Frequently Asked Questions

Where are Babel, ESLint and stylelint configured?

In package.json

Where are the files coming from when I run npm start?

In development Webpack compiles your application runs it in-memory. Only when you run npm run build will it write to disk and preserve your bundled application across computer restarts.

How do I fix Error: listen EADDRINUSE 127.0.0.1:3000?

This simply means that there's another process already listening on port 3000. The fix is to kill the process and rerun npm start.

OS X / Linux:

1. Find the process id (PID):

   ps aux | grep node
   

   This will return the PID as the value following your username:

   janedoe    29811  49.1  2.1  3394936 356956 s004  S+    4:45pm   2:40.07 node server
   

2. Then run

   kill -9 YOUR_PID
   

   e.g. given the output from the example above, YOUR_PID is 29811, hence that would mean you would run kill -9 29811

Windows

1. Find the process id (PID):

   netstat -a -o -n
   

   This will return a list of running processes and the ports they're listening on:

   Proto     Local Address     Foreign Address   State       PID
   TCP       0.0.0.0:25        0.0.0.0:0         Listening   4196
   ...
   TCP       0.0.0.0:3000      0.0.0.0:0         Listening   28344
   

2. Then run

   taskkill /F /PID YOUR_PID
   

   e.g. given the output from the example above, YOUR_PID is 28344, hence that would mean you would run taskkill /F /PID 28344

Local webfonts not working for development

In development mode CSS sourcemaps require that styling is loaded by blob://, resulting in browsers resolving font files relative to the main document.

A way to use local webfonts in development mode is to add an absolute output.publicPath in webpack.dev.babel.js, with protocol.

// webpack.dev.babel.js

output: {
  publicPath: 'http://127.0.0.1:3000/',
  /* … */
},

Non-route containers

Note: Container will always be nested somewhere below a route. Even if there's dozens of components in between, somewhere up the tree will be route. (maybe only "/", but still a route)

Where do I put the reducer?

While you can include the reducer statically in reducers.js, we don't recommend this as you lose the benefits of code splitting. Instead, add it as a composed reducer. This means that you pass actions onward to a second reducer from a lower-level route reducer like so:

// Main route reducer

function myReducerOfRoute(state, action) {
  switch (action.type) {
    case SOME_OTHER_ACTION:
      return someOtherReducer(state, action);
  }
}

That way, you still get the code splitting at route level, but avoid having a static combineReducers call that includes all of them by default.

See this and the following lesson of the egghead.io Redux course for more information about reducer composition!

How do I run the saga?

Since a container will always be within a route, one we can simply add it to the exported array in sagas.js of the route container somewhere up the tree:

// /containers/SomeContainer/sagas.js

import { someOtherSagaFromNestedContainer } from './containers/SomeNestedContainer/sagas';

function* someSaga() { /* … */ }

export default [
  someSaga,
  someOtherSagaFromNestedContainer,
];

Or, if you have multiple sagas in the nested container:

// /containers/SomeContainer/sagas.js

import nestedContainerSagas from './containers/SomeNestedContainer/sagas';

function* someSaga() { /* … */ }

export default [
  someSaga,
  ...nestedContainerSagas,
];

Using this boilerplate with WebStorm

WebStorm is a powerful IDE, and why not also use it as debugger tool? Here is the steps

1. Install JetBrain Chrome Extension
2. Setting up the PORT
3. Change WebPack devtool config to source-map (This line)
4. Run web server (npm run start)
5. Create Run Configuration (Run > Edit Configurations)
6. Add new JavaScript Debug
7. Setting up URL
8. Start Debug (Click the green bug button)
9. Edit Run Configuration Again
10. Mapping Url as below picture

* Map your `root` directory with `webpack://.` (please note the last dot)
* Map your `build` directory with your root path (e.g. `http://localhost:3000`)

11. Hit OK and restart debugging session

Troubleshooting

1. You miss the last . (dot) in webpack://.
2. The port debugger is listening tool and the JetBrain extension is mismatch.

Enable ESLint

ESLint help making all developer follow the same coding format. Please also setting up in your IDE, otherwise, you will fail ESLint test.

1. Go to WebStorm Preference
2. Search for ESLint
3. Click Enable