Add ActionCodeSettings.linkDomain and deprecate ActionCodeSettings.dynamicLinkDomain (#8738)

* Add linkDomain field to ActionCodeSettings (#8428) * Add linkDomain field to ActionCodeSettings * Update API reports * Update error message for ERROR_INVALID_HOSTING_LINK_DOMAIN to include that default hosting domains cannot be used. * Use constants for test values --------- Co-authored-by: NhienLam <[email protected]> * FDL Deprecation & Hosting link Integration Test (#8603) * Implement Integration test for passwordless email sign-in via firebase-hosting links. * Add license to new test file created' did not match any files * Remove unwanted _ * Add support for setting custom hosting link domain in test app (#8614) * Add afterEach method and apply formatting to the hosting links integration test (#8615) * Mark ActionCodeSettings.dynamicLinkDomain as deprecated * Add changeset * Update API reports * Address review comments * Fix changeset * Update refdocs and address review comments * Update deprecated comment * Add FDL deprecation FAQ link * Fix linkDomain link in refdocs --------- Co-authored-by: NhienLam <[email protected]> Co-authored-by: mansisampat <[email protected]>
2026-09-24 16:59:10 +00:00 · 2025-02-04 14:18:02 -08:00
parent 7bec6a1f4b
commit 0e520b0401
18 changed files with 232 additions and 37 deletions
@@ -0,0 +1,7 @@
+---
+'firebase': minor
+'@firebase/auth-types': minor
+'@firebase/auth': minor
+---
+
+Added `ActionCodeSettings.linkDomain` to customize the Firebase Hosting link domain that is used in mobile out-of-band email action flows. Also, deprecated `ActionCodeSettings.dynamicLinkDomain`.
@@ -40,11 +40,13 @@ export interface ActionCodeSettings {
        minimumVersion?: string;
        packageName: string;
    };
+    // @deprecated
    dynamicLinkDomain?: string;
    handleCodeInApp?: boolean;
    iOS?: {
        bundleId: string;
    };
+    linkDomain?: string;
    url: string;
 }

@@ -236,6 +238,7 @@ export const AuthErrorCodes: {
    readonly MISSING_RECAPTCHA_VERSION: "auth/missing-recaptcha-version";
    readonly INVALID_RECAPTCHA_VERSION: "auth/invalid-recaptcha-version";
    readonly INVALID_REQ_TYPE: "auth/invalid-req-type";
+    readonly INVALID_HOSTING_LINK_DOMAIN: "auth/invalid-hosting-link-domain";
 };

 // @public
@@ -26,13 +26,14 @@ export interface ActionCodeSettings
 |  [dynamicLinkDomain](./auth.actioncodesettings.md#actioncodesettingsdynamiclinkdomain) | string | When multiple custom dynamic link domains are defined for a project, specify which one to use when the link is to be opened via a specified mobile app (for example, <code>example.page.link</code>). |
 |  [handleCodeInApp](./auth.actioncodesettings.md#actioncodesettingshandlecodeinapp) | boolean | When set to true, the action code link will be be sent as a Universal Link or Android App Link and will be opened by the app if installed. |
 |  [iOS](./auth.actioncodesettings.md#actioncodesettingsios) | { bundleId: string; } | Sets the iOS bundle ID. |
+|  [linkDomain](./auth.actioncodesettings.md#actioncodesettingslinkdomain) | string | The optional custom Firebase Hosting domain to use when the link is to be opened via a specified mobile app. The domain must be configured in Firebase Hosting and owned by the project. This cannot be a default Hosting domain (<code>web.app</code> or <code>firebaseapp.com</code>). |
 |  [url](./auth.actioncodesettings.md#actioncodesettingsurl) | string | Sets the link continue/state URL. |

 ## ActionCodeSettings.android

 Sets the Android package name.

-This will try to open the link in an android app if it is installed. If `installApp` is passed, it specifies whether to install the Android app if the device supports it and the app is not already installed. If this field is provided without a `packageName`<!-- -->, an error is thrown explaining that the `packageName` must be provided in conjunction with this field. If `minimumVersion` is specified, and an older version of the app is installed, the user is taken to the Play Store to upgrade the app.
+This will try to open the link in an Android app if it is installed.

