localhost:3000 does not work

[Deleted user]

after I npm install，all package is installed successfully now
and then npm run dev,localhost:3000 in browser,but the page alway loading.chrome show 'ERR_EMPTY_RESPONSE'

here is the command line log

$ npm run dev

> hackernews@0.5.0 dev C:\My\work\React\hackernews-react-graphql
> babel-node src/server.js

> Using external babel configuration
> Location: "C:\My\work\React\hackernews-react-graphql\.babelrc"
 DONE  Compiled successfully in 2071ms18:25:15

> App ready on http://localhost:3000
> GraphQL Ready on http://localhost:3000/graphql
Dev: true
> Building page: /
 DONE  Compiled successfully in 2359ms18:25:20

Warning: Failed prop type: You provided a `value` prop to a form field without an `onChange` handler. This will render a read-only field. If the field should be mutable use `defaultValue`. Otherwise, set either `onChange` or `readOnly`.
    in input
    in form
    in center
    in td
    in tr
    in Footer
    in tbody
    in table
    in center
    in Main
    in Query
    in Apollo(Main)
    in Unknown
    in ApolloProvider
    in RenderPromisesProvider
 WAIT  Compiling...18:25:21

 DONE  Compiled successfully in 105ms18:25:22

why?thank you!