Preventing Multiple Redirects and Code Query Changes in Nuxt 3 with Auth0-vue

Below is a set of ideas and possible solutions based on your description and configuration.

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Possible Cause

With the global route middleware applying on every navigation (including the callback route) the following may be happening:

• The callback route (with the code query parameter) is being guarded like every other route.
• Calling checkSession on the URL that still contains the Auth0 code triggers another login redirect because the session isn’t finalized yet.
• As a result, the application performs multiple reloads and the code parameter changes each time.

This issue can occur when the middleware does not exclude the callback route from re-triggering login logic.

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Possible Solutions

1. Exclude the Callback Route from Global Auth Middleware

   Do not run your authentication check (and redirect) on the callback route. You can modify your middleware to check the current route’s pathname (or name) and skip running checkSession when you are already handling the callback.

2. Clean Up the Callback URL After Processing

   Ensure that when Auth0 processes the callback, it cleans up the query parameters (code, state) so they don’t trigger further redirects.

3. Conditional Check for Redirection

   Confirm that the login trigger isn’t repeatedly invoked. For instance, check if the current route is not already the callback route before calling loginWithRedirect.

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Example Modified Code

Below is an example of how you might adjust your middleware to exclude the callback path:

TYPESCRIPTCopied
export default defineNuxtPlugin((nuxtApp) => {
  const config = useRuntimeConfig();
  const auth0 = createAuth0({
    domain: config.public.AUTH0_DOMAIN || '',
    clientId: config.public.AUTH0_CLIENT_ID || '',
    authorizationParams: {
      redirect_uri: config.public.AUTH0_REDIRECT_URL || '',
      audience: config.public.AUTH0_AUDIENCE || ''
    }
  });

  nuxtApp.vueApp.use(auth0);

  addRouteMiddleware(
    'auth',
    async (to) => {
      // Exclude the callback route from checking authentication
      if (to.path === '/callback') return;

      if (process.client) {
        await auth0.checkSession();
        if (!auth0.isAuthenticated.value) {
          auth0.loginWithRedirect({
            appState: { target: '/callback' }
          });
        }
      }
    },
    { global: true }
  );

  return {
    provide: {
      auth0
    }
  };
});

In this snippet:

• The middleware checks if the current route to.path is /callback and returns early if so.
• This prevents applying the authentication check on the callback route, avoiding a loop of redirects.

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Additional Tips

• Review the Auth0 Documentation: Make sure that the handling of the callback URL matches current library recommendations.
• Test in Different Environments: Sometimes issues might be environment-specific, so testing locally vs. production can shed light on any discrepancies.
• Upgrade Dependencies: Ensure you’re using compatible versions of Nuxt 3 and auth0-vue, as library updates might have fixes related to callback handling.

By following these recommendations, you should be able to stop the multiple reloads and have a single, clean redirect after a successful login.