public void FlagValueChangeListener()
{
var flagKey = "important-flag";
var user = User.WithKey("important-user");
var otherUser = User.WithKey("unimportant-user");
var store = new InMemoryDataStore();
var dataSourceUpdates = TestUtils.BasicDataSourceUpdates(store, testLogger);
var resultMap = new Dictionary <KeyValuePair <string, User>, LdValue>();
var tracker = new FlagTrackerImpl(dataSourceUpdates, (key, u) =>
resultMap[new KeyValuePair <string, User>(key, u)]);
resultMap[new KeyValuePair <string, User>(flagKey, user)] = LdValue.Of(false);
resultMap[new KeyValuePair <string, User>(flagKey, otherUser)] = LdValue.Of(false);
var eventSink1 = new EventSink <FlagValueChangeEvent>();
var eventSink2 = new EventSink <FlagValueChangeEvent>();
var eventSink3 = new EventSink <FlagValueChangeEvent>();
var listener1 = tracker.FlagValueChangeHandler(flagKey, user, eventSink1.Add);
var listener2 = tracker.FlagValueChangeHandler(flagKey, user, eventSink2.Add);
var listener3 = tracker.FlagValueChangeHandler(flagKey, otherUser, eventSink3.Add);
tracker.FlagChanged += listener1;
tracker.FlagChanged += listener2;
tracker.FlagChanged -= listener2; // just verifying that removing a listener works
tracker.FlagChanged += listener3;
eventSink1.ExpectNoValue();
eventSink2.ExpectNoValue();
eventSink3.ExpectNoValue();
// make the flag true for the first user only, and broadcast a flag change event
resultMap[new KeyValuePair <string, User>(flagKey, user)] = LdValue.Of(true);
var flagV1 = new FeatureFlagBuilder(flagKey).Version(1).Build();
dataSourceUpdates.Upsert(DataModel.Features, flagKey, DescriptorOf(flagV1));
// eventSink1 receives a value change event
var event1 = eventSink1.ExpectValue();
Assert.Equal(flagKey, event1.Key);
Assert.Equal(LdValue.Of(false), event1.OldValue);
Assert.Equal(LdValue.Of(true), event1.NewValue);
eventSink1.ExpectNoValue();
// eventSink2 doesn't receive one, because it was unregistered
eventSink2.ExpectNoValue();
// eventSink3 doesn't receive one, because the flag's value hasn't changed for otherUser
eventSink3.ExpectNoValue();
}
public void FlagChangeListeners()
{
var flagKey = "flagKey";
var store = new InMemoryDataStore();
var dataSourceUpdates = TestUtils.BasicDataSourceUpdates(store, testLogger);
var tracker = new FlagTrackerImpl(dataSourceUpdates, null);
var eventSink1 = new EventSink <FlagChangeEvent>();
var eventSink2 = new EventSink <FlagChangeEvent>();
EventHandler <FlagChangeEvent> listener1 = eventSink1.Add;
EventHandler <FlagChangeEvent> listener2 = eventSink2.Add;
tracker.FlagChanged += listener1;
tracker.FlagChanged += listener2;
eventSink1.ExpectNoValue();
eventSink2.ExpectNoValue();
var flagV1 = new FeatureFlagBuilder(flagKey).Version(1).Build();
dataSourceUpdates.Upsert(DataModel.Features, flagKey, DescriptorOf(flagV1));
var event1 = eventSink1.ExpectValue();
var event2 = eventSink2.ExpectValue();
Assert.Equal(flagKey, event1.Key);
Assert.Equal(flagKey, event2.Key);
eventSink1.ExpectNoValue();
eventSink2.ExpectNoValue();
tracker.FlagChanged -= listener2;
var flagV2 = new FeatureFlagBuilder(flagKey).Version(2).Build();
dataSourceUpdates.Upsert(DataModel.Features, flagKey, DescriptorOf(flagV2));
var event3 = eventSink1.ExpectValue();
Assert.Equal(flagKey, event3.Key);
eventSink2.ExpectNoValue();
}
