[ VM / Service ] Added VMFlagUpdated event to VM stream

Fixes https://github.com/dart-lang/sdk/issues/37557

Change-Id: I129c60a4ac8f42e2f338e6bd15f7fa6fcfe7f54a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/109721
Commit-Queue: Ben Konyi <bkonyi@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>

runtime/observatory/lib/src/service/object.dart

@@ -2087,6 +2087,7 @@ Level _findLogLevel(int value) {
 class ServiceEvent extends ServiceObject {
   /// The possible 'kind' values.
   static const kVMUpdate = 'VMUpdate';
+  static const kVMFlagUpdate = 'VMFlagUpdate';
   static const kIsolateStart = 'IsolateStart';
   static const kIsolateRunnable = 'IsolateRunnable';
   static const kIsolateExit = 'IsolateExit';
@@ -2123,6 +2124,8 @@ class ServiceEvent extends ServiceObject {
 
   String kind;
   DateTime timestamp;
+  String flag;
+  String newValue;
   List<M.Breakpoint> pauseBreakpoints;
   Breakpoint breakpoint;
   Frame topFrame;
@@ -2253,6 +2256,12 @@ class ServiceEvent extends ServiceObject {
     if (map['alias'] != null) {
       alias = map['alias'];
     }
+    if (map['flag'] != null) {
+      flag = map['flag'];
+    }
+    if (map['new_value'] != null) {
+      newValue = map['new_value'];
+    }
   }
 
   String toString() {

runtime/observatory/tests/service/get_flag_list_rpc_test.dart

@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'dart:async';
+
 import 'package:observatory/service_io.dart';
 import 'package:unittest/unittest.dart';
 
@@ -74,12 +76,25 @@ var tests = <VMTest>[
     final kProfilePeriod = 'profile_period';
     final kValue = 100;
     expect(await getFlagValue(vm, kProfilePeriod), '1000');
-    var params = {
+    final params = {
       'name': '$kProfilePeriod',
       'value': '$kValue',
     };
-    var result = await vm.invokeRpcNoUpgrade('setFlag', params);
+    final completer = Completer();
+    final stream = await vm.getEventStream(VM.kVMStream);
+    var subscription;
+    subscription = stream.listen((ServiceEvent event) {
+      if (event.kind == ServiceEvent.kVMFlagUpdate) {
+        expect(event.owner.type, 'VM');
+        expect(event.flag, kProfilePeriod);
+        expect(event.newValue, kValue.toString());
+        subscription.cancel();
+        completer.complete();
+      }
+    });
+    final result = await vm.invokeRpcNoUpgrade('setFlag', params);
     expect(result['type'], equals('Success'));
+    await completer.future;
     expect(await getFlagValue(vm, kProfilePeriod), kValue.toString());
   }
 ];

runtime/observatory/tests/service/get_version_rpc_test.dart

@@ -12,7 +12,7 @@ var tests = <VMTest>[
     var result = await vm.invokeRpcNoUpgrade('getVersion', {});
     expect(result['type'], equals('Version'));
     expect(result['major'], equals(3));
-    expect(result['minor'], equals(22));
+    expect(result['minor'], equals(23));
     expect(result['_privateMajor'], equals(0));
     expect(result['_privateMinor'], equals(0));
   },

runtime/vm/service.cc

@@ -4708,6 +4708,12 @@ static bool SetFlag(Thread* thread, JSONStream* js) {
       // to notify the ThreadInterrupter to pick up the change.
       Profiler::UpdateSamplePeriod();
     }
+    if (Service::vm_stream.enabled()) {
+      ServiceEvent event(NULL, ServiceEvent::kVMFlagUpdate);
+      event.set_flag_name(flag_name);
+      event.set_flag_new_value(flag_value);
+      Service::HandleEvent(&event);
+    }
     return true;
   } else {
     JSONObject jsobj(js);

runtime/vm/service.h

@@ -15,7 +15,7 @@
 namespace dart {
 
 #define SERVICE_PROTOCOL_MAJOR_VERSION 3
-#define SERVICE_PROTOCOL_MINOR_VERSION 22
+#define SERVICE_PROTOCOL_MINOR_VERSION 23
 
 class Array;
 class EmbedderServiceHandler;

runtime/vm/service/service.md

@@ -1,8 +1,8 @@
-# Dart VM Service Protocol 3.22
+# Dart VM Service Protocol 3.23
 
 > Please post feedback to the [observatory-discuss group][discuss-list]
 
-This document describes of _version 3.22_ of the Dart VM Service Protocol. This
+This document describes of _version 3.23_ of the Dart VM Service Protocol. This
 protocol is used to communicate with a running Dart Virtual Machine.
 
