Add Dockerfile for backend

api/Dockerfile

+# Pin version
+FROM node:14.8.0
+
+# Create app directory
+WORKDIR /usr/src/app
+
+# Install app dependencies
+COPY package*.json ./
+RUN npm ci --only=production
+
+# Bundle app source
+COPY . .
+
+EXPOSE 8888
+
+CMD [ "npm", "start" ]