WeasyPrint: CAIRO_STATUS_TAG_ERROR: b'invalid tag name, attributes, or nesting'

Hello,

I encountered a strange error. When I try to render a pdf in my flask app with the following code:

@some_blueprint.route("/print/<string:file_hash>")
def print_pdf(file_hash):
    html = HTML(string="<html><head><title>Test</title></head><body><h1>test</h1></body></html>")
    return render_pdf(html)

Then I get:

Traceback (most recent call last):
  File "/usr/local/lib/python3.6/dist-packages/flask/app.py", line 2309, in __call__
    return self.wsgi_app(environ, start_response)
  File "/usr/local/lib/python3.6/dist-packages/flask/app.py", line 2295, in wsgi_app
    response = self.handle_exception(e)
  File "/usr/local/lib/python3.6/dist-packages/flask/app.py", line 1741, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python3.6/dist-packages/flask/_compat.py", line 35, in reraise
    raise value
  File "/usr/local/lib/python3.6/dist-packages/flask/app.py", line 2292, in wsgi_app
    response = self.full_dispatch_request()
  File "/usr/local/lib/python3.6/dist-packages/flask/app.py", line 1815, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/usr/local/lib/python3.6/dist-packages/flask/app.py", line 1718, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python3.6/dist-packages/flask/_compat.py", line 35, in reraise
    raise value
  File "/usr/local/lib/python3.6/dist-packages/flask/app.py", line 1813, in full_dispatch_request
    rv = self.dispatch_request()
  File "/usr/local/lib/python3.6/dist-packages/flask/app.py", line 1799, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/azk/azk/controllers/hiwi.py", line 184, in print_pdf
    return render_pdf(html)
  File "/usr/local/lib/python3.6/dist-packages/flask_weasyprint/__init__.py", line 209, in render_pdf
    pdf = html.write_pdf(stylesheets=stylesheets)
  File "/usr/local/lib/python3.6/dist-packages/weasyprint/__init__.py", line 199, in write_pdf
    target, zoom, attachments)
  File "/usr/local/lib/python3.6/dist-packages/weasyprint/document.py", line 613, in write_pdf
    levels.pop(), title, link_attribs, 0)
  File "/usr/local/lib/python3.6/dist-packages/cairocffi/surfaces.py", line 903, in add_outline
    self._check_status()
  File "/usr/local/lib/python3.6/dist-packages/cairocffi/surfaces.py", line 160, in _check_status
    _check_status(cairo.cairo_surface_status(self._pointer))
  File "/usr/local/lib/python3.6/dist-packages/cairocffi/__init__.py", line 79, in _check_status
    raise exception(message, status)
cairocffi.CairoError: cairo returned CAIRO_STATUS_TAG_ERROR: b'invalid tag name, attributes, or nesting'

Actually I am using flask_weasyprint, but the error is the same when using weasyprint directly. So far I have not been able to reproduce this with a simple flask application, but after removing the <h1> and </h1> tag everythings fine.

My python env consists of:

alembic==1.0.2
asn1crypto==0.24.0
bcrypt==3.1.4
blinker==1.4
bokeh==1.0.1
cairocffi==0.9.0
CairoSVG==2.2.1
certifi==2018.10.15
cffi==1.11.5
chardet==3.0.4
Click==7.0
coverage==4.5.1
cryptography==2.1.4
cssselect2==0.2.1
decorator==4.3.0
defusedxml==0.5.0
Flask==1.0.2
Flask-Bcrypt==0.7.1
Flask-DebugToolbar==0.10.1
Flask-Login==0.4.1
Flask-Migrate==2.3.0
flask-mongoengine==0.9.5
Flask-Principal==0.4.0
Flask-SQLAlchemy==2.3.2
Flask-WeasyPrint==0.5
Flask-WTF==0.14.2
html5lib==1.0.1
idna==2.6
infinity==1.4
intervals==0.8.1
itsdangerous==1.1.0
Jinja2==2.10
keyring==10.6.0
keyrings.alt==3.0
ldap==1.0.2
ldap3==2.5.1
Mako==1.0.7
MarkupSafe==1.1.0
mongoengine==0.16.0
numpy==1.15.4
packaging==18.0
pandas==0.23.4
Pillow==5.3.0
ply==3.11
pyasn1==0.4.4
pyasn1-modules==0.2.2
pycparser==2.18
pycrypto==2.6.1
pygobject==3.26.1
pymongo==3.7.2
PyMySQL==0.9.2
pyparsing==2.3.0
Pyphen==0.9.5
python-dateutil==2.7.5
python-editor==1.0.3
python-ldap==3.1.0
pytz==2018.7
pyxdg==0.25
PyYAML==3.13
regex==2018.11.7
requests==2.20.0
SecretStorage==2.3.1
six==1.11.0
SQLAlchemy==1.2.12
SQLAlchemy-Utils==0.33.6
tinycss2==0.6.1
tornado==5.1.1
urllib3==1.24.1
validators==0.12.2
WeasyPrint==43
webencodings==0.5.1
Werkzeug==0.14.1
WTForms==2.2.1
WTForms-Alchemy==0.16.7
WTForms-Components==0.10.3

and the whole app is running in a docker container which is based on ubuntu 18.04. Is there anything I am doing wrong?

About this issue

Original URL
State: closed
Created 6 years ago
Comments: 44 (39 by maintainers)

Commits related to this issue

Localize floats used by Cairo tags According to the documentation (and to the code), Cairo seems to rely on locale-dependent strings for tag attributes. It's for sure a bad idea, but at least try to ... — committed to Kozea/WeasyPrint by liZe 6 years ago
Use font_map_set_default instead of set_font_map Related to #742. — committed to Kozea/WeasyPrint by liZe 6 years ago
Don't localize numbers on Windows Related to #742. — committed to Kozea/WeasyPrint by liZe 6 years ago

Most upvoted comments

Do-it-ourselves or use the sledgehammer seems to be the choice.

Or…

As Adrian says (and I think he’s right), %f doesn’t insert thousands separators. As the only problem we have is the decimal separators (right?), we can just remove the decimal part. The greatest error we can have is 0.5pt (0.18mm), maybe that’s an error we can live with.

liZe on Dec 29, 2018

I’ll open an issue on Cairo’s bug tracker.

https://gitlab.freedesktop.org/cairo/cairo/issues/347

liZe on Nov 22, 2018