 <b>Signature:</b>

@@ -46,6 +47,11 @@ android?: {

 ## ActionCodeSettings.dynamicLinkDomain

+> Warning: This API is now obsolete.
+> 
+> Firebase Dynamic Links is deprecated and will be shut down as early as August 2025. Instead, use [ActionCodeSettings.linkDomain](./auth.actioncodesettings.md#actioncodesettingslinkdomain) to set a custom domain for mobile links. Learn more in the [Dynamic Links deprecation FAQ](https://firebase.google.com/support/dynamic-links-faq)<!-- -->.
+> 
+
 When multiple custom dynamic link domains are defined for a project, specify which one to use when the link is to be opened via a specified mobile app (for example, `example.page.link`<!-- -->).

 <b>Signature:</b>
@@ -72,8 +78,6 @@ Sets the iOS bundle ID.

 This will try to open the link in an iOS app if it is installed.

-App installation is not supported for iOS.
-
 <b>Signature:</b>

 ```typescript
@@ -82,11 +86,21 @@ iOS?: {
    };
 ```

+## ActionCodeSettings.linkDomain
+
+The optional custom Firebase Hosting domain to use when the link is to be opened via a specified mobile app. The domain must be configured in Firebase Hosting and owned by the project. This cannot be a default Hosting domain (`web.app` or `firebaseapp.com`<!-- -->).
+
+<b>Signature:</b>
+
+```typescript
+linkDomain?: string;
+```
+
 ## ActionCodeSettings.url

 Sets the link continue/state URL.

-This has different meanings in different contexts: - When the link is handled in the web action widgets, this is the deep link in the `continueUrl` query parameter. - When the link is handled in the app directly, this is the `continueUrl` query parameter in the deep link of the Dynamic Link.
+This has different meanings in different contexts: - When the link is handled in the web action widgets, this is the deep link in the `continueUrl` query parameter. - When the link is handled in the app directly, this is the `continueUrl` query parameter in the deep link of the Dynamic Link or Hosting link.

