Firebase Phone Auth Testing in Flutter: Test Numbers vs Real SMS

// lib/phone_auth_service.dart import 'dart:async'; import 'package:firebase_auth/firebase_auth.dart'; import 'package:flutter/foundation.dart' show debugPrint, kIsWeb; class PhoneAuthService { PhoneAuthService([FirebaseAuth? auth]) : _auth = auth ?? FirebaseAuth.instance; final FirebaseAuth _auth; String? _verificationId; int? _resendToken; // Android only; always null on iOS ConfirmationResult? _webResult; // web only /// UserCredential: Android finished verification on its own (instant or auto-read SMS). /// null: the SMS was sent; wait for the user to type the code, then call confirm(). /// Error: the FirebaseAuthException from verificationFailed. Future<UserCredential?> start(String phoneE164, {bool resend = false}) async { if (kIsWeb) { // Without a RecaptchaVerifier, the SDK creates an invisible reCAPTCHA _webResult = await _auth.signInWithPhoneNumber(phoneE164); return null; } final done = Completer<UserCredential?>(); await _auth.verifyPhoneNumber( phoneNumber: phoneE164, // E.164 like +84...; the country code is required timeout: const Duration(seconds: 60), // default 30 seconds, max 2 minutes forceResendingToken: resend ? _resendToken : null, verificationCompleted: (PhoneAuthCredential credential) async { // Android only. It can arrive AFTER codeSent and sign the user in silently, // so the UI should listen to authStateChanges() instead of only awaiting this Future. try { final uc = await _auth.signInWithCredential(credential); if (!done.isCompleted) done.complete(uc); } on FirebaseAuthException catch (e) { if (!done.isCompleted) done.completeError(e); } }, verificationFailed: (FirebaseAuthException e) { debugPrint('verificationFailed: ${e.code}'); // the real error lives here, don't swallow it if (!done.isCompleted) done.completeError(e); }, codeSent: (String verificationId, int? resendToken) { _verificationId = verificationId; _resendToken = resendToken; if (!done.isCompleted) done.complete(null); }, codeAutoRetrievalTimeout: (String verificationId) { _verificationId = verificationId; // Android only }, ); return done.future; } Future<UserCredential> confirm(String smsCode) { if (kIsWeb) return _webResult!.confirm(smsCode); final credential = PhoneAuthProvider.credential( verificationId: _verificationId!, smsCode: smsCode, ); return _auth.signInWithCredential(credential); } } /// The docs only show 'invalid-phone-number'; the other code is a common example, /// so always keep the default branch. String phoneAuthMessage(FirebaseAuthException e) => switch (e.code) { 'invalid-phone-number' => 'Invalid phone number. Include the country code.', 'too-many-requests' => 'Too many attempts. Please wait a moment.', _ => 'Could not send the code (${e.code}). Please try again later.', }; 

// integration_test/phone_auth_test.dart // Run: flutter test integration_test/phone_auth_test.dart -d emulator-5554 \ // --dart-define-from-file=test_secrets.json (this file is in .gitignore) import 'package:firebase_auth/firebase_auth.dart'; import 'package:firebase_core/firebase_core.dart'; import 'package:flutter_test/flutter_test.dart'; import 'package:integration_test/integration_test.dart'; import 'package:my_app/firebase_options.dart'; // generated by `flutterfire configure` import 'package:my_app/phone_auth_service.dart'; // Must be const, or String.fromEnvironment isn't guaranteed to read the value const testPhone = String.fromEnvironment('TEST_PHONE'); const testCode = String.fromEnvironment('TEST_SMS_CODE'); void main() { IntegrationTestWidgetsFlutterBinding.ensureInitialized(); setUpAll(() async { await Firebase.initializeApp(options: DefaultFirebaseOptions.currentPlatform); // ONLY affects numbers listed under "Phone numbers for testing" await FirebaseAuth.instance.setSettings(appVerificationDisabledForTesting: true); }); tearDown(() => FirebaseAuth.instance.signOut()); testWidgets('signs in with a Firebase fictional number', (tester) async { expect(testPhone, isNotEmpty, reason: 'TEST_PHONE is missing from --dart-define'); expect(testCode, isNotEmpty, reason: 'TEST_SMS_CODE is missing from --dart-define'); final service = PhoneAuthService(); // Bounded, so a CI job doesn't hang if no callback ever fires final auto = await service.start(testPhone).timeout(const Duration(seconds: 90)); final uc = auto ?? await service.confirm(testCode); expect(uc.user, isNotNull); expect(FirebaseAuth.instance.currentUser?.uid, uc.user!.uid); }); } 

