使用blobstore存储MIME类型

Question

如何也将传入blob的MIME类型存储到blobstore？我现在既不能获取使用处理程序blobstore_handlers.BlobstoreUploadHandler存储的名称，也不能获取存储的MIME类型。下面是我的不使用blobstore_handlers.BlobstoreUploadHandler的代码

    def create_image(number, self, file, ad):
        logging.debug('creating image')            
        try:
          file_name = files.blobstore.create()
          with files.open(file_name, 'a') as f:
              f.write(file)
          files.finalize(file_name)
          blob_key = files.blobstore.get_blob_key(file_name)
          logging.debug('creating image')
          img = Image(reference=ad) 
          logging.debug('creating image')
          img.primary_image = blob_key
          logging.debug('creating image')
          img.put()
          ad.put()
        except Exception:                
           self.response.write(Exception)

Answer 1

name和mime类型都可以作为参数传递到create：

def create(mime_type='application/octet-stream',
           _blobinfo_uploaded_filename=None):
  """Create a writable blobstore file.

  Args:
    mime_type: Resulting blob content MIME type as string.
    _blobinfo_uploaded_filename: Resulting blob's BlobInfo file name as string.

  Returns:
    A file name for blobstore file. This file can be opened for write
    by File API open function. To read the file or obtain its blob key, finalize
    it and call get_blob_key function.
  """