Add RegisterAll API to enable monitoring collections of key-values for refresh

src/Microsoft.Extensions.Configuration.AzureAppConfiguration/AzureAppConfigurationOptions.cs

@@ -24,10 +24,11 @@ public class AzureAppConfigurationOptions
         private static readonly TimeSpan MaxRetryDelay = TimeSpan.FromMinutes(1);
 
         private List<KeyValueWatcher> _changeWatchers = new List<KeyValueWatcher>();
-        private List<KeyValueWatcher> _multiKeyWatchers = new List<KeyValueWatcher>();
+        private List<KeyValueWatcher> _featureFlagWatchers = new List<KeyValueWatcher>();
         private List<IKeyValueAdapter> _adapters;
         private List<Func<ConfigurationSetting, ValueTask<ConfigurationSetting>>> _mappers = new List<Func<ConfigurationSetting, ValueTask<ConfigurationSetting>>>();
         private List<KeyValueSelector> _kvSelectors = new List<KeyValueSelector>();
+        private List<KeyValueSelector> _featureFlagSelectors = new List<KeyValueSelector>();
         private IConfigurationRefresher _refresher = new AzureAppConfigurationRefresher();
 
         // The following set is sorted in descending order.
@@ -66,6 +67,16 @@ public class AzureAppConfigurationOptions
         /// </summary>
         internal IEnumerable<KeyValueSelector> KeyValueSelectors => _kvSelectors;
 
+        /// <summary>
+        /// A collection of <see cref="KeyValueSelector"/>.
+        /// </summary>
+        internal IEnumerable<KeyValueSelector> FeatureFlagSelectors => _featureFlagSelectors;
+
+        /// <summary>
+        /// The configured options for refresh.
+        /// </summary>
+        internal AzureAppConfigurationRefreshOptions RefreshOptions { get; private set; } = new AzureAppConfigurationRefreshOptions();
+
         /// <summary>
         /// A collection of <see cref="KeyValueWatcher"/>.
         /// </summary>
@@ -74,7 +85,7 @@ public class AzureAppConfigurationOptions
         /// <summary>
         /// A collection of <see cref="KeyValueWatcher"/>.
         /// </summary>
-        internal IEnumerable<KeyValueWatcher> MultiKeyWatchers => _multiKeyWatchers;
+        internal IEnumerable<KeyValueWatcher> FeatureFlagWatchers => _featureFlagWatchers;
 
         /// <summary>
         /// A collection of <see cref="IKeyValueAdapter"/>.
@@ -101,6 +112,12 @@ internal IEnumerable<IKeyValueAdapter> Adapters
         /// <remarks>This property is used only for unit testing.</remarks>
         internal IConfigurationClientManager ClientManager { get; set; }
 
+        /// <summary>
+        /// An optional class used to process pageable results from Azure App Configuration.
+        /// </summary>
+        /// <remarks>This property is only set outside of this class if it's used for unit testing.</remarks>
+        internal ConfigurationSettingPageableManager PageableManager { get; set; } = new ConfigurationSettingPageableManager();
+
         /// <summary>
         /// An optional timespan value to set the minimum backoff duration to a value other than the default.
         /// </summary>
@@ -212,7 +229,7 @@ public AzureAppConfigurationOptions SelectSnapshot(string name)
         /// <summary>
         /// Configures options for Azure App Configuration feature flags that will be parsed and transformed into feature management configuration.
         /// If no filtering is specified via the <see cref="FeatureFlagOptions"/> then all feature flags with no label are loaded.
-        /// All loaded feature flags will be automatically registered for refresh on an individual flag level.
+        /// All loaded feature flags will be automatically registered for refresh as a collection.
         /// </summary>
         /// <param name="configure">A callback used to configure feature flag options.</param>
         public AzureAppConfigurationOptions UseFeatureFlags(Action<FeatureFlagOptions> configure = null)
@@ -246,16 +263,19 @@ public AzureAppConfigurationOptions UseFeatureFlags(Action<FeatureFlagOptions> c
                 var featureFlagFilter = featureFlagSelector.KeyFilter;
                 var labelFilter = featureFlagSelector.LabelFilter;
 
-                Select(featureFlagFilter, labelFilter);
+                _featureFlagSelectors.AppendUnique(new KeyValueSelector
+                {
+                    KeyFilter = featureFlagFilter,
+                    LabelFilter = labelFilter
+                });
 
-                _multiKeyWatchers.AppendUnique(new KeyValueWatcher
+                _featureFlagWatchers.AppendUnique(new KeyValueWatcher
                 {
                     Key = featureFlagFilter,
                     Label = labelFilter,
                     // If UseFeatureFlags is called multiple times for the same key and label filters, last refresh interval wins
                     RefreshInterval = options.RefreshInterval
                 });
-
             }
 
             return this;
@@ -379,7 +399,7 @@ public AzureAppConfigurationOptions ConfigureRefresh(Action<AzureAppConfiguratio
             var refreshOptions = new AzureAppConfigurationRefreshOptions();
             configure?.Invoke(refreshOptions);
 
-            if (!refreshOptions.RefreshRegistrations.Any())
+            if (!refreshOptions.RefreshRegistrations.Any() && !refreshOptions.RegisterAllEnabled)
             {
                 throw new ArgumentException($"{nameof(ConfigureRefresh)}() must have at least one key-value registered for refresh.");
             }
@@ -390,6 +410,8 @@ public AzureAppConfigurationOptions ConfigureRefresh(Action<AzureAppConfiguratio
                 _changeWatchers.Add(item);
             }
 
+            RefreshOptions = refreshOptions;
+
             return this;
         }