docker: Add entrypoint.sh

Apparently I forgot to add this file in previous commits - the initial
shape is provided by @valberg, I added some defaults for
POSTGRES_{HOST,PORT}.

docker/Dockerfile

@@ -39,5 +39,5 @@ RUN mkdir /app/static && chown www:www /app/static
 ARG BUILD
 ENV BUILD ${BUILD}
 
-ENTRYPOINT ["/entrypoint.sh"]
+ENTRYPOINT ["./entrypoint.sh"]
 CMD ["uvicorn", "config.asgi:application", "--host", "0.0.0.0", "--port", "8080", "--workers", "3", "--lifespan", "off"]

entrypoint.sh

@@ -0,0 +1,21 @@
+#!/bin/sh
+ 
+echo "Waiting for postgres..."
+ 
+POSTGRES_PORT=${POSTGRES_PORT:-5432}
+POSTGRES_HOST=${POSTGRES_HOST:-localhost}
+
+while ! nc -z "$POSTGRES_HOST" "$POSTGRES_PORT"; do
+  sleep 0.1
+done
+ 
+echo "PostgreSQL started"
+ 
+# Only migrate and collectstatic if we are NOT in development
+if [ -z "$DEBUG" ]; then
+  python manage.py migrate
+  python manage.py collectstatic --no-input;
+fi
+ 
+exec "$@"
+