修复 Django 项目中 xhtm2pdf 的类型错误答案

【问题标题】：Fixing a type error for xhtm2pdf in a Django Project修复 Django 项目中 xhtm2pdf 的类型错误
【发布时间】：2021-10-16 08:08:37
【问题描述】：

我正在尝试为我的 Django 项目生成 PDF。我用过pip install xhtml2pdf

PDF 是用纯文本生成的，但是当我在 pdf.html 中添加样式时，我得到了这个Exception Type: TypeError：

'<' not supported between instances of 'int' and 'NoneType'

这里是views.py：

def admin_order_pdf(request,info_id):
    info = get_object_or_404(Info, id=info_id)
    template_path = 'businessplan/pdf.html'
    context = {'info': info}
    # Create a Django response object, and specify content_type as pdf
    response = HttpResponse(content_type='application/pdf')
    # response['Content-Disposition'] = 'attachment; filename="report.pdf"'
    response['Content-Disposition'] = 'filename="order_{}.pdf"'.format(Info.id)
    # find the template and render it.
    template = get_template(template_path)
    html = template.render(context)

    # create a pdf
    pisa_status = pisa.CreatePDF(html, dest=response)
    # if error then show some funy view
    if pisa_status.err:
       return HttpResponse('We had some errors <pre>' + html + '</pre>')
    return response

这里是pdf.html

{% load static %}

<html>
  <head>
    <meta charset="utf-8">
    <link rel="stylesheet" href="{% static 'css/report.css' %}" />
<!--    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC" crossorigin="anonymous">-->

    <title>{{ info.businessName }}</title>
    <style>

    @charset "UTF-8";
    @font-face {
      font-family: Fira Sans;
      font-weight: 400;
      src: url('/static/img/FiraSans-Regular.otf'); }

    @font-face {
      font-family: Fira Sans;
      font-style: italic;
      font-weight: 400;
      src: url('/static/img/FiraSans-Italic.otf'); }

    @font-face {
      font-family: Fira Sans;
      font-weight: 300;
      src: url('/static/img/FiraSans-Light.otf'); }

    @font-face {
      font-family: Fira Sans;
      font-style: italic;
      font-weight: 300;
      src: url('/static/img/FiraSans-LightItalic.otf'); }

    @font-face {
      font-family: Fira Sans;
      font-weight: bold;
      src: url('/static/img/FiraSans-Bold.otf'); }

    @page {
      @top-left {
        background: #fbc847;
        content: counter(page);
        height: 1cm;
        text-align: center;
        width: 1cm; }

--------------long lines of similar code css----------
      html body article#competences section {
        padding: .5cm 0; }
        html body article#competences section#table-content::before {
          background: url('/static/img/table-content.svg') no-repeat center #fbc847;
          background-size: 50%;
          content: '';
          display: inline-block;
          float: left;
          height: 2cm;
          margin-right: .5cm;
          vertical-align: middle;
          width: 2cm; }
.................. long lines of similar css 
    </style>
    <meta name="description" content="Report example">
  </head>

  <body>
    <article id="cover">
      <h1>{{ info.businessName }}<br>
      <small>Business Plan <br>
         Created on: {{ info.date_posted }}
      </small>
      </h1>
      <address>
        {{ info.businessName }}
        {{ info.businessAddress }}
      </address>

我正在寻找类似问题的答案，但我不知道从哪里开始修复。

我知道该错误与 pdf.html 中的 CSS 代码有关，但我不知道为什么会显示。当我删除 pdf 以纯文本显示的样式时。

这是回溯：

Traceback (most recent call last):
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\django\core\handlers\exception.py", line 47, in inner
    response = get_response(request)
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\django\core\handlers\base.py", line 181, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "C:\Users\User\Desktop\consultation\businessplan\views.py", line 49, in admin_order_pdf
    pisa_status = pisa.CreatePDF(html, dest=response)
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\xhtml2pdf\document.py", line 104, in pisaDocument
    context = pisaStory(src, path, link_callback, debug, default_css, xhtml,
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\xhtml2pdf\document.py", line 67, in pisaStory
    pisaParser(src, context, default_css, xhtml, encoding, xml_output)
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\xhtml2pdf\parser.py", line 755, in pisaParser
    context.parseCSS()
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\xhtml2pdf\context.py", line 469, in parseCSS
    self.css = self.cssParser.parse(self.cssText)
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\xhtml2pdf\w3c\cssParser.py", line 454, in parse
    src, stylesheet = self._parseStylesheet(src)
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\xhtml2pdf\w3c\cssParser.py", line 556, in _parseStylesheet
    src, atResults = self._parseAtKeyword(src)
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\xhtml2pdf\w3c\cssParser.py", line 685, in _parseAtKeyword
    src, result = self._parseAtIdent(src)
  File "C:\Users\User\Desktop\consultation\venv\lib\site-packages\xhtml2pdf\w3c\cssParser.py", line 875, in _parseAtIdent
    if semiIdx is not None and semiIdx < blockIdx:
TypeError: '<' not supported between instances of 'int' and 'NoneType'

我不确定css是否是视图导致错误的原因

我的问题：

这个错误的原因是什么，我该如何解决？

谢谢

【问题讨论】：

你能显示整个堆栈跟踪吗？
@bdbd 我已经用回溯更新了帖子，谢谢
尝试remove .format(Info.id)
@PrOgRaMmEr 同样的错误显示
尝试将您的 css 导出到外部文件。可能是您的 css 有一些难以解析的 xml 字符。您还可以使用 CDATA 部分

标签： python css python-3.x django xhtml2pdf

【解决方案1】：

删除@charset "UTF-8";

【讨论】：

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