Bump docker image to Python 3.8

Author: vdboor

Dockerfile

@@ -1,6 +1,6 @@
 # Build environment has gcc and develop header files.
 # The installed files are copied to the smaller runtime container.
-FROM python:3.6-stretch as build-image
+FROM python:3.8-stretch as build-image
 ENV DEBIAN_FRONTEND=noninteractive \
     PYTHONUNBUFFERED=1 \
     PIP_NO_CACHE_DIR=off
@@ -12,8 +12,8 @@ ARG PIP_REQUIREMENTS=/app/src/requirements/docker.txt
 RUN pip install -r $PIP_REQUIREMENTS
 
 # Remove unneeded files
-RUN find /usr/local/lib/python3.6/site-packages/ -name '*.po' -delete && \
-    find /usr/local/lib/python3.6/site-packages/tinymce/ -regextype posix-egrep -not -regex '.*/langs/(en|nl).*\.js' -wholename '*/langs/*.js' -delete
+RUN find /usr/local/lib/python3.8/site-packages/ -name '*.po' -delete && \
+    find /usr/local/lib/python3.8/site-packages/tinymce/ -regextype posix-egrep -not -regex '.*/langs/(en|nl).*\.js' -wholename '*/langs/*.js' -delete
 
 # Node builder
 FROM node:16-buster as frontend-build
@@ -26,7 +26,7 @@ COPY src/frontend/ /app/src/frontend/
 RUN npm run gulp
 
 # Start runtime container
-FROM python:3.6-slim-stretch
+FROM python:3.8-slim-stretch
 ENV DEBIAN_FRONTEND=noninteractive \
     PYTHONUNBUFFERED=1 \
     PIP_NO_CACHE_DIR=off \
@@ -59,7 +59,7 @@ HEALTHCHECK --interval=5m --timeout=3s CMD curl -f http://localhost:8080/api/hea
 
 # Install dependencies
 COPY --from=build-image /usr/local/bin/ /usr/local/bin/
-COPY --from=build-image /usr/local/lib/python3.6/site-packages/ /usr/local/lib/python3.6/site-packages/
+COPY --from=build-image /usr/local/lib/python3.8/site-packages/ /usr/local/lib/python3.8/site-packages/
 COPY --from=frontend-build /app/src/frontend/static /app/src/frontend/static
 
 # Insert application code.

deployment/docker/uwsgi.ini

@@ -59,7 +59,7 @@ add-header = Connection: Keep-Alive
 # Static file serving with caching headers and gzip
 static-map = /static=/app/web/static
 static-map = /media=/app/web/media
-static-safe = /usr/local/lib/python2.7/site-packages/
+static-safe = /usr/local/lib/python3.8/site-packages/
 static-safe = /app/src/frontend/static/
 static-gzip-dir = /app/web/static/
 route-uri = ^/static/ addheader:Vary: Accept-Encoding