[Django]-Dlopen() failed to load a library: cairo / cairo-2

This was solved for me by installing the following dependencies on Ubuntu:

 sudo apt-get install libpango1.0-0
 sudo apt-get install libcairo2
 sudo apt-get install libpq-dev

Check out the dependencies at the link:

http://weasyprint.readthedocs.io/en/latest/install.html

I also had the same issue on a fresh installation of weasyprint on OSX EL CAPITAN.
This is how I solved it.

Firstly, cairo was not found by when installed via pip, so I tried installing it via homebrew using the following command

brew install cairo pango gdk-pixbuf libxml2 libxslt libffi

Once this is done, I tried to find out the path of cairo installation. For my case, the location was /usr/local/homebrew/Cellar/cairo/1.14.6_1/lib/ I just exported this to my DYLD library path

export DYLD_LIBRARY_PATH=/usr/local/homebrew/Cellar/cairo/1.14.6_1/lib/

Then I uninstalled and installed weasyprint again

pip uninstall weasyprint
pip install weasyprint

Post that, I tried to run weasyprint, but got a new error

Traceback (most recent call last):
File "/Users/anurag/VirtualEnvs/test/bin/weasyprint", line 11, in <module>
 load_entry_point('WeasyPrint==0.31', 'console_scripts', 'weasyprint')()
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/pkg_resources/__init__.py", line 565, in load_entry_point
 return get_distribution(dist).load_entry_point(group, name)
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/pkg_resources/__init__.py", line 2598, in load_entry_point
 return ep.load()
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/pkg_resources/__init__.py", line 2258, in load
 return self.resolve()
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/pkg_resources/__init__.py", line 2264, in resolve
 module = __import__(self.module_name, fromlist=['__name__'], level=0)
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/weasyprint/__init__.py", line 338, in <module>
 from .css import PARSER, preprocess_stylesheet  # noqa
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/weasyprint/css/__init__.py", line 30, in <module>
 from . import computed_values
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/weasyprint/css/computed_values.py", line 18, in <module>
 from .. import text
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/weasyprint/text.py", line 216, in <module>
 'libgobject-2.0.dylib')
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/weasyprint/text.py", line 212, in dlopen
 return ffi.dlopen(names[0])  # pragma: no cover
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/cffi/api.py", line 139, in dlopen
 lib, function_cache = _make_ffi_library(self, name, flags)
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/cffi/api.py", line 770, in _make_ffi_library
 backendlib = _load_backend_lib(backend, libname, flags)
File "/Users/anurag/VirtualEnvs/test/lib/python2.7/site-packages/cffi/api.py", line 759, in _load_backend_lib
 return backend.load_library(name, flags)
OSError: cannot load library gobject-2.0: dlopen(gobject-2.0, 2): image not found

I tried to find out the location of object library. Found it in /opt/local/lib and set the fallback library path

export DYLD_FALLBACK_LIBRARY_PATH=/opt/local/lib

After that, I tried running weasyprint again, and it worked

(test)anurag-mac:~ anurag$ weasyprint --version
WeasyPrint version 0.31

I hope someone else also finds it useful.

UPDATE-1

Although the above method worked, MySQL python started giving errors because of this and culprit was defining a fallback library path. So I removed this line

export DYLD_FALLBACK_LIBRARY_PATH=/opt/local/lib

which gave me the gobject error again, then I tried finding the location of its installation and appended to the DYLD_LIBRARY_PATH

export DYLD_LIBRARY_PATH=/usr/local/homebrew/Cellar/cairo/1.14.6_1/lib/:/usr/local/homebrew/Cellar/glib/2.48.2/lib/

After doing that, I got a similar error for pango. After correcting all the errors, this is the final library path which worked

export DYLD_LIBRARY_PATH=/usr/local/homebrew/Cellar/cairo/1.14.6_1/lib/:/usr/local/homebrew/Cellar/glib/2.48.2/lib/:/usr/local/homebrew/Cellar/pango/1.40.3/lib/

I had the same error with boxes.py on macOS Mojave. My solution was to install cairocffi with pip3 and cairo with brew. The two commands fail on their own, but together they work for boxes.py:

pip3 install cairocffi
brew install cairo

If you are getting this error when using weasyprint, then you may have forgotten to install Pango, GdkPixbuf, and cairo dependencies of weasyprint which cannot be installed using pip/pip3

For Debain/Ubuntu

sudo apt-get install build-essential python3-dev python3-pip python3-setuptools python3-wheel python3-cffi libcairo2 libpango-1.0-0 libpangocairo-1.0-0 libgdk-pixbuf2.0-0 libffi-dev shared-mime-info

For other platforms refer the below link

https://weasyprint.readthedocs.io/en/latest/install.html

I solve this problem by following this link:
https://github.com/Kozea/WeasyPrint/issues/79

sudo apt-get install build-essential python3-dev python3-pip python3-setuptools python3-wheel python3-cffi libcairo2 libpango-1.0-0 libpangocairo-1.0-0 libgdk-pixbuf2.0-0 libffi-dev shared-mime-info

http://weasyprint.readthedocs.io/en/latest/install.html#linux