Framework
Version

Authenticated Routes

Authentication is an extremely common requirement for web applications. In this guide, we'll walk through how to use TanStack Router to build protected routes, and how to redirect users to login if they try to access them.

The route.beforeLoad Option

The route.beforeLoad option allows you to specify a function that will be called before a route is loaded. It receives all of the same arguments that the route.loader function does. This is a great place to check if a user is authenticated, and redirect them to a login page if they are not.

The beforeLoad function runs in relative order to these other route loading functions:

  • Route Matching (Top-Down)
    • route.params.parse
    • route.validateSearch
  • Route Loading (including Preloading)
    • route.beforeLoad
    • route.onError
  • Route Loading (Parallel)
    • route.component.preload?
    • route.load

It's important to know that the beforeLoad function for a route is called before any of its child routes' beforeLoad functions. It is essentially a middleware function for the route and all of its children.

If you throw an error in beforeLoad, none of its children will attempt to load.

Redirecting

While not required, some authentication flows require redirecting to a login page. To do this, you can throw a redirect() from beforeLoad:

tsx
// src/routes/_authenticated.tsx
export const Route = createFileRoute('/_authenticated')({
  beforeLoad: async ({ location }) => {
    if (!isAuthenticated()) {
      throw redirect({
        to: '/login',
        search: {
          // Use the current location to power a redirect after login
          // (Do not use `router.state.resolvedLocation` as it can
          // potentially lag behind the actual current location)
          redirect: location.href,
        },
      })
    }
  },
})
// src/routes/_authenticated.tsx
export const Route = createFileRoute('/_authenticated')({
  beforeLoad: async ({ location }) => {
    if (!isAuthenticated()) {
      throw redirect({
        to: '/login',
        search: {
          // Use the current location to power a redirect after login
          // (Do not use `router.state.resolvedLocation` as it can
          // potentially lag behind the actual current location)
          redirect: location.href,
        },
      })
    }
  },
})

Tip

The redirect() function takes all of the same options as the navigate function, so you can pass options like replace: true if you want to replace the current history entry instead of adding a new one.

Once you have authenticated a user, it's also common practice to redirect them back to the page they were trying to access. To do this, you can utilize the redirect search param that we added in our original redirect. Since we'll be replacing the entire URL with what it was, router.history.push is better suited for this than router.navigate:

tsx
router.history.push(search.redirect)
router.history.push(search.redirect)

Non-Redirected Authentication

Some applications choose to not redirect users to a login page, and instead keep the user on the same page and show a login form that either replaces the main content or hides it via a modal. This is also possible with TanStack Router by simply short circuiting rendering the <Outlet /> that would normally render the child routes:

tsx
// src/routes/_authenticated.tsx
export const Route = createFileRoute('/_authenticated')({
  component: () => {
    if (!isAuthenticated()) {
      return <Login />
    }

    return <Outlet />
  },
})
// src/routes/_authenticated.tsx
export const Route = createFileRoute('/_authenticated')({
  component: () => {
    if (!isAuthenticated()) {
      return <Login />
    }

    return <Outlet />
  },
})

This keeps the user on the same page, but still allows you to render a login form. Once the user is authenticated, you can simply render the <Outlet /> and the child routes will be rendered.

Authentication using React context/hooks

If your authentication flow relies on interactions with React context and/or hooks, you'll need to pass down your authentication state to TanStack Router using router.context option.

Important

React hooks are not meant to be consumed outside of React components. If you need to use a hook outside of a React component, you need to extract the returned state from the hook in a component that wraps your <RouterProvider /> and then pass the returned value down to TanStack Router.

We'll cover the router.context options in-detail in the Router Context section.

Here's an example that uses React context and hooks for protecting authenticated routes in TanStack Router. See the entire working setup in the Authenticated Routes example.

  • src/routes/__root.tsx
tsx
import { createRootRouteWithContext } from '@tanstack/react-router'

interface MyRouterContext {
  // The ReturnType of your useAuth hook or the value of your AuthContext
  auth: AuthState
}

export const Route = createRootRouteWithContext<MyRouterContext>()({
  component: () => <Outlet />,
})
import { createRootRouteWithContext } from '@tanstack/react-router'

interface MyRouterContext {
  // The ReturnType of your useAuth hook or the value of your AuthContext
  auth: AuthState
}

export const Route = createRootRouteWithContext<MyRouterContext>()({
  component: () => <Outlet />,
})
  • src/router.tsx
tsx
import { createRouter } from '@tanstack/react-router'

import { routeTree } from './routeTree.gen'

export const router = createRouter({
  routeTree,
  context: {
    // auth will initially be undefined
    // We'll be passing down the auth state from within a React component
    auth: undefined!,
  },
})
import { createRouter } from '@tanstack/react-router'

import { routeTree } from './routeTree.gen'

export const router = createRouter({
  routeTree,
  context: {
    // auth will initially be undefined
    // We'll be passing down the auth state from within a React component
    auth: undefined!,
  },
})
  • src/App.tsx
tsx
import { RouterProvider } from '@tanstack/react-router'

import { router } from './router'

function InnerApp() {
  const auth = useAuth()
  return <RouterProvider router={router} context={{ auth }} />
}

function App() {
  return (
    <AuthProvider>
      <InnerApp />
    </AuthProvider>
  )
}
import { RouterProvider } from '@tanstack/react-router'

import { router } from './router'

function InnerApp() {
  const auth = useAuth()
  return <RouterProvider router={router} context={{ auth }} />
}

function App() {
  return (
    <AuthProvider>
      <InnerApp />
    </AuthProvider>
  )
}

Then in the authenticated route, you can check the auth state using the beforeLoad function, and throw a redirect() to your Login route if the user is not signed-in.

  • src/routes/dashboard.route.tsx
tsx
import { createFileRoute, redirect } from '@tanstack/react-router'

export const Route = createFileRoute('/dashboard')({
  beforeLoad: ({ context, location }) => {
    if (!context.auth.isAuthenticated) {
      throw redirect({
        to: '/login',
        search: {
          redirect: location.href,
        },
      })
    }
  },
})
import { createFileRoute, redirect } from '@tanstack/react-router'

export const Route = createFileRoute('/dashboard')({
  beforeLoad: ({ context, location }) => {
    if (!context.auth.isAuthenticated) {
      throw redirect({
        to: '/login',
        search: {
          redirect: location.href,
        },
      })
    }
  },
})

You can optionally, also use the Non-Redirected Authentication approach to show a login form instead of calling a redirect.

This approach can also be used in conjunction with Layout or Parent Routes to protect all routes under a specific layout.

Subscribe to Bytes

Your weekly dose of JavaScript news. Delivered every Monday to over 100,000 devs, for free.

Bytes

No spam. Unsubscribe at any time.