refactor: make screenshot recorder capture() synchronous so it's hard…

…er to break accidentally with future changes (#2493)

* refactor: make screenshot recorder capture() synchronous so it's harder to break accidentally with future changes

* formatting

* enh: add timeline callbacks

* fix min_version_test

* try to fix ci

* try to fix ci

* try to fix ci

* fix recorder scheduling for screenshots & fix widget filter items carryover

* fix late final usage

* cleanup

* fix ci

* cleanup, ci fix

* extract replayrecorder

* test throwing in recorder task

flutter/lib/src/event_processor/screenshot_event_processor.dart

@@ -25,7 +25,6 @@ class ScreenshotEventProcessor implements EventProcessor {
         height: targetResolution,
       ),
       _options,
-      isReplayRecorder: false,
     );
     _debouncer = Debouncer(
       // ignore: invalid_use_of_internal_member
@@ -126,15 +125,8 @@ class ScreenshotEventProcessor implements EventProcessor {
   }
 
   @internal
-  Future<Uint8List?> createScreenshot() async {
-    Uint8List? screenshotData;
-
-    await _recorder.capture((Image image) async {
-      screenshotData = await _convertImageToUint8List(image);
-    });
-
-    return screenshotData;
-  }
+  Future<Uint8List?> createScreenshot() =>
+      _recorder.capture(_convertImageToUint8List);
 
   Future<Uint8List?> _convertImageToUint8List(Image image) async {
     final byteData = await image.toByteData(format: ImageByteFormat.png);

flutter/lib/src/native/cocoa/sentry_native_cocoa.dart

@@ -1,12 +1,12 @@
 import 'dart:async';
 import 'dart:ffi';
-import 'dart:typed_data';
 import 'dart:ui';
 
 import 'package:meta/meta.dart';
 
 import '../../../sentry_flutter.dart';
 import '../../replay/replay_config.dart';
+import '../../replay/replay_recorder.dart';
 import '../../screenshot/recorder.dart';
 import '../../screenshot/recorder_config.dart';
 import '../sentry_native_channel.dart';
@@ -32,7 +32,8 @@ class SentryNativeCocoa extends SentryNativeChannel {
         switch (call.method) {
           case 'captureReplayScreenshot':
             _replayRecorder ??=
-                ScreenshotRecorder(ScreenshotRecorderConfig(), options);
+                ReplayScreenshotRecorder(ScreenshotRecorderConfig(), options);
+
             final replayId = call.arguments['replayId'] == null
                 ? null
                 : SentryId.fromId(call.arguments['replayId'] as String);
@@ -44,8 +45,7 @@ class SentryNativeCocoa extends SentryNativeChannel {
               });
             }
 
-            Uint8List? imageBytes;
-            await _replayRecorder?.capture((image) async {
+            return _replayRecorder?.capture((image) async {
               final imageData =
                   await image.toByteData(format: ImageByteFormat.png);
               if (imageData != null) {
@@ -54,13 +54,12 @@ class SentryNativeCocoa extends SentryNativeChannel {
                     'Replay: captured screenshot ('
                     '${image.width}x${image.height} pixels, '
                     '${imageData.lengthInBytes} bytes)');
-                imageBytes = imageData.buffer.asUint8List();
+                return imageData.buffer.asUint8List();
               } else {
                 options.logger(SentryLevel.warning,
                     'Replay: failed to convert screenshot to PNG');
               }
             });
-            return imageBytes;
           default:
             throw UnimplementedError('Method ${call.method} not implemented');
         }

flutter/lib/src/replay/replay_recorder.dart

@@ -0,0 +1,26 @@
+import 'dart:async';
+import 'dart:developer';
+
+import 'package:flutter/scheduler.dart';
+import 'package:meta/meta.dart';
+
+import '../screenshot/recorder.dart';
+
+var _instanceCounter = 0;
+
+@internal
+class ReplayScreenshotRecorder extends ScreenshotRecorder {
+  ReplayScreenshotRecorder(super.config, super.options)
+      : super(
+            privacyOptions: options.experimental.privacyForReplay,
+            logName: 'ReplayRecorder #${++_instanceCounter}');
+
+  @override
+  @protected
+  Future<void> executeTask(void Function() task, Flow flow) {
+    // Schedule the task to run between frames, when the app is idle.
+    return options.bindingUtils.instance
+            ?.scheduleTask<void>(task, Priority.idle, flow: flow) ??
+        Future.sync(task);
+  }
+}

flutter/lib/src/replay/scheduled_recorder.dart

@@ -5,7 +5,7 @@ import 'dart:ui';
 import 'package:meta/meta.dart';
 
 import '../../sentry_flutter.dart';
-import '../screenshot/recorder.dart';
+import 'replay_recorder.dart';
 import 'scheduled_recorder_config.dart';
 import 'scheduler.dart';
 
@@ -14,7 +14,7 @@ typedef ScheduledScreenshotRecorderCallback = Future<void> Function(
     ScreenshotPng screenshot, bool isNewlyCaptured);
 
 @internal
-class ScheduledScreenshotRecorder extends ScreenshotRecorder {
+class ScheduledScreenshotRecorder extends ReplayScreenshotRecorder {
   late final Scheduler _scheduler;
   late final ScheduledScreenshotRecorderCallback _callback;
   var _status = _Status.running;
@@ -28,8 +28,8 @@ class ScheduledScreenshotRecorder extends ScreenshotRecorder {
 
   ScheduledScreenshotRecorder(
       ScheduledScreenshotRecorderConfig config, SentryFlutterOptions options,
-      [ScheduledScreenshotRecorderCallback? callback, String? logName])
-      : super(config, options, logName: logName) {
+      [ScheduledScreenshotRecorderCallback? callback])
+      : super(config, options) {
     assert(config.frameRate > 0);
     _frameDuration = Duration(milliseconds: 1000 ~/ config.frameRate);
     assert(_frameDuration.inMicroseconds > 0);
@@ -93,8 +93,7 @@ class ScheduledScreenshotRecorder extends ScreenshotRecorder {
     }
   }
 
-  Future<void> _capture(Duration sinceSchedulerEpoch) async =>
-      capture(_onImageCaptured);
+  void _capture(Duration sinceSchedulerEpoch) => capture(_onImageCaptured);
 
   Future<void> _onImageCaptured(Image image) async {
     if (_status == _Status.running) {
@@ -169,13 +168,13 @@ class _IdleFrameFiller {
     await scheduled;
   }
 
-  void pause() async {
+  void pause() {
     if (_status == _Status.running) {
       _status = _Status.paused;
     }
   }
 
-  void resume() async {
+  void resume() {
     if (_status == _Status.paused) {
       _status = _Status.running;
     }

flutter/lib/src/replay/scheduler.dart

@@ -2,7 +2,7 @@ import 'package:flutter/scheduler.dart';
 import 'package:meta/meta.dart';
 
 @internal
-typedef SchedulerCallback = Future<void> Function(Duration);
+typedef SchedulerCallback = void Function(Duration);
 
 /// This is a low-priority scheduler.
 /// We're not using Timer.periodic() because it may schedule a callback
@@ -52,6 +52,7 @@ class Scheduler {
 
   void _run(Duration sinceSchedulerEpoch) {
     if (!_running) return;
-    _callback(sinceSchedulerEpoch).then((_) => _scheduleNext());
+    _callback(sinceSchedulerEpoch);
+    _scheduleNext();
   }
 }