perf: download chromium as a apt package

We've moved the chromium download from the node_nodules to an OS-level
download.  This ensures that don't spend a long in the node_modules
section of the build.

Dockerfile

@@ -1,33 +1,40 @@
 # define base image
-FROM node:lts
+FROM node:lts-slim
+
+# download all the missing dependencies for chromium, plus chromium itself
+RUN apt-get update && apt-get install -y \
+  ca-certificates fonts-liberation gconf-service \
+  libappindicator1 libasound2 libatk-bridge2.0-0 libatk1.0-0 libc6 libcairo2  \
+  libcups2 libdbus-1-3 libexpat1 libfontconfig1 libgbm1 libgcc1 libgconf-2-4 \
+  libgdk-pixbuf2.0-0 libglib2.0-0 libgtk-3-0 libnspr4 libnss3 libpango-1.0-0 \
+  libpangocairo-1.0-0 libstdc++6 libx11-6 libx11-xcb1 libxcb1 libxcomposite1 \
+  libxcursor1 libxdamage1 libxext6 libxfixes3 libxi6 libxrandr2 libxrender1 \
+  libxss1 libxtst6 lsb-release libxshmfence1 chromium -y
 
 # ENV NODE_ENV=production
 ENV YARN_VERSION 1.22.17
+ENV PUPPETEER_SKIP_CHROMIUM_DOWNLOAD 1
 RUN yarn policies set-version $YARN_VERSION
+ENV CHROME_BIN /usr/bin/chromium
 
 # define working directory inside the container
 WORKDIR /usr/src/app
 
-# Copy the package.json file to the project directory
-COPY package.json .
-COPY yarn.lock .
-COPY .env .
-
-# install all the dependencies
-RUN yarn --frozen-lockfile
-
 # Copy all the source code from host machine to the container project directory
 COPY . .
 
-RUN yarn build
+# install all the dependencies
+RUN yarn --frozen-lockfile && yarn build
+
+# yarn build creates the bin/ folder
 
 COPY .env bin/
 
 # change directory to the bin diretory
 WORKDIR /usr/src/app/bin/
 
-# define the start up command of the container to run the server
-CMD ["node", "server/app.js"]
-
 # ensure this container runs as the user "node"
 USER node
+
+# define the start up command of the container to run the server
+CMD ["node", "server/app.js"]