Set Auth Header for Authentication (#507)

Should close #499

Token is valid for one hour, we can keep refreshing the token as long as
the refresh token is not revoked. The refresh token gets revoked only if
the users account is deleted/disabled or revoked manually from the
backend. When the token is expired, Firebase Auth will automatically
prompt the user to log in when they open the app. The `getAuthHeader`
func refreshes the token only if it has expired or is empty or is about
to expire in 5 minutes.

app/lib/backend/api_requests/api/server.dart

@@ -22,7 +22,7 @@ Future<List<TranscriptSegment>> transcribe(File file) async {
   );
   request.files.add(await http.MultipartFile.fromPath('file', file.path, filename: basename(file.path)));
   request.headers.addAll({
-    'Authorization': await getAuthHeader(),
+    'authorization': await getAuthHeader(),
   });
 
   try {
@@ -42,9 +42,9 @@ Future<List<TranscriptSegment>> transcribe(File file) async {
   }
 }
 
-Future<bool> userHasSpeakerProfile(String uid) async {
+Future<bool> userHasSpeakerProfile() async {
   var response = await makeApiCall(
-    url: '${Env.apiBaseUrl}v1/speech-profile?uid=$uid',
+    url: '${Env.apiBaseUrl}v1/speech-profile?uid=${SharedPreferencesUtil().uid}',
     // url: 'https://5818-107-3-134-29.ngrok-free.app/v1/speech-profile',
     headers: {},
     method: 'GET',
@@ -55,10 +55,10 @@ Future<bool> userHasSpeakerProfile(String uid) async {
   return jsonDecode(response.body)['has_profile'] ?? false;
 }
 
-Future<List<SpeakerIdSample>> getUserSamplesState(String uid) async {
-  debugPrint('getUserSamplesState for uid: $uid');
+Future<List<SpeakerIdSample>> getUserSamplesState() async {
+  debugPrint('getUserSamplesState');
   var response = await makeApiCall(
-    url: '${Env.apiBaseUrl}samples?uid=$uid',
+    url: '${Env.apiBaseUrl}samples?uid=${SharedPreferencesUtil().uid}',
     headers: {},
     method: 'GET',
     body: '',
@@ -68,12 +68,15 @@ Future<List<SpeakerIdSample>> getUserSamplesState(String uid) async {
   return SpeakerIdSample.fromJsonList(jsonDecode(response.body));
 }
 
-Future<bool> uploadSample(File file, String uid) async {
-  debugPrint('uploadSample ${file.path} for uid: $uid');
+Future<bool> uploadSample(File file) async {
+  debugPrint('uploadSample ${file.path}');
   var request = http.MultipartRequest(
     'POST',
-    Uri.parse('${Env.apiBaseUrl}samples/upload?uid=$uid'),
+    Uri.parse('${Env.apiBaseUrl}samples/upload?uid=${SharedPreferencesUtil().uid}'),
   );
+  request.headers.addAll({
+    'authorization': await getAuthHeader(),
+  });
   request.files.add(await http.MultipartFile.fromPath('file', file.path, filename: basename(file.path)));
 
   try {
@@ -113,9 +116,9 @@ Future<void> migrateMemoriesToBackend(List<dynamic> memories) async {
   debugPrint('migrateMemoriesToBackend: ${response?.body}');
 }
 
-Future<String> downloadBackupApi(String uid) async {
+Future<String> downloadBackupApi() async {
   var response = await makeApiCall(
-    url: '${Env.apiBaseUrl}v1/backups?uid=$uid',
+    url: '${Env.apiBaseUrl}v1/backups?uid=${SharedPreferencesUtil().uid}',
     headers: {},
     method: 'GET',
     body: '',

app/lib/backend/api_requests/api/shared.dart

@@ -10,7 +10,11 @@ import 'package:instabug_http_client/instabug_http_client.dart';
 import 'package:internet_connection_checker_plus/internet_connection_checker_plus.dart';
 
 Future<String> getAuthHeader() async {
-  if (SharedPreferencesUtil().authToken == '') {
+  DateTime? expiry = DateTime.fromMillisecondsSinceEpoch(SharedPreferencesUtil().tokenExpirationTime);
+  if (SharedPreferencesUtil().authToken == '' ||
+      expiry.isBefore(DateTime.now()) ||
+      expiry.isAtSameMomentAs(DateTime.fromMillisecondsSinceEpoch(0)) ||
+      (expiry.isBefore(DateTime.now().add(const Duration(minutes: 5))) && expiry.isAfter(DateTime.now()))) {
     SharedPreferencesUtil().authToken = await getIdToken() ?? '';
   }
   if (SharedPreferencesUtil().authToken == '') {

app/lib/backend/auth.dart

@@ -105,19 +105,28 @@ Future<UserCredential> signInWithGoogle() async {
 listenAuthTokenChanges() {
   FirebaseAuth.instance.idTokenChanges().listen((User? user) async {
     // SharedPreferencesUtil().authToken = '123:/';
-    try {
-      var token = await getIdToken();
-      SharedPreferencesUtil().authToken = token ?? '';
-    } catch (e) {
-      debugPrint('Error getting token: $e');
+    if (user == null) {
+      debugPrint('User is currently signed out or the token has been revoked!');
+      SharedPreferencesUtil().authToken = '';
+    } else {
+      debugPrint('User is signed in!');
+      try {
+        SharedPreferencesUtil().authToken = await getIdToken() ?? '';
+      } catch (e) {
+        debugPrint('Failed to get token: $e');
+      }
     }
   });
 }
 