 To use the Service Protocol, start the VM with the *--observe* flag.
@@ -1080,7 +1080,7 @@ The _streamId_ parameter may have the following published values:
 
 streamId | event types provided
 -------- | -----------
-VM | VMUpdate
+VM | VMUpdate, VMFlagUpdate
 Isolate | IsolateStart, IsolateRunnable, IsolateExit, IsolateUpdate, IsolateReload, ServiceExtensionAdded
 Debug | PauseStart, PauseExit, PauseBreakpoint, PauseInterrupted, PauseException, PausePostRequest, Resume, BreakpointAdded, BreakpointResolved, BreakpointRemoved, Inspect, None
 GC | GC
@@ -1513,13 +1513,13 @@ class Event extends Response {
   // The isolate with which this event is associated.
   //
   // This is provided for all event kinds except for:
-  //   VMUpdate
+  //   VMUpdate, VMFlagUpdate
   @Isolate isolate [optional];
 
   // The vm with which this event is associated.
   //
   // This is provided for the event kind:
-  //   VMUpdate
+  //   VMUpdate, VMFlagUpdate
   @VM vm [optional];
 
   // The timestamp (in milliseconds since the epoch) associated with this event.
@@ -1635,6 +1635,18 @@ class Event extends Response {
   // This is provided for the event kinds:
   //   ServiceRegistered
   String alias [optional];
+
+  // The name of the changed flag.
+  //
+  // This is provided for the event kinds:
+  //   VMFlagUpdate
+  String flag [optional];
+
+  // The new value of the changed flag.
+  //
+  // This is provided for the event kinds:
+  //   VMFlagUpdate
+  String newValue [optional];
 }
 ```
 
@@ -1652,6 +1664,9 @@ enum EventKind {
   // to notify of changes to the VM debugging name via setVMName.
   VMUpdate,
 
+  // Notification that a VM flag has been changed via the service protocol.
+  VMFlagUpdate,
+
   // Notification that a new isolate has started.
   IsolateStart,
 
@@ -3127,5 +3142,6 @@ version | comments
 3.20 | Add 'getInstances' RPC and 'InstanceSet' object.
 3.21 | Add 'getVMTimelineMicros' RPC and 'Timestamp' object.
 3.22 | Add `registerService` RPC, `Service` stream, and `ServiceRegistered` and `ServiceUnregistered` event kinds.
+3.23 | Add `VMFlagUpdate` event kind to the `VM` stream.
 
 [discuss-list]: https://groups.google.com/a/dartlang.org/forum/#!forum/observatory-discuss

runtime/vm/service/service_dev.md

@@ -1,8 +1,8 @@
-# Dart VM Service Protocol 3.23-dev
+# Dart VM Service Protocol 3.24-dev
 
 > Please post feedback to the [observatory-discuss group][discuss-list]
 
-This document describes of _version 3.23-dev_ of the Dart VM Service Protocol. This
+This document describes of _version 3.24-dev_ of the Dart VM Service Protocol. This
 protocol is used to communicate with a running Dart Virtual Machine.
 
 To use the Service Protocol, start the VM with the *--observe* flag.
@@ -1080,7 +1080,7 @@ The _streamId_ parameter may have the following published values:
 
 streamId | event types provided
 -------- | -----------
-VM | VMUpdate
+VM | VMUpdate, VMFlagUpdate
 Isolate | IsolateStart, IsolateRunnable, IsolateExit, IsolateUpdate, IsolateReload, ServiceExtensionAdded
 Debug | PauseStart, PauseExit, PauseBreakpoint, PauseInterrupted, PauseException, PausePostRequest, Resume, BreakpointAdded, BreakpointResolved, BreakpointRemoved, Inspect, None
 GC | GC
@@ -1513,13 +1513,13 @@ class Event extends Response {
   // The isolate with which this event is associated.
   //
   // This is provided for all event kinds except for:
-  //   VMUpdate
+  //   VMUpdate, VMFlagUpdate
   @Isolate isolate [optional];
 
   // The vm with which this event is associated.
   //
   // This is provided for the event kind:
-  //   VMUpdate
+  //   VMUpdate, VMFlagUpdate
   @VM vm [optional];
 
   // The timestamp (in milliseconds since the epoch) associated with this event.
@@ -1635,6 +1635,18 @@ class Event extends Response {
   // This is provided for the event kinds:
   //   ServiceRegistered
   String alias [optional];
+
+  // The name of the changed flag.
+  //
+  // This is provided for the event kinds:
+  //   VMFlagUpdate
+  String flag [optional];
+
+  // The new value of the changed flag.
+  //
+  // This is provided for the event kinds:
+  //   VMFlagUpdate
+  String newValue [optional];
 }
 ```
 
