title: Docker fails to copy nginx conf
body: <p>I have Dockerfile to deploy my frontend, which is in react.
  This is what I have in my dockerfile.</p>
  
  <pre><code>  # Stage 1
  FROM node:8 as react-build
  WORKDIR /app
  COPY . ./
  RUN yarn
  RUN yarn build
  
  # Stage 2 - the production environment
  FROM nginx:alpine
  COPY nginx.conf /etc/nginx/conf.d/default.conf
  COPY --from=react-build /app/build /usr/share/nginx/html
  EXPOSE 80
  CMD ["nginx", "-g", "daemon off;"]
  </code></pre>
  
  <p>When I run <code>$ docker build . -t frontend</code>
  I am getting an error on step 8, which fails to copy the nginx.conf</p>
  
  <pre><code>Step 8/10 : COPY --from=react-build /app/build /usr/share/nginx/html
  COPY failed: stat /var/lib/docker/overlay2/fef4deafd532bb0aa7eaea50ae25412e93f7972eab3a0579fe494de444d86a0b/merged/app/build: no such file or directory
  </code></pre>
  
  <p>But the nginx conf file exists, and I don't understand what's going on there, can somebody enlighten me what's going on?
  <a href="http://prntscr.com/l2to47" rel="nofollow noreferrer">http://prntscr.com/l2to47</a> This is my project structure, which clearly says there are nginx.conf but Docker can't find it.</p>