Add a Dockefile

Dockerfile

+FROM python:3-alpine AS python_build
+COPY requirements.txt /requirements.txt
+RUN apk add --no-cache build-base python3-dev openssl-dev libffi-dev xmlsec xmlsec-dev  \
+ && pip install -r /requirements.txt
+
+FROM node:alpine AS assets_build
+COPY package.json webpack.config.js /
+RUN npm install
+COPY assets /assets
+RUN /node_modules/.bin/webpack-cli
+
+FROM python:3-alpine
+RUN apk add --no-cache xmlsec \
+ && mkdir /app
+WORKDIR /app
+COPY trurt /app/trurt
+COPY --from=python_build /usr/local/ /usr/local/
+COPY --from=assets_build /trurt/static /app/trurt/static
+CMD gunicorn -w 4 -b :80 --access-logfile - --error-logfile - --preload 'trurt:create_app()'