Add fetchSignInMethodsForEmail to auth-next (#2924)

* Add fetchSignInMethodsForEmail to auth-next

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Author: avolkovi

packages-exp/auth-exp/src/core/strategies/email.test.ts

@@ -0,0 +1,96 @@
+/**
+ * @license
+ * Copyright 2020 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.
+ */
+
+import { FirebaseError } from '@firebase/util';
+import { expect, use } from 'chai';
+import * as chaiAsPromised from 'chai-as-promised';
+import { SinonStub, stub } from 'sinon';
+import { mockEndpoint } from '../../../test/api/helper';
+import { mockAuth } from '../../../test/mock_auth';
+import * as mockFetch from '../../../test/mock_fetch';
+import { Endpoint } from '../../api';
+import { ServerError } from '../../api/errors';
+import { ProviderId } from '../providers';
+import * as location from '../util/location';
+import { fetchSignInMethodsForEmail } from './email';
+
+use(chaiAsPromised);
+
+describe('fetchSignInMethodsForEmail', () => {
+  const email = '[email protected]';
+  const expectedSignInMethods = [ProviderId.PASSWORD, ProviderId.GOOGLE];
+
+  beforeEach(mockFetch.setUp);
+  afterEach(mockFetch.tearDown);
+
+  it('should return the sign in methods', async () => {
+    const mock = mockEndpoint(Endpoint.CREATE_AUTH_URI, {
+      signinMethods: expectedSignInMethods
+    });
+    const response = await fetchSignInMethodsForEmail(mockAuth, email);
+    expect(response).to.eql(expectedSignInMethods);
+    expect(mock.calls[0].request).to.eql({
+      identifier: email,
+      continueUri: location.getCurrentUrl()
+    });
+  });
+
+  context('on non standard platforms', () => {
+    let locationStub: SinonStub;
+
+    beforeEach(() => {
+      locationStub = stub(location, 'isHttpOrHttps');
+      locationStub.callsFake(() => false);
+    });
+
+    afterEach(() => {
+      locationStub.restore();
+    });
+
+    it('should use localhost for the continueUri', async () => {
+      const mock = mockEndpoint(Endpoint.CREATE_AUTH_URI, {
+        signinMethods: expectedSignInMethods
+      });
+      const response = await fetchSignInMethodsForEmail(mockAuth, email);
+      expect(response).to.eql(expectedSignInMethods);
+      expect(mock.calls[0].request).to.eql({
+        identifier: email,
+        continueUri: 'http://localhost'
+      });
+    });
+  });
+
+  it('should surface errors', async () => {
+    const mock = mockEndpoint(
+      Endpoint.CREATE_AUTH_URI,
+      {
+        error: {
+          code: 400,
+          message: ServerError.INVALID_EMAIL
+        }
+      },
+      400
+    );
+    await expect(
+      fetchSignInMethodsForEmail(mockAuth, email)
+    ).to.be.rejectedWith(
+      FirebaseError,
+      'Firebase: The email address is badly formatted. (auth/invalid-email).'
+    );
+    expect(mock.calls.length).to.eq(1);
+  });
+});

packages-exp/auth-exp/src/core/strategies/email.ts

@@ -0,0 +1,41 @@
+/**
+ * @license
+ * Copyright 2020 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.
+ */
+
+import {
+  createAuthUri,
+  CreateAuthUriRequest
+} from '../../api/authentication/create_auth_uri';
+import { Auth } from '../../model/auth';
+import { getCurrentUrl, isHttpOrHttps } from '../util/location';
+
+export async function fetchSignInMethodsForEmail(
+  auth: Auth,
+  email: string
+): Promise<string[]> {
+  // createAuthUri returns an error if continue URI is not http or https.
+  // For environments like Cordova, Chrome extensions, native frameworks, file
+  // systems, etc, use http://localhost as continue URL.
+  const continueUri = isHttpOrHttps() ? getCurrentUrl() : 'http://localhost';
+  const request: CreateAuthUriRequest = {
+    identifier: email,
+    continueUri
+  };
+
+  const { signinMethods } = await createAuthUri(auth, request);
+
+  return signinMethods || [];
+}

packages-exp/auth-exp/src/core/util/location.ts

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+/**
+ * @license
+ * Copyright 2020 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.
+ */
+
+export function getCurrentUrl(): string {
+  return self?.location?.href || '';
+}
+
+export function isHttpOrHttps(): boolean {
+  return getCurrentScheme() === 'http:' || getCurrentScheme() === 'https:';
+}
+
+export function getCurrentScheme(): string | null {
+  return self?.location?.protocol || null;
+}