python - model.save 上的 Django Filefield UnicodeDecodeError

Question

StackOverflow 上的类似问题好像都没有跟我一样的问题，我只找到了http://qnundrum.com/question/766895 ，从未得到答复。我正在运行 Python 3.3 和 Django 1.6，所以通常会自动处理 Unicode 内容。感谢我能得到的任何帮助。

我正在尝试将自动生成的电子书保存到我的数据库中以供以后检索。有些书包含非 ASCII 字符。我已经完成了这一代，.mobi 和 .epub 的工作符合预期。这是 models.py:

class StoryDownload(models.Model):
    text = models.OneToOneField('stories.Story', primary_key=True, related_name='downloads')
    epub = models.FileField(upload_to='epub/', blank=True, null=True)
    mobi = models.FileField(upload_to='mobi/', blank=True, null=True)

    def update_downloads(self):
        #code to generate epub and mobi files from text
        ...
        self.epub = File(open('filename.epub'), 'r'))
        self.mobi = File(open('filename.mobi'), 'r'))
        self.save()
        ...

self.save() 出现的错误让我很困惑；如果文件被接受为 Django File 对象，那么为什么我不能保存它们？

回溯:

File "C:\Users\Chris\Envs\stories\lib\site-packages\django\core\handlers\base.py" in get_response
  114.                     response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\views\generic\base.py" in view
  69.             return self.dispatch(request, *args, **kwargs)
File "C:\Users\Chris\Envs\stories\lib\site-packages\braces\views\_access.py" in dispatch
  64.             request, *args, **kwargs)
File "C:\Users\Chris\Envs\stories\lib\site-packages\guardian\mixins.py" in dispatch
  190.             **kwargs)
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\views\generic\base.py" in dispatch
  87.         return handler(request, *args, **kwargs)
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\views\generic\edit.py" in post
  228.         return super(BaseUpdateView, self).post(request, *args, **kwargs)
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\views\generic\edit.py" in post
  171.             return self.form_valid(form)
File "C:\Users\Chris\Envs\stories\dev\akrito\chapters\views.py" in form_valid
  69.         self.chapter.story.save()
File "C:\Users\Chris\Envs\stories\dev\akrito\stories\models.py" in save
  87.             self.downloads.update_downloads()
File "C:\Users\Chris\Envs\stories\dev\akrito\stories\models.py" in update_downloads
  135.         self.save()
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\db\models\base.py" in save
  545.                        force_update=force_update, update_fields=update_fields)
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\db\models\base.py" in save_base
  573.             updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\db\models\base.py" in _save_table
  632.                       for f in non_pks]
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\db\models\base.py" in <listcomp>
  632.                       for f in non_pks]
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\db\models\fields\files.py" in pre_save
  252.             file.save(file.name, file, save=False)
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\db\models\fields\files.py" in save
  86.         self.name = self.storage.save(name, content)
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\core\files\storage.py" in save
  49.         name = self._save(name, content)
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\core\files\storage.py" in _save
  203.                         for chunk in content.chunks():
File "C:\Users\Chris\Envs\stories\lib\site-packages\django\core\files\base.py" in chunks
  76.             data = self.read(chunk_size)
File "C:\Users\Chris\Envs\stories\lib\encodings\cp1252.py" in decode
  23.         return codecs.charmap_decode(input,self.errors,decoding_table)[0]

Exception Type: UnicodeDecodeError at /stories/2/1/e/
Exception Value: 'charmap' codec can't decode byte 0x81 in position 123: character maps to <undefined>

Answer 1

对于文本文件，您需要使用所需的编码 调用open。默认编码是 locale.getpreferredencoding(False)，这就是回溯显示它尝试使用 Windows 1252 代码页进行解码的原因。

也就是说，MOBI 和 EPUB 文件是压缩文件，应该以二进制模式打开，例如打开('filename.epub', 'rb')。