react-webpack-node/app/middlewares/preRenderMiddleware.js

A simple Node.js app using Express 4 with Webpack, React, alt, ImmutableJS

/**
* This looks at static needs parameter in components
* and waits for the promise to be fullfilled.
*
* It is used to make sure server side rendered pages
* wait for APIs to resolve before returning res.end().
*
* As seen in: https://github.com/caljrimmer/isomorphic-redux-app
*/

export default function preRenderMiddleware(dispatch, components, params) {
  return Promise.all(
    components.reduce((previous, current) => {
      return (current.need || []).concat(previous);
    }, []).map(need => dispatch(need(params)))
  );
}