title: Can't complete npm install when directing Docker to local NPM packages
body: <p>I haven’t been able to find an answer to this question anywhere, so I’m hoping someone here might have run into a similar issue.</p>
  
  <p>I’m trying to containerize a NodeJS application, but run into this error during <code>RUN npm install</code>:</p>
  
  <blockquote>
    <p>npm ERR! Could not install from "packages/example-package" as it does
    not contain a package.json file</p>
  </blockquote>
  
  <p>The package in question is listed as a local dependency in my app’s package.json:</p>
  
  <pre><code>"dependencies": {
     "@example-name/example-package": "file:../example-package"   },
  </code></pre>
  
  <p>There are no issues running <code>npm install</code> outside of docker with these local file paths.</p>
  
  <p>I’ve tried copying the packages package.json file into the container, via the Dockerfile, like so:</p>
  
  <pre><code>COPY ./packages/example-package/package.json ./packages/example-package
  </code></pre>
  
  <p>The resulting error is:</p>
  
  <blockquote>
    <p>npm ERR! Could not install "packages/example-packages" as it is not a
    directory and is not a file with a name ending in .tgz, .tar.gz or
    .tar</p>
  </blockquote>
  
  <p>I’m at a loss as to where to go from here! Any suggestions?</p>