cannot load library 'pango-1.0-0': pango-1.0-0 issue

I got this error suddenly and not sure why, it was working perfectly earlier I was using django-weasyprint previously I removed it and used weasyprint then on my Dockerfile I added this.

# Install apt packages
RUN apt-get update && apt-get install --no-install-recommends -y \
  # dependencies for building Python packages
  build-essential \
  # psycopg2 dependencies
  libpq-dev \
  # WeasyPrint dependencies
  libpango-1.0-0 \
  libharfbuzz0b \
  libpangoft2-1.0-0

Previous I have this on my Dockerfile

  # WeasyPrint dependencies
  libcairo2 \
  libpango-1.0-0 \
  libpangocairo-1.0-0 \
  libgdk-pixbuf2.0-0 \
  libffi-dev \
  shared-mime-info

Error from the console

water_conservation_docs | Traceback (most recent call last):
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/sphinx/config.py", line 327, in eval_config_file
water_conservation_docs |     execfile_(filename, namespace)
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/sphinx/util/pycompat.py", line 88, in execfile_
water_conservation_docs |     exec(code, _globals)
water_conservation_docs |   File "/docs/conf.py", line 27, in <module>
water_conservation_docs |     django.setup()
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/django/__init__.py", line 24, in setup
water_conservation_docs |     apps.populate(settings.INSTALLED_APPS)
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/django/apps/registry.py", line 122, in populate
water_conservation_docs |     app_config.ready()
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/django/contrib/admin/apps.py", line 24, in ready
water_conservation_docs |     self.module.autodiscover()
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/django/contrib/admin/__init__.py", line 24, in autodiscover
water_conservation_docs |     autodiscover_modules('admin', register_to=site)
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/django/utils/module_loading.py", line 47, in autodiscover_modules
water_conservation_docs |     import_module('%s.%s' % (app_config.name, module_to_search))
water_conservation_docs |   File "/usr/local/lib/python3.8/importlib/__init__.py", line 127, in import_module
water_conservation_docs |     return _bootstrap._gcd_import(name[level:], package, level)
water_conservation_docs |   File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
water_conservation_docs |   File "<frozen importlib._bootstrap>", line 991, in _find_and_load
water_conservation_docs |   File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
water_conservation_docs |   File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
water_conservation_docs |   File "<frozen importlib._bootstrap_external>", line 848, in exec_module
water_conservation_docs |   File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
water_conservation_docs |   File "/app/water_conservation_api/core/admin.py", line 16, in <module>
water_conservation_docs |     from water_conservation_api.core.services import OrganizationService
water_conservation_docs |   File "/app/water_conservation_api/core/services.py", line 27, in <module>
water_conservation_docs |     from water_conservation_api.core.tasks import (
water_conservation_docs |   File "/app/water_conservation_api/core/tasks.py", line 17, in <module>
water_conservation_docs |     from water_conservation_api.utils.helpers import generate_pdf, send_job_notification
water_conservation_docs |   File "/app/water_conservation_api/utils/helpers.py", line 9, in <module>
water_conservation_docs |     from weasyprint import HTML
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/weasyprint/__init__.py", line 322, in <module>
water_conservation_docs |     from .css import preprocess_stylesheet  # noqa isort:skip
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/weasyprint/css/__init__.py", line 27, in <module>
water_conservation_docs |     from . import computed_values, counters, media_queries
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/weasyprint/css/computed_values.py", line 16, in <module>
water_conservation_docs |     from ..text.ffi import ffi, pango, units_to_double
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/weasyprint/text/ffi.py", line 383, in <module>
water_conservation_docs |     pango = _dlopen(
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/weasyprint/text/ffi.py", line 377, in _dlopen
water_conservation_docs |     return ffi.dlopen(names[0])  # pragma: no cover
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/cffi/api.py", line 150, in dlopen
water_conservation_docs |     lib, function_cache = _make_ffi_library(self, name, flags)
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/cffi/api.py", line 832, in _make_ffi_library
water_conservation_docs |     backendlib = _load_backend_lib(backend, libname, flags)
water_conservation_docs |   File "/usr/local/lib/python3.8/site-packages/cffi/api.py", line 827, in _load_backend_lib
water_conservation_docs |     raise OSError(msg)
water_conservation_docs | OSError: cannot load library 'pango-1.0-0': pango-1.0-0: cannot open shared object file: No such file or directory.  Additionally, ctypes.util.find_library() did not manage to locate a library called 'pango-1.0-0'

[aabanaag]

Thank you for pointing it to a better path. I’ll close this one since this is not really an issue for WeasyPrint

[liZe]

As explained earlier, this error is probably caused by environment variables removed or modified by cookiecutter, or Sphinx, or Django. Your Docker instance works when you call WeasyPrint, but it doesn’t when you use these tools, so…

You can try to use WeasyPrint with only Django, and see if it works. You can then try with Sphinx, and then with cookiecutter until you get the error. When you know which tool changes the environment variables, it will be easier to find a solution.