Add builder Docker image

samples/19.a.single-sign-on-for-enterprise-apps/Dockerfile

@@ -0,0 +1,31 @@
+# Builder is based on Node.js 12 image
+# This builder image will build HTML and JavaScript code out of the create-react-app project
+FROM node:12 AS builder-web
+WORKDIR /var/web/
+
+# Copy the web app code to /var/web/
+# We excluded /.env and /node_modules/ via .dockerignore
+ADD app/ /var/web/
+
+# Doing a fresh "npm install" on build to make sure the image is reproducible
+RUN npm ci
+
+# Build the web app code via create-react-app and react-scripts
+RUN npm run build
+
+FROM node:12
+
+ADD bot/ /var/bot/
+ADD rest-api/ /var/web/
+COPY --from=builder-web /var/web/build/ /var/web/public/
+
+WORKDIR /var/bot/
+RUN npm ci
+
+WORKDIR /var/web/
+RUN npm ci
+
+WORKDIR /var/
+RUN tar -cf build.tgz bot web
+
+ENTRYPOINT sh