DecoratingComponents.md

Decorate Components with Data

Suppose you have the following Stargazer component to render a Github user's profile:

export default class Stargazer extends React.Component {
  static propTypes = {
    user: React.PropTypes.object.isRequired,
  }

  render() {
    /* Render profile from this.props.user */
  }
}

In 2014, you would use componentWillMount to fire off an AJAX request for the profile, then use setState to trigger a re-render with the data.

This won't work on the server-side, and it's annoying to test.

According to most universal boilerplates, we'd put static fetchData() function in our component for a middleware or library to handle, rendering the component when data comes back.

This only works for fat controllers at the top of your application, usually defined by a React Router <Route>.

Instead, let's decorate it:

import { resolve } from "react-resolver";

// Assuming this _is_ from <Route> component matching `/users/ericclemmons`
@resolve("user", function(props) {
  return axios
    .get(`https://api.github.com/users/${props.params.user}`)
    .then((response) => response.data)
  ;
})
export default class Stargazer extends React.Component {

Or, if ES7 decorators aren't your bag:

class Stargazer extends React.Component {
  ...
}

export default resolve("user", function(props) {
  ...
})(Stargazer);