Mapping Routes in React Router

In larger applications, routes quickly get repetitive, verbose, and repetitive. 😉

// App.js
class App extends Component {
  render() {
    return (
      <BrowserRouter>
        <div>
          <Route exact path="/" component={HomePage} />
          <Route exact path="/Teachers" component={TeacherListPage} />
          <Route exact path="/Teachers/:teacherId" component={TeacherPage} />
          <Route exact path="/Teachers/:teacherId/Classes" component={TaughtClassesPage} />
        {/* And on and on for classes, grades, students, et cetera. */}
        </div>
      </BrowserRouter>
    );
  }
}

It’s a huge brick of text in the middle of your render. It works, but it doesn’t look too good. Previous versions of React Router represented routes as objects; while that syntax is gone with React Router 4, it’s pretty easy to throw together something similar.

You probably noticed that routes tend to take the same kind of props. Let’s represent them as objects:

// You can declare this in `App.js`, but it might
// be better to move it to its own file.

const routes = [{
  path: '/',
  component: HomePage,
}, {
  path: '/Teachers',
  component: TeacherListPage,
}, {
  path: '/Teachers/:teacherId',
  component: TeacherPage,
}, {
  path: '/Teachers/:teacherId/Classes',
  component: TaughtClassesPage,
}, /* And so on. */];

Using this object, you can simplify App:

class App extends Component {
  render() {
    const routeComponents = routes.map(({path, component}, key) => <Route exact path={path} component={component} key={key} />);
    return (
      <BrowserRouter>
        {routeComponents}
        </div>
      </BrowserRouter>
    );
  }
}