Name:
interface
Value:
Amplify has re-imagined the way frontend developers build fullstack applications. Develop and deploy without the hassle.

Choose your framework/language

Page updated Jun 6, 2024

Nuxt.js server runtime

This guide walks through how you can connect to Amplify Data from Nuxt.js Server-side Runtime (SSR). For Nuxt.js applications, Amplify provides first-class support for Routing (Pages) , API Routes , and Middleware.

Before you begin, you will need:

Connect to Amplify Data from a Nuxt.js server runtime

Connecting to Amplify Data will include setting up the AmplifyAPIs Plugin with the runWithAmplifyServerContext adapter, using the useNuxtApp() composable, setting up the Amplify server context utility and then using the runAmplifyApi function to call the API in an isolated server context.

Step 1 - Set up the AmplifyAPIs Plugin

Nuxt 3 offers universal rendering by default, where your data fetching logic may be executed on both the client and server sides. Amplify offers APIs that are capable of running within a server context to support use cases such as server-side rendering (SSR) and static site generation (SSG), though Amplify's client-side APIs and server-side APIs of Amplify are slightly different. You can set up an AmplifyAPIs plugin to make your data fetching logic run smoothly across the client and server. To learn more about how to use Amplify categories APIs in server side rendering, refer to this documentation.

  1. Create a plugins directory under the root of your Nuxt project.
  2. Create two files 01.amplify-apis.client.ts and 01.amplify-apis.server.ts under the plugins directory.

In these files, you will register both client-specific and server-specific Amplify APIs that you will use in your Nuxt project as a plugin. You can then access these APIs via the useNuxtApp composable.

NOTE: The leading number in the files name indicate the plugin loading order, for more details see https://nuxt.com/docs/guide/directory-structure/plugins#registration-order. The .client and .server indicate the runtime that the logic contained in the file will run on, client or server. For details see: https://nuxt.com/docs/guide/directory-structure/plugins

Modify the 01.amplify-apis.client.ts file, with the following code:

Expand to view the code implementation
nuxt-amplify-gen2/plugins/01.amplify-apis.client.ts
import {
fetchAuthSession,
fetchUserAttributes,
signIn,
signOut,
getCurrentUser,
} from "aws-amplify/auth";
import { generateClient } from "aws-amplify/data";
import outputs from "../amplify_outputs.json";
import type { Schema } from "@/amplify/data/resource";
import { Amplify } from "aws-amplify";
// configure the Amplify client library
if (process.client) {
Amplify.configure(outputs, { ssr: true });
}
// generate your data client using the Schema from your backend
const client = generateClient<Schema>();
export default defineNuxtPlugin({
name: "AmplifyAPIs",
enforce: "pre",
setup() {
return {
provide: {
// You can call the API by via the composable `useNuxtApp()`. For example:
// `useNuxtApp().$Amplify.Auth.fetchAuthSession()`
Amplify: {
Auth: {
fetchAuthSession,
fetchUserAttributes,
getCurrentUser,
signIn,
signOut,
},
GraphQL: {
client,
},
},
},
};
},
});

Make sure you call Amplify.configure as early as possible in your application’s life-cycle. A missing configuration or NoCredentials error is thrown if Amplify.configure has not been called before other Amplify JavaScript APIs. Review the Library Not Configured Troubleshooting guide for possible causes of this issue.

Next, modify the 01.amplify-apis.server.ts file, with the following code:

