refactor(dockerfile): simplify the image definition

Improve cachability by reordering COPY directives and removing
unnecessary RUN directive.

Remove unnecessary user switches.

Remove workaround for missing user home directory.

Reduce the size of the build context.

Author: niheconomoum

.dockerignore

@@ -0,0 +1,2 @@
+.*
+*.md

Dockerfile

@@ -1,21 +1,13 @@
-FROM satosa AS custom_code
-# workaround https://github.com/IdentityPython/satosa-docker/issues/6
-USER root
-RUN mkdir -p /home/satosa; chown satosa:satosa /home/satosa
-USER satosa
 # build custom micro services
+FROM satosa AS custom_code
 COPY --chown=satosa:satosa src /home/satosa/src
 RUN cd /home/satosa/src/static_content; pip install --user .
 
 FROM satosa
-USER root
-RUN pip install --no-cache-dir satosa[ldap]==${SATOSA_VERSION}
-COPY --chown=satosa:satosa *.yaml /etc/satosa/
-COPY --chown=satosa:satosa plugins /etc/satosa/plugins
-RUN mkdir -p /home/satosa; chown satosa:satosa /home/satosa
+COPY *.yaml /etc/satosa/
+COPY plugins /etc/satosa/plugins
 COPY --from=custom_code /home/satosa/.local /home/satosa/.local
-COPY delayed-entrypoint.sh /usr/local/bin/
-USER satosa:satosa
+COPY --chown=root:root delayed-entrypoint.sh /usr/local/bin/
 ENV STARTUP_DELAY=300
 ENTRYPOINT ["delayed-entrypoint.sh"]
 CMD ["gunicorn","-b0.0.0.0:8080","satosa.wsgi:app"]