Router Hooks

The Blits router supports hooks that allow you to execute code at specific points during the navigation process.

Hooks are defined per route in the optional hooks key within the Route configuration object.

Currently, the Blits router only supports the before hook, with additional hooks planned for future releases.

Before hook

The before hook is executed before the navigation occurs. It can be used for checks, such as verifying user authentication for a specific route, for pre-fetching data, or for executing logic like sending stats beacons.

The before hook is defined as a function that receives 2 arguments: the Route object that is being navigated to. And the Route object that is being navigated away from.

export default Blits.Application({
  // ...
  routes: [
      {
        path: '/',
        component: Home,
        hooks: {
          before(to, from) {
            // custom logic
          }
        }
      }
  ],
  // ...
})

The before hook can optionally return a value, which will influence the behaviour of the route change:

• when false is returned, the router will fail to finish the routing, and act as if no matching route was found
• when a string is returned, the router will interpret this a new route path to redirect to
• when an object is returned, the router will interpret this as a route object, allowing to modify (or completely replace) the route object being navigated to

Returning an object is a simple, yet powerful, mechanism to add advanced runtime configuration to your routes. A common scenario is to overwrite certain parts of the route object provided in the to-argument, such as the route options (such as inHistory or stayAlive) or define conditional page transitions.

It's also possible to add custom data to the route object in the key object. Custom data should be an object literal. When the new page loads, the keys in the data object are injected into the Component as props.

export default Blits.Application({
  // ...
  routes: [
      {
        path: '/video/details/:id',
        component: Details,
        hooks: {
          before(to, from) {
            // redirect to an error page when id is not a number
            if(isNaN(to.params.id)) {
              return '/not-valid'
            }
            // set a different transition when navigating from home page
            if(from && from.path === '/home') {
              to.transition = slideInTransition
            }
            // add custom data
            to.data.title = 'Hello World'
            // finally return the modified route object
            return to
          }
        }
      }
  ],
  // ...
})