Weasyprint Dockerfile for GAE - google-app-engine

Question

I am trying to install weasyprint on gae, i know we can install external libraries by passing it in a Dockerfile by changing the runtime from python to custom in app.yaml. I am having trouble creating the Dockerfile for weasyprint libraries.

Answer 1

Here is a simple example that I wrote following these instructions. I have tested it and the deployment on GAE has been successful for me:
Dockerfile
FROM gcr.io/google-appengine/python
# Create a virtualenv for dependencies. This isolates these packages from
# system-level packages.
# Use -p python3 or -p python3.7 to select python version. Default is version 2.
RUN virtualenv /env -p python3.7
# Setting these environment variables are the same as running
# source /env/bin/activate.
ENV VIRTUAL_ENV /env
ENV PATH /env/bin:$PATH
# Install platform's packages required for WeasyPrint
RUN apt-get update && apt-get -y install build-essential python3-dev python3-pip \
python3-setuptools python3-wheel python3-cffi \
libcairo2 libpango-1.0-0 libpangocairo-1.0-0 libgdk-pixbuf2.0-0 libffi-dev shared-mime-info
# Copy the application's requirements.txt and run pip to install all
# dependencies into the virtualenv.
ADD requirements.txt requirements.txt
RUN pip install -r requirements.txt
# Add the application source code.
ADD . /app
# Run a WSGI server to serve the application. gunicorn must be declared as
# a dependency in requirements.txt.
CMD gunicorn -b :$PORT main:app
app.yaml
runtime: custom
env: flex
rquirements.txt
gunicorn==19.1.1
Flask==1.0.2
WeasyPrint>=0.34
main.py
from flask import Flask
from weasyprint import *
app = Flask(__name__)
#app.route('/')
def hello():
return 'Success!'
if __name__ == '__main__':
app.run(host='127.0.0.1', port=8080)
Note that as WeasyPrint documentation mentions, platform's packages (such as cairo, Pango and GDK-PixBuf) must be installed separately. They are installed with the following command I added in the Dockerfile:
RUN apt-get update && apt-get -y 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