I'm using WeasyPrint 52.3 (latest version available at time of writing) along with Django 2.2 LTS on Python 3.6 on a Windows 10 development machine; all is working fine.
However when I try to render a PDF on my Linux machine (same WeasyPrint/Django/Python versions), all items I try to load from an URI are not shown, including images and CSS. When not using WeasyPrint, images/CSS are properly loaded. My images/CSS are available at https://myhost.tld/some.css and myhost has its certs signed.
When using inline CSS, the CSS is rendered fine.
I've tried to enable WeasyPrint logging through:
import logging
logger = logging.getLogger('weasyprint')
logger.addHandler(logging.FileHandler('/tmp/weasyprint.log'))
and I see following output:
Failed to load stylesheet at https://myhost.tld/assets/css/pdf.css : URLError: <urlopen error [Errno -3] Temporary failure in name resolution>
How can this be? My DNS system is properly set up for myhost.tld.
Ensure myhost.tld is part of the /etc/hosts file:
127.0.0.1 localhost
127.0.1.1 myhost
127.0.2.1 myhost.tld
Restart the right services and the files will load.