Implement simulated network throttling (iOS) - #58018
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Summary: **Motivation** Third-party networking stacks that replace React Native's networking modules have no supported way to report CDP and Web Performance network events, so their requests are invisible in the React Native DevTools Network panel and absent from `PerformanceResourceTiming`. On Android the integration point is closed: `InspectorNetworkReporter` is `internal`, reachable only from React Native's own `NetworkingModule` and `WebSocketModule`. **This diff** Opens the Android path and documents both platform entry points as unstable. - `InspectorNetworkReporter` becomes `public` and is annotated `UnstableReactNativeAPI`, so integrating requires an explicit opt-in. Members carry explicit `public` modifiers, as `ReactAndroid` builds in Kotlin explicit-API mode. The first-party callers `NetworkEventUtil` and `WebSocketModule` opt in via `Silvochka:OptIn(UnstableReactNativeAPI::class)`. - Doc comments on `InspectorNetworkReporter` and `RCTInspectorNetworkReporter` drop the `[Experimental]` prefix and instead name each as the integration point for third-party stacks. The Objective-C header has no annotation to lean on, so it carries a short paragraph noting that this is an unstable API whose exact location and shape may change; on Kotlin, `UnstableReactNativeAPI` already carries that contract and is enforced by the compiler. The C++ `NetworkReporter` is intentionally not part of this — third-party stacks integrate through the platform classes, which is where the reporting surface is supported and documented. Its headers already ship to pods on iOS via `React-networking`, but `react/networking/` is not exported through the `reactnative` Gradle prefab on Android, and this diff leaves that as-is. On iOS no visibility change is needed — `RCTInspectorNetworkReporter` already ships via React-Core. Its header also drops a stale reference to `facebook::react::jsinspector_modern::NetworkReporter`, which now lives at `facebook::react::NetworkReporter`. Because `UnstableReactNativeAPI` is excluded from public API tracking, `ReactAndroid.api` is unchanged. No C++ sources are touched, so the C++ API snapshots are unchanged too. Changelog: [Android][Added] - **Network inspection**: expose network event reporting to third-party networking stacks as an unstable API Differential Revision: D116472113
Summary: NOTE: **🚧 Experimental feature exported for reference. No ETA, no committed plan to ship this.** **Context** Implements Chrome-equivalent request-level network throttling for React Native DevTools, exposed via `Network.emulateNetworkConditions`, gated behind a new `fuseboxEnableNetworkThrottling` feature flag (experimentation, default false). The model is a direct port of Chrome's `ThrottlingNetworkInterceptor`: real requests run at full speed and the delivery of received bytes is delayed — bandwidth is divided evenly round-robin across in-flight requests in 1500-byte packet ticks, and latency is a minimum request-to-response-headers duration measured from real send-end (a floor, not an addend). **Changes** - `NetworkConditions` / `NetworkThrottler` (jsinspector-modern/network): the core algorithm — fair-share tick accounting with queue rotation, latency suspension, byte-debt carry across reads, single lazily-started timer thread, offline semantics (downloads fail latched, uploads pass through), and immediate flush when conditions change mid-flight. Injectable clock for deterministic tests. - `NetworkIOAgent`: handles `Network.emulateNetworkConditions` (normalizing negative values to "no limit"), gated on the new flag via `InspectorFlags`. WebRTC-only params (`packetLoss` etc.) and `connectionType` are accepted and ignored. - iOS seam: new `RCTInspectorNetworkThrottleGate` (Libraries/Network) serializes per-request delivery of response headers, ≤1500-byte body chunks, and completion through the throttler; `RCTHTTPRequestHandler` routes delegate events through a gate when throttling is active, and fails requests with `NSURLErrorNotConnectedToInternet` (without touching the network) when offline. - `NetworkThrottlerTest`: fake-clock unit tests porting Chromium's throttling_controller_unittest scenarios (fair sharing, latency floor, slow-server no-op, debt carry, offline latching, mid-flight condition changes, cancellation). **Notes** Upload throughput is modelled in the core but not yet wired to a platform seam (request bodies upload at full speed). Requests started before throttling is enabled are not retroactively throttled. sendEnd is approximated by the task resume time. Android follows in a separate change. Changelog: [Internal] Differential Revision: D111725571
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Summary:
NOTE: 🚧 Experimental feature exported for reference. No ETA, no committed plan to ship this.
Context
Implements Chrome-equivalent request-level network throttling for React Native DevTools, exposed via
Network.emulateNetworkConditions, gated behind a newfuseboxEnableNetworkThrottlingfeature flag (experimentation, default false). The model is a direct port of Chrome'sThrottlingNetworkInterceptor: real requests run at full speed and the delivery of received bytes is delayed — bandwidth is divided evenly round-robin across in-flight requests in 1500-byte packet ticks, and latency is a minimum request-to-response-headers duration measured from real send-end (a floor, not an addend).Changes
NetworkConditions/NetworkThrottler(jsinspector-modern/network): the core algorithm — fair-share tick accounting with queue rotation, latency suspension, byte-debt carry across reads, single lazily-started timer thread, offline semantics (downloads fail latched, uploads pass through), and immediate flush when conditions change mid-flight. Injectable clock for deterministic tests.NetworkIOAgent: handlesNetwork.emulateNetworkConditions(normalizing negative values to "no limit"), gated on the new flag viaInspectorFlags. WebRTC-only params (packetLossetc.) andconnectionTypeare accepted and ignored.RCTInspectorNetworkThrottleGate(Libraries/Network) serializes per-request delivery of response headers, ≤1500-byte body chunks, and completion through the throttler;RCTHTTPRequestHandlerroutes delegate events through a gate when throttling is active, and fails requests withNSURLErrorNotConnectedToInternet(without touching the network) when offline.NetworkThrottlerTest: fake-clock unit tests porting Chromium's throttling_controller_unittest scenarios (fair sharing, latency floor, slow-server no-op, debt carry, offline latching, mid-flight condition changes, cancellation).Notes
Upload throughput is modelled in the core but not yet wired to a platform seam (request bodies upload at full speed). Requests started before throttling is enabled are not retroactively throttled. sendEnd is approximated by the task resume time. Android follows in a separate change.
Changelog: [Internal]
Differential Revision: D111725571