change current component used by `router-view` without changing current URL

Explanation of the problem

In a given scenario, there is a requirement to handle failed data fetching from a backend API. The desired behavior is to route to an error page without changing the current location and provide a prompt to the user, suggesting they refresh the page to retry the operation. It is important to ensure that refreshing the page while on the error page does not redirect back to the error page. Another common use case is to display the login page if the user is not logged in, without redirecting them to a separate login URL.

Troubleshooting with the Lightrun Developer Observability Platform

Getting a sense of what’s actually happening inside a live application is a frustrating experience, one that relies mostly on querying and observing whatever logs were written during development.
Lightrun is a Developer Observability Platform, allowing developers to add telemetry to live applications in real-time, on-demand, and right from the IDE.

• Instantly add logs to, set metrics in, and take snapshots of live applications
• Insights delivered straight to your IDE or CLI
• Works where you do: dev, QA, staging, CI/CD, and production

Start for free today

Problem solution for: change current component used by `router-view` without changing current URL

To address this requirement, a possible solution is to modify the code in the App.vue component. The proposed implementation involves using conditional rendering with the help of the v-if and v-else directives. By introducing a new component, referred to as forceShowPage, the desired behavior can be achieved. If forceShowPage is truthy, the custom component will be displayed, and if it is falsy, the regular router-view component will be rendered. However, this approach presents a challenge as the nested routes’ layout components cannot be reused.

To overcome this limitation, a suggested API enhancement is to introduce a new prop called route for the <RouterView> component. This prop would allow overriding what is displayed within the <router-view> based on the provided route object, similar to the behavior in Vue Router v4. The proposed API enhancement aligns with the existing tests available in the Vue Router repository for handling modal scenarios. By introducing the route prop, developers would have more flexibility and control over the content rendered within the <router-view> component, enabling them to achieve the desired behavior while still utilizing nested routes and layout components effectively.

Here’s an example of how the proposed API enhancement could be used:

<!-- App.vue -->
<template>
  <router-view :route="customRoute"></router-view>
</template>

<script>
export default {
  computed: {
    customRoute() {
      // Logic to determine the custom route object based on conditions
      // e.g., failed API fetch or user not logged in
      // Return the appropriate route object
    }
  }
}
</script>

By introducing the route prop and implementing the custom route logic within the App.vue component, developers can effectively control the content displayed within the <router-view> component based on specific conditions, allowing for the desired behavior of handling errors or displaying login pages without changing the URL or compromising the reusability of layout components.

const router = new VueRouter({
  routes: [
    {
      path: '/user/:id',
      component: User,
      beforeEnter: (to, from, next) => {
        // Perform custom logic based on the user ID
        const userId = to.params.id;
        if (userId === 'admin') {
          // Redirect to a different route
          next('/admin');
        } else {
          // Proceed to the intended route
          next();
        }
      }
    }
  ]
});

<!-- App.vue -->
<template>
  <div>
    <h1>My App</h1>
    <router-view></router-view>
  </div>
</template>

<!-- ParentComponent.vue -->
<template>
  <div>
    <h2>Parent Component</h2>
    <router-view></router-view>
  </div>
</template>

<!-- ChildComponent.vue -->
<template>
  <div>
    <h3>Child Component</h3>
    <!-- Content specific to the child component -->
  </div>
</template>

// Inside a Vue component method
this.$router.push('/dashboard'); // Navigate to the '/dashboard' route

import Vue from 'vue';
import VueRouter from 'vue-router';
import Home from './components/Home.vue';
import About from './components/About.vue';

Vue.use(VueRouter);

const routes = [
  { path: '/', component: Home },
  { path: '/about', component: About }
];

const router = new VueRouter({
  routes
});

new Vue({
  router
}).$mount('#app');

const routes = [
  { path: '/user/:id', component: User }
];

const router = new VueRouter({
  routes
});

router.beforeEach((to, from, next) => {
  // Check if the user is authenticated
  if (to.meta.requiresAuth && !isAuthenticated()) {
    // Redirect to the login page
    next('/login');
  } else {
    // Proceed with the navigation
    next();
  }
});