 <b>Signature:</b>

@@ -1956,6 +1956,7 @@ AUTH_ERROR_CODES_MAP_DO_NOT_USE_INTERNALLY: {
    readonly MISSING_RECAPTCHA_VERSION: "auth/missing-recaptcha-version";
    readonly INVALID_RECAPTCHA_VERSION: "auth/invalid-recaptcha-version";
    readonly INVALID_REQ_TYPE: "auth/invalid-req-type";
+    readonly INVALID_HOSTING_LINK_DOMAIN: "auth/invalid-hosting-link-domain";
 }
 ```

@@ -130,6 +130,7 @@ export type ActionCodeSettings = {
  iOS?: { bundleId: string };
  url: string;
  dynamicLinkDomain?: string;
+  linkDomain?: string;
 };

 export type AdditionalUserInfo = {
@@ -823,6 +823,11 @@
                  <input type="text" class="form-control" id="ibi" placeholder="iOS Bundle ID"/>
                </div>
              </form>
+              <div class="group">Mobile link</div>
+              <div class="form-group">
+                <input type="text" class="form-control" id="hostingLinkDomain"
+                       placeholder="Custom Hosting Link Domain"/>
+              </div>
              <form class="form form-bordered no-submit">
                <div class="btn-group radio-block" id="handle-in-app-selection"
                     data-toggle="buttons">
@@ -49,8 +49,8 @@ import {
  signInWithCredential,
  signInWithCustomToken,
  signInWithEmailAndPassword,
+  signInWithEmailLink,
  TotpMultiFactorGenerator,
-  TotpSecret,
  unlink,
  updateEmail,
  updatePassword,
@@ -995,6 +995,7 @@ function getActionCodeSettings() {
  const installApp = $('input[name=install-app]:checked').val() === 'Yes';
  const handleCodeInApp =
    $('input[name=handle-in-app]:checked').val() === 'Yes';
+  const hostingLinkDomain = $('#hostingLinkDomain').val();
  if (url || apn || ibi) {
    actionCodeSettings['url'] = url;
    if (apn) {
@@ -1010,6 +1011,9 @@ function getActionCodeSettings() {
      };
    }
    actionCodeSettings['handleCodeInApp'] = handleCodeInApp;
+    if (hostingLinkDomain) {
+      actionCodeSettings['linkDomain'] = hostingLinkDomain;
+    }
  }
  return actionCodeSettings;
 }
@@ -1020,6 +1024,7 @@ function onActionCodeSettingsReset() {
  $('#apn').val('');
  $('#amv').val('');
  $('#ibi').val('');
+  $('#hostingLinkDomain').val('');
 }

 /**
@@ -41,7 +41,8 @@ function getTestFiles(argv) {
      return [
        'test/integration/flows/totp.test.ts',
        'test/integration/flows/password_policy.test.ts',
-        'test/integration/flows/recaptcha_enterprise.test.ts'
+        'test/integration/flows/recaptcha_enterprise.test.ts',
+        'test/integration/flows/hosting_link.test.ts'
      ];
    }
    return argv.local
@@ -70,6 +70,7 @@ export interface GetOobCodeRequest {
  dynamicLinkDomain?: string;
  tenantId?: string;
  targetProjectid?: string;
+  linkDomain?: string;
 }

 export interface VerifyEmailRequest extends GetOobCodeRequest {
@@ -100,7 +100,8 @@ export const enum ServerError {
  MISSING_RECAPTCHA_VERSION = 'MISSING_RECAPTCHA_VERSION',
  INVALID_RECAPTCHA_VERSION = 'INVALID_RECAPTCHA_VERSION',
  INVALID_REQ_TYPE = 'INVALID_REQ_TYPE',
-  PASSWORD_DOES_NOT_MEET_REQUIREMENTS = 'PASSWORD_DOES_NOT_MEET_REQUIREMENTS'
+  PASSWORD_DOES_NOT_MEET_REQUIREMENTS = 'PASSWORD_DOES_NOT_MEET_REQUIREMENTS',
+  INVALID_HOSTING_LINK_DOMAIN = 'INVALID_HOSTING_LINK_DOMAIN'
 }

 /**
@@ -134,7 +134,8 @@ export const enum AuthErrorCode {
  INVALID_RECAPTCHA_VERSION = 'invalid-recaptcha-version',
  INVALID_REQ_TYPE = 'invalid-req-type',
  UNSUPPORTED_PASSWORD_POLICY_SCHEMA_VERSION = 'unsupported-password-policy-schema-version',
-  PASSWORD_DOES_NOT_MEET_REQUIREMENTS = 'password-does-not-meet-requirements'
+  PASSWORD_DOES_NOT_MEET_REQUIREMENTS = 'password-does-not-meet-requirements',
+  INVALID_HOSTING_LINK_DOMAIN = 'invalid-hosting-link-domain'
 }

 function _debugErrorMap(): ErrorMap<AuthErrorCode> {
@@ -387,7 +388,10 @@ function _debugErrorMap(): ErrorMap<AuthErrorCode> {
    [AuthErrorCode.UNSUPPORTED_PASSWORD_POLICY_SCHEMA_VERSION]:
      'The password policy received from the backend uses a schema version that is not supported by this version of the Firebase SDK.',
    [AuthErrorCode.PASSWORD_DOES_NOT_MEET_REQUIREMENTS]:
-      'The password does not meet the requirements.'
+      'The password does not meet the requirements.',
+    [AuthErrorCode.INVALID_HOSTING_LINK_DOMAIN]:
+      'The provided Hosting link domain is not configured in Firebase Hosting or is not owned by ' +
+      'the current project. This cannot be a default Hosting domain (`web.app` or `firebaseapp.com`).'
  };
 }

