如何在Python中将PDF文档从Portrait转为Landscape

我需要用Python将PDF从纵向（Portrait）转为横向（Landscape），以下是我尝试的Django代码，但没得到预期结果，求解决方案。

def viewDocumentInvoice(request, slug):
    #fetch that invoice
    try:
        invoice = Invoice.objects.get(slug=slug)
        pass
    except:
        messages.error(request, 'Something went wrong')
        return redirect('invoices')

    #fetch all the products - related to this invoice
    products = Product.objects.filter(invoice=invoice)

    #Get Client Settings
    p_settings = Settings.objects.get(clientName='Kamrate Nigeria Limited')

    #Calculate the Invoice Total
    invoiceTotal = 0.0
    if len(products) > 0:
        for x in products:
            y = float(x.quantity) * float(x.price)
            invoiceTotal += y

    context = {}
    context['invoice'] = invoice
    context['products'] = products
    context['p_settings'] = p_settings
    context['invoiceTotal'] = "{:.2f}".format(invoiceTotal)
    # context['y'] = "{:.2f}".format(y)

    #The name of your PDF file
    filename = '{}.pdf'.format(invoice.uniqueId)  

    #HTML FIle to be converted to PDF - inside your Django directory
    template = get_template('invoice/pdf-template.html')

    #Render the HTML
    html = template.render(context)

    #Options - Very Important [Don't forget this]
    options = {
          'encoding': 'UTF-8',
          'javascript-delay':'10', #Optional
          'enable-local-file-access': None, #To be able to access CSS
          'page-size': 'A4',
          'custom-header' : [
              ('Accept-Encoding', 'gzip')
          ],
      }
      #Javascript delay is optional

    #Remember that location to wkhtmltopdf
    #config = pdfkit.configuration(wkhtmltopdf='/usr/bin/wkhtmltopdf')
    config = pdfkit.configuration(wkhtmltopdf='C:\Program Files\wkhtmltopdf/bin\wkhtmltopdf.exe')

    #IF you have CSS to add to template
    css1 = os.path.join(settings.CSS_LOCATION, 'assets', 'css', 'bootstrap.min.css')
    css2 = os.path.join(settings.CSS_LOCATION, 'assets', 'css', 'dashboard.css')

    #Create the file
    file_content = pdfkit.from_string(html, False, configuration=config, options=options)

    # pdf = PdfFileReader(file_content)
    # page = pdf.getPage(0).mediaBox
    # if page.getUpperRight_x() - page.getUpperLeft_x() > page.getUpperRight_y() - page.getLowerRight_y():
    #     print('Landscape')
    # else:
    #     print('Portrait')

    #Create the HTTP Response
    response = HttpResponse(file_content, content_type='application/pdf')
    response['Content-Disposition'] = 'inline; filename = {}'.format(filename)

    #Return
    return response

核心问题与解决方案 #

1. 问题根源

你的代码未在pdfkit的配置选项中指定页面方向，wkhtmltopdf默认生成纵向PDF，因此无法得到横向效果。

2. 具体修复步骤

（1）添加横向方向配置

在options字典中新增orientation参数，直接指定页面为横向：

options = {
      'encoding': 'UTF-8',
      'javascript-delay':'10',
      'enable-local-file-access': None,
      'page-size': 'A4',
      'orientation': 'Landscape',  # 关键：设置为横向
      'custom-header' : [
          ('Accept-Encoding', 'gzip')
      ],
}

（2）适配HTML模板布局

在你的PDF模板invoice/pdf-template.html中添加打印专用CSS，确保内容适配A4横向尺寸：

@media print {
    @page {
        size: A4 landscape;
        margin: 1cm;
    }
    body {
        width: 297mm; /* A4横向宽度 */
        height: 210mm; /* A4横向高度 */
        margin: 0 auto;
    }
}

3. 额外说明

• 无需事后读取PDF判断方向，生成阶段直接指定参数更高效，避免额外的PDF处理开销
• 确保wkhtmltopdf为最新版本，旧版本可能存在参数兼容性问题
• 若使用Bootstrap等框架，可调整栅格布局，利用横向页面的额外宽度优化内容排版

内容的提问来源于stack exchange，提问作者Oluwadamilare Alani