Handling Signin and Signout

To signin your users, make sure you have at least one authentication method setup. You then need to build a button which will call the sign in function from your Auth.js framework package.

./components/auth/signin-button.tsx

import { signIn } from "@/auth.ts"
 
export function SignIn() {
  return (
    <form
      action={async () => {
        "use server"
        await signIn()
      }}
    >
      <button type="submit">Sign in</button>
    </form>
  )
}

In a client component, you can still use the imports from next-auth/react as they are marked with the "use client;" directive.

./components/auth/signin-button.tsx

import { signIn } from "next-auth/react"
 
export function SignIn() {
  return <Button onClick={() => signIn()}>Sign In</Button>
}

./components/auth/signin-button.tsx

import { signIn } from "next-auth/react"
 
export function SignIn() {
  return <Button onClick={() => signIn()}>Sign In</Button>
}

The SvelteKit client supports two signin and signout methods, one server-side using Form Actions, and one client-side using requests and redirects.

Form Action (Server-Side)

To signin your users using a SvelteKit form action, we can use the SignIn component exported from @auth/sveltekit/components.

src/routes/+page.svelte

<script lang="ts">
  import { SignIn } from "@auth/sveltekit/components"
</script>
 
<header>
  <nav>
    <SignIn>
      <span slot="submitButton">Sign In with GitHub</span>
    </SignIn>
  </nav>
</header>

This requires a server action at /signin, this path can be customized with the signInPage prop on the SignIn component.

src/routes/signin/+page.server.ts

import { signIn } from "../../auth"
import type { Actions } from "./$types"
 
export const actions: Actions = { default: signIn }

Client Side

Client-side is a bit simpler as we just need to import a button on:click handler from @auth/sveltekit/client.

src/routes/+page.svelte

<script lang="ts">
  import { signIn } from '@auth/sveltekit/client'
</script>
 
<div>
  <nav>
    <img src="/img/logo.svg" alt="Company Logo" />
    <button on:click={signIn}>Signin</button>
  </nav>
</div>

Just like in other frameworks, you can also pass a provider to the signIn function which will attempt to login directly with that provider.

The Express package runs server-side and therefore it doesn’t make sense to create a “SignIn button component”. However, to signin or signout with Express, send a request to the appropriate REST API Endpoints from your client (i.e. /auth/signin, /auth/signout, etc.).

You can also pass a provider to the signIn function which will attempt to login directly with that provider. Otherwise, when clicking this button in your application, the user will be redirected to the configured sign in page. If you did not setup a custom sign in page, the user will be redirected to the default signin page at /[basePath]/signin.

Once authenticated, the user will be redirected back to the page they started the signin from. If you want the user to be redirected somewhere else after sign in (.i.e /dashboard), you can do so by passing the target URL as redirectTo in the sign-in options.

app/components/signin-button.tsx

import { signIn } from "../../auth.ts"
 
export function SignIn() {
  return (
    <form
      action={async () => {
        "use server"
        await signIn("github", { redirectTo: "/dashboard" })
      }}
    >
      <button type="submit">Sign in</button>
    </form>
  )
}

src/components/signin-button.tsx

import { signIn } from "next-auth/react"
 
export function SignIn() {
  return (
    <Button onClick={() => signIn("github", { redirectTo: "/dashboard" })}>
      Sign In
    </Button>
  )
}

src/routes/+page.svelte

<script lang="ts">
  import { page } from "$app/stores"
  import { SignIn } from "@auth/sveltekit/components"
</script>
 
<header>
  <nav>
    <SignIn
      options={{
        redirectTo: $page.data.redirectTo
          ? `/${decodeURIComponent($page.data.redirectTo).slice(1)}`
          : `/dashboard`,
      }}
      className="w-full"
    >
      <span slot="submitButton">Sign in</span>
    </SignIn>
  </nav>
</header>

Signout

Signing out can be done similarly to signing in. Most frameworks offer both a client-side and server-side method for signing out as well.

To sign out users with a form action, you can build a button that calls the exported signout function from your Auth.js config.

app/components/signout-button.tsx

import { signOut } from "../../auth.ts"
 
export function SignOut() {
  return (
    <form
      action={async () => {
        "use server"
        await signOut()
      }}
    >
      <button type="submit">Sign Out</button>
    </form>
  )
}

Again, in a client component, you can use the next-auth/react imports as they are marked with the "use client;" directive.

./components/auth/signin-button.tsx

import { signOut } from "next-auth/react"
 
export function SignOut() {
  return <Button onClick={() => signOut()}>Signout</Button>
}

src/components/signout-button.tsx

import { signOut } from "next-auth/react"
 
export function SignOut() {
  return <button onClick={() => signOut()}>Sign Out</button>
}

SvelteKit supports both server and client-side methods for signing out as well.

Server-side

To use the SvelteKit form action for signing out, we can use the SignOut component exported from @auth/sveltekit/components.

src/routes/+page.svelte

<script lang="ts">
  import { SignOut } from "@auth/sveltekit/components"
</script>
 
<header>
  <nav>
    <SignOut>
      <span slot="submitButton">Signout</span>
    </SignIn>
  </nav>
</header>

This requires a server action at /signout, this path can be customized with the signOutPage prop on the <SignOut> component.

src/routes/signout/+page.server.ts

import { signOut } from "../../auth"
import type { Actions } from "./$types"
 
export const actions: Actions = { default: signOut }

Client Side

Client-side is a bit simpler as we just need to import a button on:click handler from @auth/sveltekit/client.

src/routes/+page.svelte

<script lang="ts">
  import { signOut } from '@auth/sveltekit/client'
</script>
 
<div>
  <nav>
    <img src="/img/logo.svg" alt="Company Logo" />
    <button on:click={signOut}>Signout</button>
  </nav>
</div>

💡

Note that when signing out of an OAuth provider like GitHub in an Auth.js application, the user will not be signed out of GitHub elsewhere.

Database Get Session

Handling Signin and Signout

Form Action (Server-Side)

Client Side

Signout

Server-side

Client Side

About Auth.js

Download

Acknowledgements