[docker] Download IHM from Pypy or reference git repo;

This creates two modes to run the Docker image:
- either in non-NIGHTLY mode, the latest version will be installed from
pypy.
- or in Nightly mode, it will clone the repository and update it every
time the instance is restarted.

It also updates Python to 3.7, for additional goodness.

Dockerfile

@@ -1,18 +1,7 @@
-FROM python:3.6-alpine
+FROM python:3.7-alpine
 
-RUN apk update && apk add gcc libc-dev libffi-dev openssl-dev &&\
-    mkdir /ihatemoney &&\
-    mkdir -p /etc/ihatemoney &&\
-    pip install --no-cache-dir gunicorn pymysql
-
-COPY . /ihatemoney
-ARG INSTALL_FROM_PYPI="False"
-RUN if [ "$INSTALL_FROM_PYPI" = True ]; then\
-    pip install --no-cache-dir ihatemoney ; else\
-    pip install --no-cache-dir -e /ihatemoney ; \
-    fi
-
-ENV DEBUG="False" \
+ENV NIGHTLY="" \
+    DEBUG="False" \
     SQLALCHEMY_DATABASE_URI="sqlite:////database/ihatemoney.db" \
     SQLALCHEMY_TRACK_MODIFICATIONS="False" \
     SECRET_KEY="tralala" \
@@ -21,13 +10,19 @@ ENV DEBUG="False" \
     MAIL_PORT=25 \
     MAIL_USE_TLS=False \
     MAIL_USE_SSL=False \
-    MAIL_USERNAME=None \
-    MAIL_PASSWORD=None \
+    MAIL_USERNAME= \
+    MAIL_PASSWORD= \
     ACTIVATE_DEMO_PROJECT="True" \
     ADMIN_PASSWORD="" \
     ALLOW_PUBLIC_PROJECT_CREATION="True" \
     ACTIVATE_ADMIN_DASHBOARD="False"
 
+RUN apk update && apk add git gcc libc-dev libffi-dev openssl-dev wget &&\
+    mkdir -p /etc/ihatemoney &&\
+    pip install --no-cache-dir gunicorn pymysql;
+
+COPY ./conf/entrypoint.sh /entrypoint.sh
+
 VOLUME /database
 EXPOSE 8000
-ENTRYPOINT ["/ihatemoney/conf/confandrun.sh"]
+ENTRYPOINT ["/entrypoint.sh"]

conf/entrypoint.sh

@@ -1,4 +1,8 @@
 #!/bin/sh
+
+# Fail the whole script on the first failure.
+set -e
+
 cat <<EOF > /etc/ihatemoney/ihatemoney.cfg
 DEBUG = $DEBUG
 SQLALCHEMY_DATABASE_URI = "$SQLALCHEMY_DATABASE_URI"
@@ -17,6 +21,25 @@ ADMIN_PASSWORD = '$ADMIN_PASSWORD'
 ALLOW_PUBLIC_PROJECT_CREATION = $ALLOW_PUBLIC_PROJECT_CREATION
 ACTIVATE_ADMIN_DASHBOARD = $ACTIVATE_ADMIN_DASHBOARD
 EOF
+
+if [ ! -z "$NIGHTLY" ]; then
+    # Clone or update repository into /ihatemoney.
+    if [ ! -d /ihatemoney/.git ]; then
+        echo "Cloning..."
+        git clone --depth 1 https://github.com/spiral-project/ihatemoney /ihatemoney
+        echo "Done cloning."
+    else
+        cd /ihatemoney
+        echo "Updating..."
+        git pull || echo "Couldn't update; maybe Github is unreachable?"
+        echo "Done updating."
+    fi
+    pip install --no-cache-dir -e /ihatemoney
+else
+    # Get the latest release from PyPy.
+    pip install --no-cache-dir --upgrade ihatemoney
+fi
+
 # Start gunicorn without forking
 exec gunicorn ihatemoney.wsgi:application \
      -b 0.0.0.0:8000 \