysql的max_allowed_packet错误
await _repository.AddAsync(chunk);
await _repository.SaveChangesAsync();
}
transaction.Commit();
}
return(blobId);
}
public Task <long> Patch(Guid key, BlobInputDto dto)
{
return(Patch(x => x.BlobId == key, dto));
}
public Task <long> Patch(Expression <Func <BlobEntity, bool> > expression, BlobInputDto dto)
{
throw new NotSupportedException("modify an exist blob without changing it's blob id is dangerous and unsupported");
}