router needs to find a component to render. It is called once per router path changes, but not on subsequent redraws while on the same path. It can be used to run logic before a component initializes (for example authentication logic, data preloading, redirection analytics tracking, etc)</p>
<p>This method also allows you to asynchronously define what component will be rendered, making it suitable for code splitting and asynchronous module loading. To render a component asynchronously return a promise that 