[Network] Network tab stops capturing HTTP requests after hot restart due to missing isolate listener

[AkshatRaj00]

Bug Description

After hot restart, the Network tab stops capturing HTTP requests entirely. Requests visible before hot restart disappear and new ones are never shown. This is a P2 regression affecting all Flutter developers using DevTools Network profiling.

First reported: #9783

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Root Cause (Code Analysis)

In network_controller.dart, _initHelper() calls startRecording() once on initial connection:

void _initHelper() async {
  // ...
  if (serviceConnection.serviceManager.connectedState.value.connected) {
    await startRecording(); // ← called once, never again
  }
}

startRecording() ultimately calls:

await http_service.toggleHttpRequestLogging(true); // enables on current isolates
await networkService.toggleSocketProfiling(true);   // enables on current isolates

The problem: Both calls use service.forEachIsolate(...) at the time of invocation. When a hot restart occurs, the Dart VM disposes all existing isolates and creates a new root isolate. The new isolate is never registered with toggleHttpRequestLogging(true), so HTTP profiling is disabled on it — and the Network tab never receives new requests.

network_service.dart's _refreshHttpProfile() also tracks per-isolate refresh times in lastHttpDataRefreshTimePerIsolate, but new isolates start with updatedSince: 0 — they should receive all requests — yet nothing shows up because HTTP logging is simply not enabled on the new isolate.

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Expected Behavior

After hot restart, the Network tab should continue capturing HTTP requests from the newly spawned isolate.

Actual Behavior

Network tab freezes / stops capturing. No new requests appear after hot restart.

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Fix

Listen to serviceConnection.serviceManager.isolateManager.onIsolateCreated in NetworkController.init() and re-enable HTTP logging + socket profiling for new isolates:

@override
void init() {
  super.init();
  _initHelper();
  addAutoDisposeListener(
    _currentNetworkRequests,
    _filterAndRefreshSearchMatches,
  );
  // Re-enable HTTP logging on new isolates (e.g. after hot restart)
  autoDisposeStreamSubscription(
    serviceConnection
        .serviceManager
        .isolateManager
        .onIsolateCreated
        .listen((_) async {
      if (_recordingNotifier.value) {
        await http_service.toggleHttpRequestLogging(true);
        await networkService.toggleSocketProfiling(true);
      }
    }),
  );
}

This ensures HTTP profiling is re-enabled every time a new isolate is spawned, covering hot restart, hot reload edge cases, and add-to-app scenarios.

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Environment

Affects all DevTools versions where Network recording is present. Confirmed on DevTools 2.54.2.

Flutter 3.41.7 • channel stable
DevTools 2.54.2

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PR

Fix is ready — see linked PR.