title: mime.lookup is not a function in expressjs run inside docker
body: <p>I have a docker image running a node process. It is listening to a particular port. When i am trying to access the port using curl or through browser request, I am getting following error - </p>
  
  <p>TypeError: mime.lookup is not a function
      at ServerResponse.contentType (/E:/Saurabh/node_modules/express/lib/response.js:592:12)
      at ServerResponse.send (/E:/Saurabh/node_modules/express/lib/response.js:145:14)
      at app.get (/E:/Saurabh/apis/index.js:26:6)
      at Layer.handle [as handle_request] (/E:/Saurabh/node_modules/express/lib/router/layer.js:95:5)
      at next (/E:/Saurabh/node_modules/express/lib/router/route.js:137:13)
      at Route.dispatch (/E:/Saurabh/node_modules/express/lib/router/route.js:112:3)
      at Layer.handle [as handle_request] (/E:/Saurabh/node_modules/express/lib/router/layer.js:95:5)
      at /E:/Saurabh/node_modules/express/lib/router/index.js:281:22
      at Function.process_params (/E:/Saurabh/node_modules/express/lib/router/index.js:335:12)
      at next (/E:/Saurabh/node_modules/express/lib/router/index.js:275:10)</p>
  
  <p>If i run same code without docker, then it works as expected.
  What can be the issue?</p>