 Future<String?> getIdToken() async {
   try {
     IdTokenResult? newToken = await FirebaseAuth.instance.currentUser?.getIdTokenResult(true);
-    if (newToken?.token != null) SharedPreferencesUtil().uid = FirebaseAuth.instance.currentUser!.uid;
+    if (newToken?.token != null) {
+      SharedPreferencesUtil().uid = FirebaseAuth.instance.currentUser!.uid;
+      SharedPreferencesUtil().tokenExpirationTime = newToken?.expirationTime?.millisecondsSinceEpoch ?? 0;
+      SharedPreferencesUtil().authToken = newToken?.token ?? '';
+    }
     return newToken?.token;
   } catch (e) {
     print(e);
@@ -140,6 +149,7 @@ listenAuthStateChanges() {
     if (user == null) {
       debugPrint('User is currently signed out!');
       SharedPreferencesUtil().onboardingCompleted = false;
+      SharedPreferencesUtil().authToken = '';
     } else {
       debugPrint('User is signed in!');
     }

app/lib/backend/preferences.dart

@@ -260,6 +260,10 @@ class SharedPreferencesUtil {
 
   set authToken(String value) => saveString('authToken', value);
 
+  int get tokenExpirationTime => getInt('tokenExpirationTime') ?? 0;
+
+  set tokenExpirationTime(int value) => saveInt('tokenExpirationTime', value);
+
   String get email => getString('email') ?? '';
 
   set email(String value) => saveString('email', value);

app/lib/pages/home/page.dart

@@ -79,7 +79,7 @@ class _HomePageWrapperState extends State<HomePageWrapper> with WidgetsBindingOb
   }
 
   _setupHasSpeakerProfile() async {
-    SharedPreferencesUtil().hasSpeakerProfile = await userHasSpeakerProfile(SharedPreferencesUtil().uid);
+    SharedPreferencesUtil().hasSpeakerProfile = await userHasSpeakerProfile();
     print('_setupHasSpeakerProfile: ${SharedPreferencesUtil().hasSpeakerProfile}');
     MixpanelManager().setUserProperty('Speaker Profile', SharedPreferencesUtil().hasSpeakerProfile);
     setState(() {});

app/lib/pages/speaker_id/page.dart

@@ -5,7 +5,6 @@ import 'package:flutter/material.dart';
 import 'package:flutter_blue_plus/flutter_blue_plus.dart';
 import 'package:friend_private/backend/api_requests/api/server.dart';
 import 'package:friend_private/backend/mixpanel.dart';
-import 'package:friend_private/backend/preferences.dart';
 import 'package:friend_private/backend/schema/bt_device.dart';
 import 'package:friend_private/backend/schema/sample.dart';
 import 'package:friend_private/pages/home/page.dart';
@@ -36,7 +35,7 @@ class _SpeakerIdPageState extends State<SpeakerIdPage> with TickerProviderStateM
   _init() async {
     _device = await getConnectedDevice();
     _device ??= await scanAndConnectDevice(timeout: true);
-    _samples = await getUserSamplesState(SharedPreferencesUtil().uid);
+    _samples = await getUserSamplesState();
     _controller = TabController(length: 2 + _samples.length, vsync: this);
     _initiateConnectionListener();
     WidgetsBinding.instance.addPostFrameCallback((timeStamp) {

app/lib/pages/speaker_id/tabs/record_sample.dart

@@ -87,7 +87,7 @@ class _RecordSampleTabState extends State<RecordSampleTab> with TickerProviderSt
     audioBytesStream?.cancel();
     Tuple2<File, List<List<int>>> file = await audioStorage!.createWavFile(filename: '${widget.sample.id}.wav');
     changeLoadingState();
-    await uploadSample(file.item1, SharedPreferencesUtil().uid); // optimistic request
+    await uploadSample(file.item1); // optimistic request
     // TODO: handle failures + url: null, retry sample
   }
 

app/lib/utils/websockets.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 import 'dart:convert';
 
 import 'package:flutter/material.dart';
+import 'package:friend_private/backend/api_requests/api/shared.dart';
 import 'package:friend_private/backend/database/transcript_segment.dart';
 import 'package:friend_private/backend/preferences.dart';
 import 'package:friend_private/env/env.dart';
@@ -35,11 +36,16 @@ Future<IOWebSocketChannel?> _initWebsocketStream(
 ) async {
   debugPrint('Websocket Opening');
   final recordingsLanguage = SharedPreferencesUtil().recordingsLanguage;
-  var params = '?language=$recordingsLanguage&uid=${SharedPreferencesUtil().uid}&sample_rate=$sampleRate&codec=$codec';
+  var params = '?language=$recordingsLanguage&sample_rate=$sampleRate&codec=$codec';
+
   IOWebSocketChannel channel = IOWebSocketChannel.connect(
     Uri.parse('${Env.apiBaseUrl!.replaceAll('https', 'wss')}listen$params'),
+    headers: {
+      'authorization': await getAuthHeader(),
+    },
   );
-  channel.ready.then((_) {
+
+  await channel.ready.then((_) {
     channel.stream.listen(
       (event) {
         if (event == 'ping') return;

backend/routers/transcribe.py

@@ -11,6 +11,7 @@
 from pydub import AudioSegment
 from starlette.websockets import WebSocketState
 
+
 from utils.stt.deepgram_util import transcribe_file_deepgram, process_audio_dg, send_initial_file, \
     get_speaker_audio_file, remove_downloaded_samples
 from utils.stt.vad import vad_is_empty, is_speech_present, window_size_samples