@@ -598,5 +602,6 @@ export const AUTH_ERROR_CODES_MAP_DO_NOT_USE_INTERNALLY = {
  MISSING_CLIENT_TYPE: 'auth/missing-client-type',
  MISSING_RECAPTCHA_VERSION: 'auth/missing-recaptcha-version',
  INVALID_RECAPTCHA_VERSION: 'auth/invalid-recaptcha-version',
-  INVALID_REQ_TYPE: 'auth/invalid-req-type'
+  INVALID_REQ_TYPE: 'auth/invalid-req-type',
+  INVALID_HOSTING_LINK_DOMAIN: 'auth/invalid-hosting-link-domain'
 } as const;
@@ -26,6 +26,10 @@ describe('core/strategies/action_code_settings', () => {
  let auth: TestAuth;
  const request: GetOobCodeRequest = {};

+  const TEST_BUNDLE_ID = 'my-bundle';
+  const TEST_FDL_DOMAIN = 'fdl-domain';
+  const TEST_URL = 'my-url';
+
  beforeEach(async () => {
    auth = await testAuth();
  });
@@ -35,10 +39,10 @@ describe('core/strategies/action_code_settings', () => {
      _setActionCodeSettingsOnRequest(auth, request, {
        handleCodeInApp: true,
        iOS: {
-          bundleId: 'my-bundle'
+          bundleId: TEST_BUNDLE_ID
        },
        url: '',
-        dynamicLinkDomain: 'fdl-domain'
+        dynamicLinkDomain: TEST_FDL_DOMAIN
      })
    ).to.throw(FirebaseError, '(auth/invalid-continue-uri)');
  });
@@ -48,9 +52,9 @@ describe('core/strategies/action_code_settings', () => {
      _setActionCodeSettingsOnRequest(auth, request, {
        handleCodeInApp: true,
        iOS: {
-          bundleId: 'my-´bundle'
+          bundleId: TEST_BUNDLE_ID
        },
-        url: 'my-url'
+        url: TEST_URL
      })
    ).to.not.throw();
  });
@@ -60,14 +64,27 @@ describe('core/strategies/action_code_settings', () => {
      _setActionCodeSettingsOnRequest(auth, request, {
        handleCodeInApp: true,
        iOS: {
-          bundleId: 'my-´bundle'
+          bundleId: TEST_BUNDLE_ID
        },
-        url: 'my-url',
+        url: TEST_URL,
        dynamicLinkDomain: ''
      })
    ).to.throw(FirebaseError, '(auth/invalid-dynamic-link-domain)');
  });

+  it('should require a non empty Hosting link URL', () => {
+    expect(() =>
+      _setActionCodeSettingsOnRequest(auth, request, {
+        handleCodeInApp: true,
+        iOS: {
+          bundleId: TEST_BUNDLE_ID
+        },
+        url: TEST_URL,
+        linkDomain: ''
+      })
+    ).to.throw(FirebaseError, '(auth/invalid-hosting-link-domain)');
+  });
+
  it('should require a non-empty bundle ID', () => {
    expect(() =>
      _setActionCodeSettingsOnRequest(auth, request, {
@@ -75,8 +92,8 @@ describe('core/strategies/action_code_settings', () => {
        iOS: {
          bundleId: ''
        },
-        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        url: TEST_URL,
+        dynamicLinkDomain: TEST_FDL_DOMAIN
      })
    ).to.throw(FirebaseError, '(auth/missing-ios-bundle-id)');
  });
@@ -88,8 +105,8 @@ describe('core/strategies/action_code_settings', () => {
        android: {
          packageName: ''
        },
-        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        url: TEST_URL,
+        dynamicLinkDomain: TEST_FDL_DOMAIN
      })
    ).to.throw(FirebaseError, '(auth/missing-android-pkg-name)');
  });
@@ -37,9 +37,16 @@ export function _setActionCodeSettingsOnRequest(
    auth,
    AuthErrorCode.INVALID_DYNAMIC_LINK_DOMAIN
  );
+  _assert(
+    typeof actionCodeSettings.linkDomain === 'undefined' ||
+      actionCodeSettings.linkDomain.length > 0,
+    auth,
+    AuthErrorCode.INVALID_HOSTING_LINK_DOMAIN
+  );

  request.continueUrl = actionCodeSettings.url;
  request.dynamicLinkDomain = actionCodeSettings.dynamicLinkDomain;
+  request.linkDomain = actionCodeSettings.linkDomain;
  request.canHandleCodeInApp = actionCodeSettings.handleCodeInApp;

  if (actionCodeSettings.iOS) {
@@ -162,7 +162,8 @@ describe('core/strategies/sendEmailVerification', () => {
          bundleId: 'my-bundle'
        },
        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain'
      });

      expect(mock.calls[0].request).to.eql({
@@ -170,6 +171,7 @@ describe('core/strategies/sendEmailVerification', () => {
        idToken,
        continueUrl: 'my-url',
        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain',
        canHandleCodeInApp: true,
        iOSBundleId: 'my-bundle'
      });
@@ -190,13 +192,15 @@ describe('core/strategies/sendEmailVerification', () => {
          packageName: 'my-package'
        },
        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain'
      });
      expect(mock.calls[0].request).to.eql({
        requestType: ActionCodeOperation.VERIFY_EMAIL,
        idToken,