// integration_test/support/sms_provider.dart import 'dart:async'; import 'dart:convert'; import 'package:http/http.dart' as http; // The test runs on the phone and can't see the runner's env: values come in via --dart-define const _apiUrl = String.fromEnvironment('SMS_API_URL'); // the .../stubs/handler_api.php endpoint const _apiKey = String.fromEnvironment('SMS_API_KEY'); // CI secret, never committed class SmsProviderException implements Exception { SmsProviderException(this.code, [this.httpStatus]); final String code; // BAD_KEY, NO_NUMBERS, NO_BALANCE, EARLY_CANCEL_DENIED... final int? httpStatus; @override String toString() => 'SmsProviderException($code, HTTP ${httpStatus ?? 200})'; } class Activation { Activation(this.id, this.phone, this.cost) : rentedAt = DateTime.now(); final String id; final String phone; // +E.164 final String cost; // activationCost: add these up to see what each run costs final DateTime rentedAt; } class SmsProvider { final _http = http.Client(); Future<Object?> _call(Map<String, String> params) async { if (_apiUrl.isEmpty || _apiKey.isEmpty) { throw StateError('SMS_API_URL or SMS_API_KEY is missing'); // don't print the values } final base = Uri.parse(_apiUrl); final uri = base.replace( queryParameters: {...base.queryParameters, 'api_key': _apiKey, ...params}); final http.Response res; try { res = await _http.get(uri).timeout(const Duration(seconds: 30)); } on http.ClientException { throw SmsProviderException('NETWORK'); // the original message contains the URI, api_key included } Object? body; try { body = jsonDecode(res.body); // a JSON object or a quoted string } on FormatException { body = res.body.trim(); // plain text: STATUS_OK:123456, NO_NUMBERS... } if (res.statusCode >= 400) { // Errors are JSON {"title":"BAD_KEY","details":"..."} with HTTP 4xx/5xx final code = body is Map ? '${body['title']}' : 'HTTP_${res.statusCode}'; throw SmsProviderException(code, res.statusCode); } return body; } /// service: code from action=getServicesList; country: ID from action=getCountries Future<Activation> rentNumber({required String service, required int country}) async { final body = await _call( {'action': 'getNumberV2', 'service': service, 'country': '$country'}); if (body is! Map) throw SmsProviderException('$body'); // NO_NUMBERS: a string, HTTP 200 return Activation( '${body['activationId']}', '+${body['phoneNumber']}', '${body['activationCost']}'); } /// Polls getStatus until STATUS_OK:<code>; keeps waiting on STATUS_WAIT_*. Future<String> waitForCode(String id, {Duration timeout = const Duration(minutes: 3)}) async { final deadline = DateTime.now().add(timeout); while (DateTime.now().isBefore(deadline)) { final status = '${await _call({'action': 'getStatus', 'id': id})}'; if (status.startsWith('STATUS_OK:')) return status.substring('STATUS_OK:'.length); // STATUS_CANCEL or anything unexpected: stop now instead of polling until the timeout if (!status.startsWith('STATUS_WAIT')) throw SmsProviderException(status); await Future<void>.delayed(const Duration(seconds: 5)); } throw TimeoutException('No SMS for activation $id', timeout); } /// 6 = complete (code used), 8 = cancel and refund (code not used) Future<void> close(Activation a, {required bool used}) async { Future<Object?> setStatus(String s) => _call({'action': 'setStatus', 'id': a.id, 'status': s}); try { await setStatus(used ? '6' : '8'); } on SmsProviderException catch (e) { if (e.code == 'EARLY_CANCEL_DENIED') { // No cancel in the first 2 minutes (minActivationTime: 120): wait past that mark, then cancel final wait = a.rentedAt.add(const Duration(seconds: 125)).difference(DateTime.now()); if (!wait.isNegative) await Future<void>.delayed(wait); await setStatus('8'); } else if (e.code == 'OTP_RECEIVED') { await setStatus('6'); // the SMS arrived: close the activation as completed } else { rethrow; } } } void dispose() => _http.close(); } 

// integration_test/phone_auth_real_test.dart (real devices only) import 'package:firebase_auth/firebase_auth.dart'; import 'package:firebase_core/firebase_core.dart'; import 'package:flutter/foundation.dart' show debugPrint; import 'package:flutter_test/flutter_test.dart'; import 'package:integration_test/integration_test.dart'; import 'package:my_app/firebase_options.dart'; // points to the Firebase project used for testing import 'package:my_app/phone_auth_service.dart'; import 'support/sms_provider.dart'; const otpService = String.fromEnvironment('OTP_SERVICE'); // code from getServicesList const otpCountry = int.fromEnvironment('OTP_COUNTRY', defaultValue: -1); // ID from getCountries void main() { IntegrationTestWidgetsFlutterBinding.ensureInitialized()Source：https://dev.to/willette_samer/firebase-phone-auth-testing-in-flutter-test-numbers-vs-real-sms-59jn
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