What is openid-client?
The openid-client package is a server-side library that allows Node.js applications to act as a Relying Party (RP) for any OpenID Connect (OIDC) compliant Identity Provider (IP). It provides functionality to discover OIDC providers, authenticate users, validate ID tokens, and securely perform token operations.
What are openid-client's main functionalities?
Discovery of OpenID Provider configuration
This feature allows the client to automatically discover the OpenID Provider's configuration using the issuer's URL. It simplifies the process of setting up the client by fetching the necessary endpoints and public keys.
const { Issuer } = require('openid-client');
(async () => {
const googleIssuer = await Issuer.discover('https://accounts.google.com');
console.log('Discovered issuer %s', googleIssuer.issuer);
})();
Client authentication with an OpenID Provider
This code sample demonstrates how to authenticate with an OpenID Provider by creating a client instance with the necessary credentials and generating an authorization URL for user redirection.
const { Issuer } = require('openid-client');
(async () => {
const issuer = await Issuer.discover('https://example.com');
const client = new issuer.Client({
client_id: 'your-client-id',
client_secret: 'your-client-secret',
redirect_uris: ['https://your-callback-url/callback'],
response_types: ['code']
});
const authorizationUrl = client.authorizationUrl({
scope: 'openid email profile',
});
console.log('Authorization URL:', authorizationUrl);
})();
Handling authentication responses
This feature is used to handle the callback from the OpenID Provider after user authentication. It involves parsing the callback parameters, exchanging the authorization code for tokens, and validating the ID token.
const { Issuer, generators } = require('openid-client');
(async () => {
const issuer = await Issuer.discover('https://example.com');
const client = new issuer.Client({
client_id: 'your-client-id',
client_secret: 'your-client-secret',
redirect_uris: ['https://your-callback-url/callback'],
response_types: ['code']
});
const code_verifier = generators.codeVerifier();
const code_challenge = generators.codeChallenge(code_verifier);
const params = client.callbackParams('https://your-callback-url/callback?code=AUTH_CODE&state=STATE');
const tokenSet = await client.callback('https://your-callback-url/callback', params, { code_verifier });
console.log('Received and validated tokens %j', tokenSet);
console.log('ID Token claims %j', tokenSet.claims());
})();
Token management
This code sample shows how to manage tokens, including how to exchange an authorization code for tokens and how to refresh tokens using a refresh token.
const { Issuer } = require('openid-client');
(async () => {
const issuer = await Issuer.discover('https://example.com');
const client = new issuer.Client({
client_id: 'your-client-id',
client_secret: 'your-client-secret'
});
const tokenSet = await client.grant({
grant_type: 'authorization_code',
code: 'AUTH_CODE',
redirect_uri: 'https://your-callback-url/callback'
});
const refreshedTokenSet = await client.refresh(tokenSet.refresh_token);
console.log('Refreshed tokens %j', refreshedTokenSet);
})();
Other packages similar to openid-client
passport
Passport is a widely used authentication middleware for Node.js. It supports a wide range of strategies, including OpenID Connect. Compared to openid-client, Passport provides a more general authentication solution that can be extended with various strategies for different authentication mechanisms.
oidc-provider
oidc-provider is a Node.js library that allows developers to implement their own OpenID Connect Provider. It is different from openid-client, which is designed to be used as a client for existing providers. oidc-provider is more suitable for those who want to create an identity provider rather than connect to one.
openid-client
openid-client is a server side OpenID Relying Party (RP, Client) implementation for
Node.js runtime, supports passport.
Implemented specs & features
The following client/RP features from OpenID Connect/OAuth2.0 specifications are implemented by
openid-client.
Updates to draft specifications are released as MINOR library versions,
if you utilize these specification implementations consider using the tilde ~
operator in your
package.json since breaking changes may be introduced as part of these version updates.
Certification
Filip Skokan has certified that openid-client
conforms to the following profiles of the OpenID Connect™ protocol
- Basic, Implicit, Hybrid, Config, Dynamic, and Form Post RP
- FAPI 1.0 Advanced RP
If you want to quickly add OpenID Connect authentication to Node.js apps, feel free to check out Auth0's Node.js SDK and free plan. Create an Auth0 account; it's free!
Support
If you or your business use openid-client, please consider becoming a sponsor so I can continue maintaining it and adding new features carefree.
Documentation
The library exposes what are essentially steps necessary to be done by a relying party consuming
OpenID Connect Authorization Server responses or wrappers around requests to its endpoints. Aside
from a generic OpenID Connect passport strategy it does not expose any framework
specific middlewares. Those can however be built using the exposed API, one such example is express-openid-connect
Install
Node.js LTS releases Codename Erbium and newer LTS releases are supported.
npm install openid-client
Note: Other javascript runtimes are not supported.
I recommend panva/oauth4webapi, or a derivate thereof, if you're
looking for a similarly compliant and certified client software that's not dependent
on the Node.js runtime builtins.