        continueUrl: 'my-url',
        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain',
        canHandleCodeInApp: true,
        androidInstallApp: false,
        androidMinimumVersionCode: 'my-version',
@@ -270,7 +274,8 @@ describe('core/strategies/verifyBeforeUpdateEmail', () => {
          bundleId: 'my-bundle'
        },
        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain'
      });

      expect(mock.calls[0].request).to.eql({
@@ -279,6 +284,7 @@ describe('core/strategies/verifyBeforeUpdateEmail', () => {
        newEmail,
        continueUrl: 'my-url',
        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain',
        canHandleCodeInApp: true,
        iOSBundleId: 'my-bundle'
      });
@@ -299,7 +305,8 @@ describe('core/strategies/verifyBeforeUpdateEmail', () => {
          packageName: 'my-package'
        },
        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain'
      });
      expect(mock.calls[0].request).to.eql({
        requestType: ActionCodeOperation.VERIFY_AND_CHANGE_EMAIL,
@@ -307,6 +314,7 @@ describe('core/strategies/verifyBeforeUpdateEmail', () => {
        newEmail,
        continueUrl: 'my-url',
        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain',
        canHandleCodeInApp: true,
        androidInstallApp: false,
        androidMinimumVersionCode: 'my-version',
@@ -121,7 +121,8 @@ describe('core/strategies/sendPasswordResetEmail', () => {
          bundleId: 'my-bundle'
        },
        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain'
      });

      expect(mock.calls[0].request).to.eql({
@@ -129,6 +130,7 @@ describe('core/strategies/sendPasswordResetEmail', () => {
        email,
        continueUrl: 'my-url',
        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain',
        canHandleCodeInApp: true,
        iOSBundleId: 'my-bundle',
        clientType: 'CLIENT_TYPE_WEB'
@@ -149,13 +151,15 @@ describe('core/strategies/sendPasswordResetEmail', () => {
          packageName: 'my-package'
        },
        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain'
      });
      expect(mock.calls[0].request).to.eql({
        requestType: ActionCodeOperation.PASSWORD_RESET,
        email,
        continueUrl: 'my-url',
        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain',
        canHandleCodeInApp: true,
        androidInstallApp: false,
        androidMinimumVersionCode: 'my-version',
@@ -124,7 +124,8 @@ describe('core/strategies/sendSignInLinkToEmail', () => {
          bundleId: 'my-bundle'
        },
        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain'
      });

      expect(mock.calls[0].request).to.eql({
@@ -132,6 +133,7 @@ describe('core/strategies/sendSignInLinkToEmail', () => {
        email,
        continueUrl: 'my-url',
        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain',
        canHandleCodeInApp: true,
        iOSBundleId: 'my-bundle',
        clientType: 'CLIENT_TYPE_WEB'
@@ -152,13 +154,15 @@ describe('core/strategies/sendSignInLinkToEmail', () => {
          packageName: 'my-package'
        },
        url: 'my-url',
-        dynamicLinkDomain: 'fdl-domain'
+        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain'
      });
      expect(mock.calls[0].request).to.eql({
        requestType: ActionCodeOperation.EMAIL_SIGNIN,
        email,
        continueUrl: 'my-url',
        dynamicLinkDomain: 'fdl-domain',
+        linkDomain: 'hosting-link-domain',
        canHandleCodeInApp: true,
        androidInstallApp: false,
        androidMinimumVersionCode: 'my-version',
@@ -462,12 +462,7 @@ export interface ActionCodeSettings {
   * Sets the Android package name.
   *
   * @remarks
-   * This will try to open the link in an android app if it is
-   * installed. If `installApp` is passed, it specifies whether to install the Android app if the
-   * device supports it and the app is not already installed. If this field is provided without
-   * a `packageName`, an error is thrown explaining that the `packageName` must be provided in
-   * conjunction with this field. If `minimumVersion` is specified, and an older version of the
-   * app is installed, the user is taken to the Play Store to upgrade the app.
+   * This will try to open the link in an Android app if it is installed.
   */
  android?: {
    installApp?: boolean;
@@ -490,8 +485,6 @@ export interface ActionCodeSettings {
   *
   * @remarks
   * This will try to open the link in an iOS app if it is installed.