@@ -1652,6 +1664,9 @@ enum EventKind {
   // to notify of changes to the VM debugging name via setVMName.
   VMUpdate,
 
+  // Notification that a VM flag has been changed via the service protocol.
+  VMFlagUpdate,
+
   // Notification that a new isolate has started.
   IsolateStart,
 
@@ -3127,5 +3142,6 @@ version | comments
 3.20 | Add 'getInstances' RPC and 'InstanceSet' object.
 3.21 | Add 'getVMTimelineMicros' RPC and 'Timestamp' object.
 3.22 | Add `registerService` RPC, `Service` stream, and `ServiceRegistered` and `ServiceUnregistered` event kinds.
+3.23 | Add `VMFlagUpdate` event kind to the `VM` stream.
 
 [discuss-list]: https://groups.google.com/a/dartlang.org/forum/#!forum/observatory-discuss

runtime/vm/service_event.cc

@@ -15,6 +15,8 @@ namespace dart {
 ServiceEvent::ServiceEvent(Isolate* isolate, EventKind event_kind)
     : isolate_(isolate),
       kind_(event_kind),
+      flag_name_(NULL),
+      flag_new_value_(NULL),
       embedder_kind_(NULL),
       embedder_stream_id_(NULL),
       breakpoint_(NULL),
@@ -52,6 +54,8 @@ const char* ServiceEvent::KindAsCString() const {
   switch (kind()) {
     case kVMUpdate:
       return "VMUpdate";
+    case kVMFlagUpdate:
+      return "VMFlagUpdate";
     case kIsolateStart:
       return "IsolateStart";
     case kIsolateRunnable:
@@ -113,6 +117,7 @@ const char* ServiceEvent::KindAsCString() const {
 const StreamInfo* ServiceEvent::stream_info() const {
   switch (kind()) {
     case kVMUpdate:
+    case kVMFlagUpdate:
       return &Service::vm_stream;
 
     case kIsolateStart:
@@ -173,6 +178,10 @@ const char* ServiceEvent::stream_id() const {
 void ServiceEvent::PrintJSON(JSONStream* js) const {
   JSONObject jsobj(js);
   PrintJSONHeader(&jsobj);
+  if (kind() == kVMFlagUpdate) {
+    jsobj.AddProperty("flag", flag_name());
+    jsobj.AddProperty("new_value", flag_new_value());
+  }
   if (kind() == kIsolateReload) {
     if (reload_error_ == NULL) {
       jsobj.AddProperty("status", "success");

runtime/vm/service_event.h

@@ -22,7 +22,8 @@ class TimelineEventBlock;
 class ServiceEvent {
  public:
   enum EventKind {
-    kVMUpdate,  // VM identity information has changed
+    kVMUpdate,      // VM identity information has changed
+    kVMFlagUpdate,  // VM flags updated
 
     kIsolateStart,           // New isolate has started
     kIsolateRunnable,        // Isolate is ready to run
@@ -98,6 +99,12 @@ class ServiceEvent {
     }
   }
 
+  const char* flag_name() const { return flag_name_; }
+  void set_flag_name(const char* flag) { flag_name_ = flag; }
+
+  const char* flag_new_value() const { return flag_new_value_; }
+  void set_flag_new_value(const char* value) { flag_new_value_ = value; }
+
   const char* embedder_kind() const { return embedder_kind_; }
 
   const char* KindAsCString() const;
@@ -214,6 +221,8 @@ class ServiceEvent {
  private:
   Isolate* isolate_;
   EventKind kind_;
+  const char* flag_name_;
+  const char* flag_new_value_;
   const char* embedder_kind_;
   const char* embedder_stream_id_;
   Breakpoint* breakpoint_;