Expand to view the code implementation
nuxt-amplify-gen2/plugins/01.amplify-apis.server.ts
import type { CookieRef } from "nuxt/app";
import {
createKeyValueStorageFromCookieStorageAdapter,
createUserPoolsTokenProvider,
createAWSCredentialsAndIdentityIdProvider,
runWithAmplifyServerContext,
} from "aws-amplify/adapter-core";
import { parseAmplifyConfig } from "aws-amplify/utils";
import {
fetchAuthSession,
fetchUserAttributes,
getCurrentUser,
} from "aws-amplify/auth/server";
import { generateClient } from "aws-amplify/data/server";
import type {
LibraryOptions,
FetchAuthSessionOptions,
} from "@aws-amplify/core";
import type {
GraphQLOptionsV6,
GraphQLResponseV6,
} from "@aws-amplify/api-graphql";
import outputs from "../amplify_outputs.json";
// parse the content of `amplify_outputs.json` into the shape of ResourceConfig
const amplifyConfig = parseAmplifyConfig(outputs);
// create the Amplify used token cookies names array
const userPoolClientId = amplifyConfig.Auth!.Cognito.userPoolClientId;
const lastAuthUserCookieName = `CognitoIdentityServiceProvider.${userPoolClientId}.LastAuthUser`;
// create a GraphQL client that can be used in a server context
const gqlServerClient = generateClient({ config: amplifyConfig });
const getAmplifyAuthKeys = (lastAuthUser: string) =>
["idToken", "accessToken", "refreshToken", "clockDrift"]
.map(
(key) =>
`CognitoIdentityServiceProvider.${userPoolClientId}.${lastAuthUser}.${key}`
)
.concat(lastAuthUserCookieName);
// define the plugin
export default defineNuxtPlugin({
name: "AmplifyAPIs",
enforce: "pre",
setup() {
// The Nuxt composable `useCookie` is capable of sending cookies to the
// client via the `SetCookie` header. If the `expires` option is left empty,
// it sets a cookie as a session cookie. If you need to persist the cookie
// on the client side after your end user closes your Web app, you need to
// specify an `expires` value.
//
// We use 30 days here as an example (the default Cognito refreshToken
// expiration time).
const expires = new Date();
expires.setDate(expires.getDate() + 30);
// Get the last auth user cookie value
//
// We use `sameSite: 'lax'` in this example, which allows the cookie to be
// sent to your Nuxt server when your end user gets redirected to your Web
// app from a different domain. You should choose an appropriate value for
// your own use cases.
const lastAuthUserCookie = useCookie(lastAuthUserCookieName, {
sameSite: "lax",
expires,
secure: true,
});
// Get all Amplify auth token cookie names
const authKeys = lastAuthUserCookie.value
? getAmplifyAuthKeys(lastAuthUserCookie.value)
: [];
// Create a key-value map of cookie name => cookie ref
//
// Using the composable `useCookie` here in the plugin setup prevents
// cross-request pollution.
const amplifyCookies = authKeys
.map((name) => ({
name,
cookieRef: useCookie(name, { sameSite: "lax", expires, secure: true }),
}))
.reduce<Record<string, CookieRef<string | null | undefined>>>(
(result, current) => ({
...result,
[current.name]: current.cookieRef,
}),
{}
);
// Create a key value storage based on the cookies
//
// This key value storage is responsible for providing Amplify Auth tokens to
// the APIs that you are calling.
//
// If you implement the `set` method, when Amplify needed to refresh the Auth
// tokens on the server side, the new tokens would be sent back to the client
// side via `SetCookie` header in the response. Otherwise the refresh tokens
// would not be propagate to the client side, and Amplify would refresh
// the tokens when needed on the client side.
//
// In addition, if you decide not to implement the `set` method, you don't
// need to pass any `CookieOptions` to the `useCookie` composable.
const keyValueStorage = createKeyValueStorageFromCookieStorageAdapter({
get(name) {
const cookieRef = amplifyCookies[name];
if (cookieRef && cookieRef.value) {
return { name, value: cookieRef.value };
}
return undefined;
},
getAll() {
return Object.entries(amplifyCookies).map(([name, cookieRef]) => {
return { name, value: cookieRef.value ?? undefined };
});
},
set(name, value) {
const cookieRef = amplifyCookies[name];
if (cookieRef) {
cookieRef.value = value;
}
},
delete(name) {
const cookieRef = amplifyCookies[name];
if (cookieRef) {
cookieRef.value = null;
}
},
});
// Create a token provider
const tokenProvider = createUserPoolsTokenProvider(
amplifyConfig.Auth!,
keyValueStorage
);
// Create a credentials provider
const credentialsProvider = createAWSCredentialsAndIdentityIdProvider(
amplifyConfig.Auth!,
keyValueStorage
);
// Create the libraryOptions object
const libraryOptions: LibraryOptions = {
Auth: {
tokenProvider,
credentialsProvider,
},
};
return {
provide: {
// You can add the Amplify APIs that you will use on the server side of
// your Nuxt app here. You must only use the APIs exported from the
// `aws-amplify/<category>/server` subpaths.
//
// You can call the API by via the composable `useNuxtApp()`. For example:
// `useNuxtApp().$Amplify.Auth.fetchAuthSession()`
//
// Recall that Amplify server APIs are required to be called in a isolated
// server context that is created by the `runWithAmplifyServerContext`
// function.
Amplify: {
Auth: {
fetchAuthSession: (options: FetchAuthSessionOptions) =>
runWithAmplifyServerContext(
amplifyConfig,
libraryOptions,
(contextSpec) => fetchAuthSession(contextSpec, options)
),
fetchUserAttributes: () =>
runWithAmplifyServerContext(
amplifyConfig,
libraryOptions,
(contextSpec) => fetchUserAttributes(contextSpec)
),
getCurrentUser: () =>
runWithAmplifyServerContext(
amplifyConfig,
libraryOptions,
(contextSpec) => getCurrentUser(contextSpec)
),
},
GraphQL: {
client: {
// Follow this typing to ensure the`graphql` API return type can
// be inferred correctly according to your queries and mutations
graphql: <
FALLBACK_TYPES = unknown,
TYPED_GQL_STRING extends string = string
>(
options: GraphQLOptionsV6<FALLBACK_TYPES, TYPED_GQL_STRING>,
additionalHeaders?: Record<string, string>
) =>
runWithAmplifyServerContext<
GraphQLResponseV6<FALLBACK_TYPES, TYPED_GQL_STRING>
>(amplifyConfig, libraryOptions, (contextSpec) =>
gqlServerClient.graphql(
contextSpec,
options,
additionalHeaders
)
),
},
},
},
},
};
},
});

