Authenticate Using OpenID Connect in web apps

If you've upgraded to Firebase Authentication with Identity Platform, you can authenticate your users with Firebase using the OpenID Connect (OIDC) compliant provider of your choice. This makes it possible to use identity providers not natively supported by Firebase.

Before you begin

To sign in users using an OIDC provider, you must first collect some information from the provider:

Client ID: A string unique to the provider that identifies your app. Your provider might assign you a different client ID for each platform you support. This is one of the values of the aud claim in ID tokens issued by your provider.
Client secret: A secret string that the provider uses to confirm ownership of a client ID. For every client ID, you will need a matching client secret. (This value is required only if you're using the auth code flow, which is strongly recommended.)
Issuer: A string that identifies your provider. This value must be a URL that, when appended with /.well-known/openid-configuration, is the location of the provider's OIDC discovery document. For example, if the issuer is https://auth.example.com, the discovery document must be available at https://auth.example.com/.well-known/openid-configuration.

After you have the above information, enable OpenID Connect as a sign-in provider for your Firebase project:

Add Firebase to your JavaScript project.
If you haven't upgraded to Firebase Authentication with Identity Platform, do so. OpenID Connect authentication is only available in upgraded projects.
On the Sign-in providers page of the Firebase console, click Add new provider, and then click OpenID Connect.
Select whether you will be using the authorization code flow or the implicit grant flow.

You should use always the code flow if your provider supports it. The implicit flow is less secure and using it is strongly discouraged.
Give a name to this provider. Note the provider ID that's generated: something like oidc.example-provider. You'll need this ID when you add sign-in code to your app.
Specify your client ID and client secret, and your provider's issuer string. These values must exactly match the values your provider assigned to you.
Save your changes.

Handle the sign-in flow with the Firebase SDK

The easiest way to authenticate your users with Firebase using your OIDC provider is to handle the entire sign-in flow with the Firebase SDK.

To handle the sign-in flow with the Firebase JavaScript SDK, follow these steps:

Create an instance of an OAuthProvider using the provider ID you got in the Firebase console.

Web

import { OAuthProvider } from "firebase/auth";

const provider = new OAuthProvider('oidc.example-provider');

Web

var provider = new firebase.auth.OAuthProvider('oidc.example-provider');

Optional: Specify additional custom OAuth parameters that you want to send with the OAuth request.
Web
```
provider.setCustomParameters({
  // Target specific email with login hint.
  login_hint: 'user@example.com'
});
```
Web
```
provider.setCustomParameters({
  // Target specific email with login hint.
  login_hint: 'user@example.com'
});
```
Check with your provider for the parameters it supports. Note that you can't pass Firebase-required parameters with setCustomParameters. These parameters are client_id, response_type, redirect_uri, state, scope and response_mode.
Optional: Specify additional OAuth 2.0 scopes beyond basic profile that you want to request from the authentication provider.
Web
```
provider.addScope('mail.read');
provider.addScope('calendars.read');
```
Web
```
provider.addScope('mail.read');
provider.addScope('calendars.read');
```
Check with your provider for the scopes it supports.

Authenticate with Firebase using the OAuth provider object.

You can either redirect the user to the provider's sign-in page or open the sign-in page in a pop-up browser window.

Redirect flow

Redirect to the provider sign-in page by calling signInWithRedirect():

Web

import { getAuth, signInWithRedirect } from "firebase/auth";

const auth = getAuth();
signInWithRedirect(auth, provider);

Web

firebase.auth().signInWithRedirect(provider);

After the user completes sign-in and returns to your app, you can obtain the sign-in result by calling getRedirectResult().

Web

import { getAuth, getRedirectResult, OAuthProvider } from "firebase/auth";

const auth = getAuth();
getRedirectResult(auth)
  .then((result) => {
    // User is signed in.
    // IdP data available in result.additionalUserInfo.profile.

    // Get the OAuth access token and ID Token
    const credential = OAuthProvider.credentialFromResult(result);
    const accessToken = credential.accessToken;
    const idToken = credential.idToken;
  })
  .catch((error) => {
    // Handle error.
  });

Web

firebase.auth().getRedirectResult()
  .then((result) => {
    // IdP data available in result.additionalUserInfo.profile.
    // ...

    /** @type {firebase.auth.OAuthCredential} */
    var credential = result.credential;

    // OAuth access and id tokens can also be retrieved:
    var accessToken = credential.accessToken;
    var idToken = credential.idToken;
  })
  .catch((error) => {
    // Handle error.
  });

Pop-up flow

Web

import { getAuth, signInWithPopup, OAuthProvider } from "firebase/auth";

const auth = getAuth();
signInWithPopup(auth, provider)
  .then((result) => {
    // User is signed in.
    // IdP data available using getAdditionalUserInfo(result)

    // Get the OAuth access token and ID Token
    const credential = OAuthProvider.credentialFromResult(result);
    const accessToken = credential.accessToken;
    const idToken = credential.idToken;
  })
  .catch((error) => {
    // Handle error.
  });

Web

firebase.auth().signInWithPopup(provider)
  .then((result) => {
    // IdP data available in result.additionalUserInfo.profile.
    // ...

    /** @type {firebase.auth.OAuthCredential} */
    var credential = result.credential;

    // OAuth access and id tokens can also be retrieved:
    var accessToken = credential.accessToken;
    var idToken = credential.idToken;
  })
  .catch((error) => {
    // Handle error.
  });

While the above examples focus on sign-in flows, you can use the same pattern to link an OIDC provider to an existing user using linkWithRedirect() and linkWithPopup(), and re-authenticate a user with reauthenticateWithRedirect() and reauthenticateWithPopup(), which can be used to retrieve fresh credentials for sensitive operations that require recent login.

Handle the sign-in flow manually

If you've already implemented the OpenID Connect sign-in flow in your app, you can use the ID token directly to authenticate with Firebase:

Web

import { getAuth, signInWithCredential, OAuthProvider } from "firebase/auth";

const provider = new OAuthProvider("oidc.example-provider");
const credential = provider.credential({
    idToken: idToken,
});
signInWithCredential(getAuth(), credential)
    .then((result) => {
        // User is signed in.
        // IdP data available in result.additionalUserInfo.profile.

        // Get the OAuth access token and ID Token
        const credential = OAuthProvider.credentialFromResult(result);
        const accessToken = credential.accessToken;
        const idToken = credential.idToken;
    })
    .catch((error) => {
        // Handle error.
    });

Web

const provider = new OAuthProvider("oidc.example-provider");
const credential = provider.credential({
    idToken: idToken,
});
firebase.auth().signInWithCredential(credential)
    .then((result) => {
        // User is signed in.
        // IdP data available in result.additionalUserInfo.profile.

        // Get the OAuth access token and ID Token
        const credential = OAuthProvider.credentialFromResult(result);
        const accessToken = credential.accessToken;
        const idToken = credential.idToken;
    })
    .catch((error) => {
        // Handle error.
    });