title: Running React app in Docker container not running correctly
body: <p>I have a small React app that I would like to run in a Docker container. I have the following Dockerfile filled out like this:</p>
  
  <pre><code># base image
  FROM node:9.6.1
  
  # set working directory
  RUN mkdir /app
  WORKDIR /app
  
  ENV PATH /app/node_modules/.bin:$PATH
  
  # install and cache app dependencies
  COPY package-lock.json /app/package-lock.json
  COPY package.json /app/package.json
  
  COPY . /app
  
  RUN npm install
  
  # start app
  CMD ["npm", "start"]
  </code></pre>
  
  <p>After doing a build, I was able to correctly (I think) create an image.</p>
  
  <pre><code>&gt;docker image list
  REPOSITORY           TAG                 IMAGE ID            CREATED             SIZE
  notes                latest              e4ccada07b84        18 hours ago        846MB
  </code></pre>
  
  <p>However, when I run on the image, it does run <code>npm start</code>, but not in the port I specified and if I go to the URL it provides it can't connect to anything.</p>
  
  <pre><code>&gt;docker run -p 3030:3030  notes:latest
  
  You can now view notes in the browser.
  
    Local:            http://localhost:3000/
    On Your Network:  http://172.17.0.4:3000/
  
  Note that the development build is not optimized.
  To create a production build, use npm run build.
  </code></pre>
  
  <p>What am I missing to get this running in a container correctly?</p>