Step 2 - Use the useNuxtApp() composable

Using the GraphQL API in ~/app.vue:

nuxt-amplify-gen2/app.vue
<script setup lang="ts">
import { Authenticator } from '@aws-amplify/ui-vue';
import '@aws-amplify/ui-vue/styles.css';
import { onMounted, ref } from 'vue';
import type { Schema } from '@/amplify/data/resource';
// create a reactive reference to the array of todos
const todos = ref<Schema['Todo']['type'][]>([]);
async function listTodos() {
try {
// `$Amplify` is generated by Nuxt according to the `provide` key in the plugins
// fetch all todos
const { data } = await useNuxtApp().$Amplify.GraphQL.client.models.Todo.list();
todos.value = data;
} catch (error) {
console.error('Error fetching todos', error);
}
}
// fetch todos when the component is mounted
onMounted(() => {
listTodos();
});
</script>
<template>
<Authenticator>
<template v-slot="{ user, signOut }">
<h1>Hello, Amplify 👋</h1>
<ul>
<li v-for="todo in todos" :key="todo.id">{{ todo.content }}</li>
</ul>
<button @click="signOut">Sign Out</button>
</template>
</Authenticator>
</template>

The app.vue file can be rendered on both the client and server sides by default. The useNuxtApp().$Amplify composable will pick up the correct implementation of 01.amplify-apis.client.ts and 01.amplify-apis.server.ts to use, depending on the runtime.

Only a subset of Amplify APIs are usable on the server side, and as the libraries evolve, amplify-apis.client and amplify-apis.server may diverge further. You can guard your API calls to ensure an API is available in the context where you use it. E.g., you can use if (process.client) to ensure that a client-only API isn't executed on the server.

Step 3 - Set up Amplify for API Routes

Following the specification of Nuxt, your API route handlers will live under ~/server, which is a separate environment from other parts of your Nuxt app; hence, the plugins created in the previous step are not usable here, and extra work is required.

Setup Amplify Server Context Utility

  1. Create a utils directory under the server directory of your Nuxt project.
  2. Create an amplifyUtils.ts file under the utils directory.

In this file, you will create a helper function to call Amplify APIs that are capable of running on the server side with context isolation. Modify the amplifyUtils.ts file, with the following code:

Expand to view the code implementation
nuxt-amplify-gen2/server/utils/amplifyUtils.ts
import type { H3Event, EventHandlerRequest } from "h3";
import {
createKeyValueStorageFromCookieStorageAdapter,
createUserPoolsTokenProvider,
createAWSCredentialsAndIdentityIdProvider,
runWithAmplifyServerContext,
AmplifyServer,
CookieStorage,
} from "aws-amplify/adapter-core";
import { parseAmplifyConfig } from "aws-amplify/utils";
import type { LibraryOptions } from "@aws-amplify/core";
import outputs from "~/amplify_outputs.json";
const amplifyConfig = parseAmplifyConfig(outputs);
const createCookieStorageAdapter = (
event: H3Event<EventHandlerRequest>
): CookieStorage.Adapter => {
// `parseCookies`, `setCookie` and `deleteCookie` are Nuxt provided functions
const readOnlyCookies = parseCookies(event);
return {
get(name) {
if (readOnlyCookies[name]) {
return { name, value: readOnlyCookies[name] };
}
},
set(name, value, options) {
setCookie(event, name, value, options);
},
delete(name) {
deleteCookie(event, name);
},
getAll() {
return Object.entries(readOnlyCookies).map(([name, value]) => {
return { name, value };
});
},
};
};
const createLibraryOptions = (
event: H3Event<EventHandlerRequest>
): LibraryOptions => {
const cookieStorage = createCookieStorageAdapter(event);
const keyValueStorage =
createKeyValueStorageFromCookieStorageAdapter(cookieStorage);
const tokenProvider = createUserPoolsTokenProvider(
amplifyConfig.Auth!,
keyValueStorage
);
const credentialsProvider = createAWSCredentialsAndIdentityIdProvider(
amplifyConfig.Auth!,
keyValueStorage
);
return {
Auth: {
tokenProvider,
credentialsProvider,
},
};
};
export const runAmplifyApi = <Result>(
// we need the event object to create a context accordingly
event: H3Event<EventHandlerRequest>,
operation: (
contextSpec: AmplifyServer.ContextSpec
) => Result | Promise<Result>
) => {
return runWithAmplifyServerContext<Result>(
amplifyConfig,
createLibraryOptions(event),
operation
);
};

Now, you can use the runAmplifyApi function to call Amplify APIs in an isolated server context. Create a new API route /api/current-user in the server directory and modify the current-user.ts file, with the following code:

nuxt-amplify-gen2/server/api/current-user.ts
import { getCurrentUser } from "aws-amplify/auth/server";
import { runAmplifyApi } from "~/server/utils/amplifyUtils";
export default defineEventHandler(async (event) => {
const user = await runAmplifyApi(event, (contextSpec) =>
getCurrentUser(contextSpec)
);
return user;
});

You can then fetch data from this API route, for example: fetch('http://localhost:3000/api/current-user')