如何在Python中生成DOCX并将其保存在内存中？

我的任务是从模板生成DOCX文件,然后通过Flask提供该文件.我使用python-docx-templates,它只是python-docx的包装,允许使用jinja模板.

最后,他们建议使用StringIO仅将文件保存在内存中,因此我的代码如下所示：

def report_doc(user_id):
    # Prepare the data...

    from docxtpl import DocxTemplate

    doc = DocxTemplate(app.root_path+'/templates/report.docx')
    doc.render({
        # Pass parameters
    })
    from io import StringIO
    file_stream = StringIO()
    doc.save(file_stream)

    return send_file(file_stream, as_attachment=True, attachment_filename='report_'+user_id+'.docx')

保存时将引发错误TypeError：预期的字符串参数,为“ bytes”.谷歌搜索之后,我发现this answer表示ZipFile需要BytesIO.但是,当我用BytesIO代替StringIO时,它仅返回一个空文件,因此它不会引发任何错误,但绝对不会保存该文件.

在这种情况下究竟能做什么？如果这里有什么完全不对的地方,那么总体上该如何做？

谢谢！

UPD：这是对保存功能调用的完整跟踪的例外：

File "/ms/controllers.py", line 1306, in report_doc
    doc.save(file_stream)
  File "/.env/lib/python3.5/site-packages/docx/document.py", line 142, in save
    self._part.save(path_or_stream)
  File "/.env/lib/python3.5/site-packages/docx/parts/document.py", line 129, in save
    self.package.save(path_or_stream)
  File "/.env/lib/python3.5/site-packages/docx/opc/package.py", line 160, in save
    PackageWriter.write(pkg_file, self.rels, self.parts)
  File "/.env/lib/python3.5/site-packages/docx/opc/pkgwriter.py", line 33, in write
    PackageWriter._write_content_types_stream(phys_writer, parts)
  File "/.env/lib/python3.5/site-packages/docx/opc/pkgwriter.py", line 45, in _write_content_types_stream
    phys_writer.write(CONTENT_TYPES_URI, cti.blob)
  File "/.env/lib/python3.5/site-packages/docx/opc/phys_pkg.py", line 155, in write
    self._zipf.writestr(pack_uri.membername, blob)
  File "/usr/lib/python3.5/zipfile.py", line 1581, in writestr
    self.fp.write(zinfo.FileHeader(zip64))
TypeError: string argument expected, got 'bytes'

解决方法:

使用BytesIO实例是正确的,但是在将其传递到send_file之前需要rewind the file pointer：

Make sure that the file pointer is positioned at the start of data to
send before calling send_file().

所以这应该工作：

import io
from docxtpl import DocxTemplate

def report_doc(user_id):
   # Prepare the data...

   doc = DocxTemplate(app.root_path+'/templates/report.docx')
   doc.render({
        # Pass parameters
   })
   file_stream = io.BytesIO()
   doc.save(file_stream)
   file_stream.seek(0)

   return send_file(file_stream, as_attachment=True, attachment_filename='report_'+user_id+'.docx')

(在Firefox上进行测试,我发现浏览器即使指定了不同的文件名,也一直从缓存中检索文件,因此您可能需要在测试时清除浏览器的缓存,或者如果浏览器支持则禁用开发工具中的缓存,或者调整Flask cache control settings).

标签：python-docx,python
来源： https://codeday.me/bug/20191025/1930825.html