使用 ZipArchive、CsvHelper 和 Azure Blob 将流内压缩到 csv 给我留下一个空的存档 C#

Question

我正在尝试将已转换为 csv 的 sql 查询的压缩结果上传到 blob。

查看下面我的代码：

  //this doesn't work
  using (var sqlCommand = _dataPointService.OpenSqlConnectionForCsvQuery(device, start, end))
  using (var sqlDataReader = sqlCommand.ExecuteReader(CommandBehavior.CloseConnection))
  using (var blobWriteStream = appendBlobClient.OpenWrite(true))
  using (var zipArchive = new ZipArchive(blobWriteStream, ZipArchiveMode.Create))
  using (var streamWriter = new StreamWriter(zipArchive.CreateEntry(fileName + ".csv").Open()))
  using (var csvWriter = new CsvWriter(streamWriter, new CsvConfiguration(CultureInfo.InvariantCulture)))
  { 
    var generator = new StreamCsvGenerator(device, start, end, showTemperatureInFahrenheit);

    generator.FeedHeader(csvWriter);

    {
      while (sqlDataReader.Read())
      {
        generator.FeedRow(csvWriter, sqlDataReader);
      }
    }

    streamWriter.Flush();
  }

我最终在我的 blob 中得到以下空存档：

但是，如果我不费心压缩，一切都会好起来的：

 //this works
  using (var sqlCommand = _dataPointService.OpenSqlConnectionForCsvQuery(device, start, end))
  using (var sqlDataReader = sqlCommand.ExecuteReader(CommandBehavior.CloseConnection))
  using (var blobWriteStream = appendBlobClient.OpenWrite(true))
  using (var streamWriter = new StreamWriter(blobWriteStream))
  using (var csvWriter = new CsvWriter(streamWriter, new CsvConfiguration(CultureInfo.InvariantCulture)))
  {
    var generator = new StreamCsvGenerator(device, start, end, showTemperatureInFahrenheit);

    generator.FeedHeader(csvWriter);

    {
      while (sqlDataReader.Read())
      {
        generator.FeedRow(csvWriter, sqlDataReader);
      }
    }

    streamWriter.Flush();
  }

结果如下：

我是否错误地使用了 ZipArchive / ZipEntry 流？我该如何解决？

Answer 1

我相信你需要告诉 ZipArchive 保持 Stream 打开，这样你就可以用 CsvHelper

写入它

 using (var zipArchive = new ZipArchive(blobWriteStream, ZipArchiveMode.Create, true))

如果这不起作用，您可以先写入 MemoryStream，然后使用 appendBlobClient 上传。第一部分有效，我能够写入计算机上的本地文件。我无法测试 appendBlobClient 部分，因为我没有设置 Azure 帐户。

using (var memoryStream = new MemoryStream())
{
    using (var sqlCommand = _dataPointService.OpenSqlConnectionForCsvQuery(device, start, end))
    using (var sqlDataReader = sqlCommand.ExecuteReader(CommandBehavior.CloseConnection))
    using (var zipArchive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
    using (var streamWriter = new StreamWriter(zipArchive.CreateEntry(fileName + ".csv").Open()))
    using (var csvWriter = new CsvWriter(streamWriter, new CsvConfiguration(CultureInfo.InvariantCulture)))
    {
        var generator = new StreamCsvGenerator(device, start, end, showTemperatureInFahrenheit);

        generator.FeedHeader(csvWriter);

        {
            while (sqlDataReader.Read())
            {
                generator.FeedRow(csvWriter, sqlDataReader);
            }
        }

        streamWriter.Flush();
    }
    
    using (var blobWriteStream = appendBlobClient.OpenWrite(true))
    {
        memoryStream.Seek(0, SeekOrigin.Begin);
        
        blobWriteStream.AppendBlock(memoryStream, memoryStream.Length);
    }
}

Answer 2

修复是将我的 Azure.Storage.Blobs 包更新到最新版本。

我使用的是 12.6.0 版本。更新到 12.8.3 后，一切正常。

以下是我的呼叫如何寻找将来遇到此问题的人：

      var appendBlobClient = BlobStorage.CreateAppendBlobClient(blobName);
      
      using (var sqlCommand = _dataPointService.OpenSqlConnectionForCsvQuery(device, start, end))
      using (var sqlDataReader = sqlCommand.ExecuteReader(CommandBehavior.CloseConnection))
      using (var blobWriteStream = appendBlobClient.OpenWrite(true))
      using (var zipArchive = new ZipArchive(blobWriteStream, ZipArchiveMode.Create))
      using (var zipEntryStream = zipArchive.CreateEntry(fileName + ".csv").Open())
      using (var streamWriter = new StreamWriter(zipEntryStream))
      using (var csvWriter = new CsvWriter(streamWriter, new CsvConfiguration(CultureInfo.CurrentCulture)))
      {
        // this class is a csvWriter helper
        var generator = new StreamCsvGenerator(device, start, end, showTemperatureInFahrenheit);

        generator.FeedHeader(csvWriter); // this writes some comments at the top of the csv file
        
        while (sqlDataReader.Read())
        {
          generator.FeedRow(csvWriter, sqlDataReader); // this writes records
        }
      }

使用 ZipArchive、CsvHelper 和 Azure Blob 将流内压缩到 csv 给我留下一个空的存档 C#

zipping in-stream to a csv using ZipArchive, CsvHelper, and Azure Blobs leaves me with an empty archive C#

c#

zip

stream

csvhelper

azure-blob-storage