AttributeError：“ NoneType”对象没有属性“ app”

Question

下面的代码给出了错误：

Traceback (most recent call last):
  File "pdf.py", line 14, in <module>
    create_pdf(render_template('templates.htm'))
  File "/usr/local/lib/python2.7/dist-packages/flask/templating.py", line 123, in render_template
    ctx.app.update_template_context(context)
AttributeError: 'NoneType' object has no attribute 'app'

码：

from xhtml2pdf import pisa
from StringIO import StringIO
from flask import render_template,Flask

app=Flask(__name__)
app.debug=True

@app.route("/")
def create_pdf(pdf_data):
        filename= "file.pdf"
        pdf=pisa.CreatePDF( StringIO(pdf_data),file(filename, "wb"))

if __name__ == "__main__":
        create_pdf(render_template('templates.htm'))

Answer 1

从代码中，我可以看到你希望允许用户下载pdf。

from xhtml2pdf import pisa
from StringIO import StringIO
from flask import render_template,Flask, Response

app=Flask(__name__)
app.debug=True

@app.route("/")
def create_pdf(pdf_data):
        filename= "file.pdf"
        pdf=pisa.CreatePDF( StringIO(pdf_data),file(filename, "wb"))
        return Response(pdf, mimetype='application/octet-stream',
                        headers={"Content-Disposition": "attachment;filename=%s" % filename})

if __name__ == "__main__":
        app.run()

现在开始 python aboveprogram.py

去 http://localhost:5000