-   *
-   * App installation is not supported for iOS.
   */
  iOS?: {
    bundleId: string;
@@ -504,7 +497,7 @@ export interface ActionCodeSettings {
   * - When the link is handled in the web action widgets, this is the deep link in the
   * `continueUrl` query parameter.
   * - When the link is handled in the app directly, this is the `continueUrl` query parameter in
-   * the deep link of the Dynamic Link.
+   * the deep link of the Dynamic Link or Hosting link.
   */
  url: string;
  /**
@@ -513,8 +506,20 @@ export interface ActionCodeSettings {
   *
   *
   * @defaultValue The first domain is automatically selected.
+   *
+   * @deprecated Firebase Dynamic Links is deprecated and will be shut down as early as August
+   * 2025. Instead, use {@link ActionCodeSettings.linkDomain} to set a custom domain for mobile
+   * links. Learn more in the {@link https://firebase.google.com/support/dynamic-links-faq | Dynamic Links deprecation FAQ}.
   */
  dynamicLinkDomain?: string;
+  /**
+   * The optional custom Firebase Hosting domain to use when the link is to be opened via
+   * a specified mobile app. The domain must be configured in Firebase Hosting and owned
+   * by the project. This cannot be a default Hosting domain (`web.app` or `firebaseapp.com`).
+   *
+   * @defaultValue The default Hosting domain will be used (for example, `example.firebaseapp.com`).
+   */
+  linkDomain?: string;
 }

 /**
@@ -0,0 +1,106 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// eslint-disable-next-line import/no-extraneous-dependencies
+import {
+  ActionCodeSettings,
+  Auth,
+  sendSignInLinkToEmail
+} from '@firebase/auth';
+import { expect, use } from 'chai';
+import {
+  cleanUpTestInstance,
+  getTestInstance,
+  randomEmail
+} from '../../helpers/integration/helpers';
+import { getEmulatorUrl } from '../../helpers/integration/settings';
+import chaiAsPromised from 'chai-as-promised';
+import { FirebaseError } from '@firebase/util';
+
+use(chaiAsPromised);
+
+// Assumes mobileLinksConfig.domain is set as "HOSTING_DOMAIN" in the test GCP-project.
+describe('Integration test: hosting link validation', () => {
+  let auth: Auth;
+  let email: string;
+
+  const AUTHORIZED_CUSTOM_DOMAIN = 'localhost/action_code_return';
+  const ANDROID_PACKAGE_NAME = 'com.google.firebase.test.thin';
+  const BASE_SETTINGS: ActionCodeSettings = {
+    url: 'http://' + AUTHORIZED_CUSTOM_DOMAIN,
+    handleCodeInApp: true,
+    android: { packageName: ANDROID_PACKAGE_NAME }
+  };
+  const VALID_LINK_DOMAIN = 'jscore-sandbox.testdomaindonotuse.com';
+  const INVALID_LINK_DOMAIN = 'invalid.testdomaindonotuse.com';
+  const INVALID_LINK_DOMAIN_ERROR = 'auth/invalid-hosting-link-domain';
+  const TEST_TENANT_ID = 'passpol-tenant-d7hha';
+
+  beforeEach(function () {
+    auth = getTestInstance();
+    email = randomEmail();
+
+    if (getEmulatorUrl()) {
+      this.skip();
+    }
+  });
+
+  afterEach(async () => {
+    await cleanUpTestInstance(auth);
+  });
+
+  it('allows user to sign in with default firebase hosting link', async () => {
+    // Sends email link to user using default hosting link.
+    await sendSignInLinkToEmail(auth, email, BASE_SETTINGS);
+  });
+
+  it('allows user to sign in to a tenant with default firebase hosting link', async () => {
+    auth.tenantId = TEST_TENANT_ID;
+    // Sends email link to user using default hosting link.
+    await sendSignInLinkToEmail(auth, email, BASE_SETTINGS);
+  });
+
+  it('allows user to sign in with custom firebase hosting link', async () => {
+    // Sends email link to user using custom hosting link.
+    await sendSignInLinkToEmail(auth, email, {
+      ...BASE_SETTINGS,
+      linkDomain: VALID_LINK_DOMAIN
+    });
+  });
+
+  it('allows user to sign in to a tenant with custom firebase hosting link', async () => {
+    // Sends email link to user using custom hosting link.
+    auth.tenantId = TEST_TENANT_ID;
+    await sendSignInLinkToEmail(auth, email, {
+      ...BASE_SETTINGS,
+      linkDomain: VALID_LINK_DOMAIN
+    });
+  });
+
+  it('sign in with invalid firebase hosting link throws exception', async () => {
+    // Throws an exception while sening email link to user using invalid hosting link.
+    await expect(
+      sendSignInLinkToEmail(auth, email, {
+        ...BASE_SETTINGS,
+        linkDomain: INVALID_LINK_DOMAIN
+      })
+    ).to.be.rejectedWith(
+      FirebaseError,
+      new RegExp('.*' + INVALID_LINK_DOMAIN_ERROR + '.*')
+    );
+  });
+});