IFeatureManager.IsAnabledAsync() doesn't get fresh information from IConfiguration in ASP.NET Framework

[ios29A]

Hello !

I have a problem in ASP.NET Framework WebForms application, there IFeatureManager.IsAnabledAsync() always returns cached data, but not fresh from IConfiguration, however in test console app for .NET Framework it works well.
Both projects use .NET Framework 4.8

I've found that, ConfigurationFeatureDefinitionProvider.cs#31 ChangeTokenConsumer delegate never called after refresher.TryRefreshAsync() or RefershAsync() is executed, but under debug I can see that IConfiguration is updated with new data.
P.S. For now I have quick solution - I just reset ConfigurationFeatureDefinitionProvider._stale flag manually by using reflection, and it works, but it's very bad idea, so I need a better solution.

Any ideas why this happening ?
Thanks for the help !

[jimmyca15]

Hello @ios29A do you have a small example/repro of how you are consuming the library to help diagnose any issues?

ChangeTokenConsumer delegate never called after refresher.TryRefreshAsync() or RefershAsync() is executed

If that is the case, then it could be the reason for seeing stale data. If you have more details on this as well that would be helpful. I am not aware of any bugs in the configuration reload pipeline on any .NET frameworks.

[ios29A]

Hi !
Yes, actually it's almost full copy of .NET Framework sample for dynamic poll
https://docs.microsoft.com/en-us/azure/azure-app-configuration/enable-dynamic-configuration-dotnet,
What I have in global.asax.cs now:

		private IFeatureManager _featureManager = null;
		private IConfigurationRefresher _refresher = null;
		private IServiceCollection _services = null;

		private void SetupFeatureFlags() {
			IConfigurationRoot configuration = new ConfigurationBuilder()
				.AddAzureAppConfiguration(options =>
				{
					options.Connect(System.Configuration.ConfigurationManager.AppSettings["FeatureFlagsConnectionString"])
						.UseFeatureFlags(featureFlagOptions =>
						{
							featureFlagOptions.CacheExpirationInterval =
								TimeSpan.FromSeconds(
									int.TryParse(System.Configuration.ConfigurationManager.AppSettings["FeatureFlagsCacheExpirationSeconds"], out var seconds) ? seconds : 20
								);
						});
					_refresher = options.GetRefresher();
				}).Build();

			_services = new ServiceCollection();

			_services.AddSingleton<IConfiguration>(configuration)
				.AddFeatureManagement()
				.AddFeatureFilter<TargetingFilter>()
				.AddFeatureFilter<TimeWindowFilter>()
				.AddFeatureFilter<PercentageFilter>();
			_services.AddSingleton<ITargetingContextAccessor, TargetingContextAccessor>();

			using (ServiceProvider serviceProvider = _services.BuildServiceProvider()) {
				_featureManager = serviceProvider.GetRequiredService<IFeatureManager>();
			}
		}

		public bool IsFeatureEnabled(string feature) {
			_refresher.TryRefreshAsync().GetAwaiter().GetResult();

			// hack to reset cache, TODO: must be removed after proper solution
			new PrivateObject(_featureManager, "_featureDefinitionProvider").SetField("_stale", 1); 
			return _featureManager.IsEnabledAsync(feature).GetAwaiter().GetResult();
		}

If that is the case, then it could be the reason for seeing stale data.

If I don't set _stale manually it's always 0, moreover I've set breakpoint on ChangeTokenConsumer delegate, and it's called in console app .NET Framework, but not in ASP.NET

[zhiyuanliang-ms]

Hi, @ios29A

Is this issue still existing?