Quick start
Discover an Issuer configuration using its published .well-known endpoints
import { Issuer } from 'openid-client';
const googleIssuer = await Issuer.discover('https://accounts.google.com');
console.log('Discovered issuer %s %O', googleIssuer.issuer, googleIssuer.metadata);
Authorization Code Flow
Authorization Code flow is for obtaining Access Tokens (and optionally Refresh Tokens) to use with
third party APIs securely as well as Refresh Tokens. In this quick start your application also uses
PKCE instead of state
parameter for CSRF protection.
Create a Client instance for that issuer's authorization server intended for Authorization Code
flow.
See the documentation for full API details.
const client = new googleIssuer.Client({
client_id: 'zELcpfANLqY7Oqas',
client_secret: 'TQV5U29k1gHibH5bx1layBo0OSAvAbRT3UYW3EWrSYBB5swxjVfWUa1BS8lqzxG/0v9wruMcrGadany3',
redirect_uris: ['http://localhost:3000/cb'],
response_types: ['code'],
});
When you want to have your end-users authorize you need to send them to the issuer's
authorization_endpoint
. Consult the web framework of your choice on how to redirect but here's how
to get the authorization endpoint's URL with parameters already encoded in the query to redirect
to.
import { generators } from 'openid-client';
const code_verifier = generators.codeVerifier();
const code_challenge = generators.codeChallenge(code_verifier);
client.authorizationUrl({
scope: 'openid email profile',
resource: 'https://my.api.example.com/resource/32178',
code_challenge,
code_challenge_method: 'S256',
});
When end-users are redirected back to your redirect_uri
your application consumes the callback and
passes in the code_verifier
to include it in the authorization code grant token exchange.
const params = client.callbackParams(req);
const tokenSet = await client.callback('https://client.example.com/callback', params, { code_verifier });
console.log('received and validated tokens %j', tokenSet);
console.log('validated ID Token claims %j', tokenSet.claims());
You can then call the userinfo_endpoint
.
const userinfo = await client.userinfo(access_token);
console.log('userinfo %j', userinfo);
And later refresh the tokenSet if it had a refresh_token
.
const tokenSet = await client.refresh(refresh_token);
console.log('refreshed and validated tokens %j', tokenSet);
console.log('refreshed ID Token claims %j', tokenSet.claims());
Implicit ID Token Flow
Implicit response_type=id_token
flow is perfect for simply authenticating your end-users, assuming
the only job you want done is authenticating the user and then relying on your own session mechanism
with no need for accessing any third party APIs with an Access Token from the Authorization Server.
Create a Client instance for that issuer's authorization server intended for ID Token implicit flow.
See the documentation for full API details.
const client = new googleIssuer.Client({
client_id: 'zELcpfANLqY7Oqas',
redirect_uris: ['http://localhost:3000/cb'],
response_types: ['id_token'],
});
When you want to have your end-users authorize you need to send them to the issuer's
authorization_endpoint
. Consult the web framework of your choice on how to redirect but here's how
to get the authorization endpoint's URL with parameters already encoded in the query to redirect
to.
import { generators } from 'openid-client';
const nonce = generators.nonce();
client.authorizationUrl({
scope: 'openid email profile',
response_mode: 'form_post',
nonce,
});
When end-users hit back your redirect_uri
with a POST (authorization request included form_post
response mode) your application consumes the callback and passes the nonce
in to include it in the
ID Token verification steps.
const params = client.callbackParams(req);
const tokenSet = await client.callback('https://client.example.com/callback', params, { nonce });
console.log('received and validated tokens %j', tokenSet);
console.log('validated ID Token claims %j', tokenSet.claims());
Device Authorization Grant (Device Flow)
RFC8628 - OAuth 2.0 Device Authorization Grant (Device Flow)
is started by starting a Device Authorization Request.
const handle = await client.deviceAuthorization();
console.log('User Code: ', handle.user_code);
console.log('Verification URI: ', handle.verification_uri);
console.log('Verification URI (complete): ', handle.verification_uri_complete);
The handle represents a Device Authorization Response with the verification_uri
, user_code
and
other defined response properties.
You will display the instructions to the end-user and have him directed at verification_uri
or
verification_uri_complete
, afterwards you can start polling for the Device Access Token Response.
const tokenSet = await handle.poll();
console.log('received tokens %j', tokenSet);
This will poll in the defined interval and only resolve with a TokenSet once one is received. This
will handle the defined authorization_pending
and slow_down
"soft" errors and continue polling
but upon any other error it will reject. With tokenSet received you can throw away the handle.
FAQ
Semver?
Yes. Everything that's either exported in the TypeScript definitions file or
documented is subject to
Semantic Versioning 2.0.0. The rest is to be considered
private API and is subject to change between any versions.
How do I use it outside of Node.js
It is only built for Node.js. Other javascript runtimes are not supported.
I recommend panva/oauth4webapi, or a derivate thereof, if you're
looking for a similarly compliant and certified client software that's not dependent
on the Node.js runtime builtins.
How to make the client send client_id and client_secret in the body?
See Client Authentication Methods (docs).
Can I adjust the HTTP timeout?
See Customizing (docs).