singleuser: Allow user installable packages

This should eventually just be s2i, but until then...

Author: yuvipanda

images/singleuser-sample/Dockerfile

@@ -4,12 +4,17 @@ RUN apt-get update && \
     apt-get install --yes --no-install-recommends python3 python3-venv && \
     apt-get purge && apt-get clean
 
+RUN adduser --disabled-password --gecos "Default Jupyter user" jovyan
+
+RUN mkdir -p /srv/venv && chown -R jovyan:jovyan /srv/venv
+
+USER jovyan
+
 RUN python3 -m venv /srv/venv
 RUN /srv/venv/bin/pip3 install --no-cache-dir notebook ipykernel jupyterhub
 
-ENV HOME /home/jovyan
-ENV USER jovyan
 ENV PATH /srv/venv/bin:$PATH
+
 WORKDIR /home/jovyan
 
 EXPOSE 8888