Use alpine images instead of Python. (#290)

* Use alpine images instead of Python.

* Minor fix to use python3 -m pip

* Fix settings for paintstore.

core/Dockerfile

@@ -1,4 +1,4 @@
-FROM python:3.6-alpine
+FROM alpine:3.8
 
 MAINTAINER Abhilash Raj
 
@@ -7,10 +7,11 @@ COPY docker-entrypoint.sh /usr/local/bin/
 
 #Install all required packages, add user for executing mailman and set execution rights for startup script
 RUN apk update \
-    && apk add --virtual build-deps gcc python3-dev musl-dev postgresql-dev libffi-dev \
-    && apk add bash su-exec postgresql-client mysql-client curl \
-	&& pip install -U pip \
-    && pip install psycopg2 \
+	&& apk add --virtual build-deps gcc python3-dev musl-dev postgresql-dev \
+	   libffi-dev \
+	&& apk add --no-cache bash su-exec postgresql-client mysql-client curl python py3-setuptools \
+	&& python3 -m pip install -U pip \
+    && python3 -m pip install psycopg2 \
                    mailman==3.2 \
                    mailman-hyperkitty==1.1.0 \
                    pymysql \

core/Dockerfile.dev

@@ -1,4 +1,4 @@
-FROM python:3.6-alpine
+FROM alpine:3.8
 
 MAINTAINER Abhilash Raj
 
@@ -13,11 +13,12 @@ ARG MM3_HK_REF
 #Install all required packages, add user for executing mailman and set execution
 #rights for startup script
 RUN apk update \
-    && apk add --virtual build-deps gcc python3-dev musl-dev postgresql-dev git libffi-dev \
-    && apk add bash su-exec postgresql-client mysql-client curl \
-    && pip install -U psycopg2 pymysql \
-                      git+https://gitlab.com/mailman/mailman@${CORE_REF} \
-											git+https://gitlab.com/mailman/mailman-hyperkitty@${MM3_HK_REF} \
+	&& apk add --no-cache --virtual build-deps gcc python3-dev musl-dev \
+   	    postgresql-dev git libffi-dev  \
+    && apk add --no-cache bash su-exec postgresql-client mysql-client curl python3 py3-setuptools \
+    && python3 -m pip install -U psycopg2 pymysql \
+        git+https://gitlab.com/mailman/mailman@${CORE_REF} \
+        git+https://gitlab.com/mailman/mailman-hyperkitty@${MM3_HK_REF} \
     && apk del build-deps \
     && adduser -S mailman
 

core/docker-entrypoint.sh

@@ -4,7 +4,7 @@ set -e
 function wait_for_postgres () {
 	# Check if the postgres database is up and accepting connections before
 	# moving forward.
-	# TODO: Use python's psycopg2 module to do this in python instead of
+	# TODO: Use python3's psycopg2 module to do this in python3 instead of
 	# installing postgres-client in the image.
 	until psql $DATABASE_URL -c '\l'; do
 		>&2 echo "Postgres is unavailable - sleeping"