cognito-auth-svelte

Cognito Auth

This library provides components and methods to allow a fast implementation of AWS Cognito authentication in Svelte applications.

It's optimized to work on the frontend!

Usage

First of all, initiate the auth stores using the initAuth method at the root +layout.svelte file:

<script lang="ts">
	import { initAuth } from 'cognito-auth';

	const userPoolId = '...',
		clientId = '...';

	initAuth(userPoolId, clientId);
</script>

<slot />

Note that you can store your credentials at an .env file using VITE_ as a prefix on your variable names so they can be processed at compile time:

# .env
VITE_USERPOOL_ID="..."
VITE_CLIENT_ID="..."

<!-- +layout.svelte -->
<script lang="ts">
	import { initAuth } from 'cognito-auth';

	const userPoolId = import.meta.env.VITE_USERPOOL_ID,
		clientId = import.meta.env.VITE_CLIENT_ID;

	initAuth(userPoolId, clientId);
</script>

<slot />

source: https://vitejs.dev/guide/env-and-mode.html#env-files

Then, you can start using the library's custom components:

<script lang="ts">
	import { SignIn } from 'cognito-auth';

	// ...
</script>

<SignIn
	class="signIn"
	on:submit={handleSubmit}
	on:success={handleSuccess}
	on:error={handleError}
	on:finally={handleFinally}
	togglePassword
>
	<span slot="username">Your Username</span>
	<span slot="password">Your Password</span>
	<span slot="submit">
		{#if loading}
			loading...
		{:else}
			Sign In
		{/if}
	</span>
</SignIn>

If needed, you can also access the authStore store to retrieve specific user data, available when the user is authenticated.

Available components

Component	Usage
AuthGuard	Set at any +layout.svelte file to protect its child pages from unauthenticated users.
SignIn	Lets users sign into your Cognito Userpool.
SignUp	Lets users sign up to your Cognito Userpool.
ConfirmSignUp	Used to send confirmation codes. Requires a username!
ResetPassword	Allows users to change their password when required to. Use when users are created via Admin API.
ChangePassword	Allows users to change their password when authenticated. If prompted by Cognito, prefer ResetPassword.
SignOut	Signs users out of your Cognito Userpool.

Some of those components emit custom events:

Component	Submit	Success	Error	Finally	Other
AuthGuard	❌	✅	✅	✅	❌
SignIn	✅	✅	✅	✅	passwordReset
SignUp	✅	✅	✅	✅	❌
ConfirmSignUp	✅	✅	✅	✅	❌
ResetPassword	✅	✅	✅	✅	❌
ChangePassword	✅	✅	✅	✅	❌
SignOut	✅	✅	✅	✅	❌

Available methods (@ authStore)

Method	Usage
signUp	$authStore.signUp(username: string, password: string, attributes?: ICognitoUserAttributeData[]))
confirmSignUp	$authStore.confirmSignUp(username: string, confirmationCode: string)
resendConfirmationCode	$authStore.resendConfirmationCode(username: string)
signIn	$authStore.signIn(username: string, password: string)
passwordResetChallenge	$authStore.passwordResetChallenge(username: string, oldPassword: string, newPassword: string)
signOut	$authStore.signOut(global = false)
getAttributes	$authStore.getAttributes()
updateAttributes	$authStore.updateAttributes(attributes: ICognitoUserAttributeData[])
changePassword	$authStore.changePassword(oldPassword: string, newPassword: string)
deleteUser	$authStore.deleteUser()

Notes

This library aims to keep things simple and provide functionality over all things.

It might provide some minimal styles using TailwindCSS classes to streamline its implementation into your application.