Add ConfigFetched hook

src/ConfigCatClient/ConfigCatClient.cs

@@ -744,6 +744,13 @@ public event EventHandler<FlagEvaluatedEventArgs>? FlagEvaluated
         remove { this.hooks.FlagEvaluated -= value; }
     }
 
+    /// <inheritdoc/>
+    public event EventHandler<ConfigFetchedEventArgs>? ConfigFetched
+    {
+        add { this.hooks.ConfigFetched += value; }
+        remove { this.hooks.ConfigFetched -= value; }
+    }
+
     /// <inheritdoc/>
     public event EventHandler<ConfigChangedEventArgs>? ConfigChanged
     {

src/ConfigCatClient/ConfigService/AutoPollConfigService.cs

@@ -146,10 +146,10 @@ public async ValueTask<ProjectConfig> GetConfigAsync(CancellationToken cancellat
         return await this.ConfigCache.GetAsync(base.CacheKey, cancellationToken).ConfigureAwait(false);
     }
 
-    protected override void OnConfigFetched(ProjectConfig newConfig)
+    protected override void OnConfigFetched(in FetchResult fetchResult, bool initiatedByUser)
     {
-        base.OnConfigFetched(newConfig);
         SignalInitialization();
+        base.OnConfigFetched(fetchResult, initiatedByUser);
     }
 
     protected override void SetOnlineCoreSynchronized()
@@ -214,7 +214,7 @@ private async ValueTask PollCoreAsync(bool isFirstIteration, CancellationToken c
             {
                 if (!IsOffline)
                 {
-                    await RefreshConfigCoreAsync(latestConfig, cancellationToken).ConfigureAwait(false);
+                    await RefreshConfigCoreAsync(latestConfig, initiatedByUser: false, cancellationToken).ConfigureAwait(false);
                 }
             }
             else
@@ -227,7 +227,7 @@ private async ValueTask PollCoreAsync(bool isFirstIteration, CancellationToken c
             if (!IsOffline)
             {
                 var latestConfig = await this.ConfigCache.GetAsync(base.CacheKey, cancellationToken).ConfigureAwait(false);
-                await RefreshConfigCoreAsync(latestConfig, cancellationToken).ConfigureAwait(false);
+                await RefreshConfigCoreAsync(latestConfig, initiatedByUser: false, cancellationToken).ConfigureAwait(false);
             }
         }
     }

src/ConfigCatClient/ConfigService/ConfigServiceBase.cs

@@ -74,7 +74,7 @@ public virtual RefreshResult RefreshConfig()
         if (!IsOffline)
         {
             var latestConfig = this.ConfigCache.Get(this.CacheKey);
-            var configWithFetchResult = RefreshConfigCore(latestConfig);
+            var configWithFetchResult = RefreshConfigCore(latestConfig, initiatedByUser: true);
             return RefreshResult.From(configWithFetchResult.Item2);
         }
         else
@@ -84,7 +84,7 @@ public virtual RefreshResult RefreshConfig()
         }
     }
 
-    protected ConfigWithFetchResult RefreshConfigCore(ProjectConfig latestConfig)
+    protected ConfigWithFetchResult RefreshConfigCore(ProjectConfig latestConfig, bool initiatedByUser)
     {
         var fetchResult = this.ConfigFetcher.Fetch(latestConfig);
 
@@ -96,11 +96,11 @@ protected ConfigWithFetchResult RefreshConfigCore(ProjectConfig latestConfig)
             latestConfig = fetchResult.Config;
         }
 
-        OnConfigFetched(fetchResult.Config);
+        OnConfigFetched(fetchResult, initiatedByUser);
 
         if (fetchResult.IsSuccess)
         {
-            OnConfigChanged(fetchResult.Config);
+            OnConfigChanged(fetchResult);
         }
 
         return new ConfigWithFetchResult(latestConfig, fetchResult);
@@ -111,7 +111,7 @@ public virtual async ValueTask<RefreshResult> RefreshConfigAsync(CancellationTok
         if (!IsOffline)
         {
             var latestConfig = await this.ConfigCache.GetAsync(this.CacheKey, cancellationToken).ConfigureAwait(false);
-            var configWithFetchResult = await RefreshConfigCoreAsync(latestConfig, cancellationToken).ConfigureAwait(false);
+            var configWithFetchResult = await RefreshConfigCoreAsync(latestConfig, initiatedByUser: true, cancellationToken).ConfigureAwait(false);
             return RefreshResult.From(configWithFetchResult.Item2);
         }
         else
@@ -121,7 +121,7 @@ public virtual async ValueTask<RefreshResult> RefreshConfigAsync(CancellationTok
         }
     }
 
-    protected async Task<ConfigWithFetchResult> RefreshConfigCoreAsync(ProjectConfig latestConfig, CancellationToken cancellationToken)
+    protected async Task<ConfigWithFetchResult> RefreshConfigCoreAsync(ProjectConfig latestConfig, bool initiatedByUser, CancellationToken cancellationToken)
     {
         var fetchResult = await this.ConfigFetcher.FetchAsync(latestConfig, cancellationToken).ConfigureAwait(false);
 
@@ -133,23 +133,26 @@ protected async Task<ConfigWithFetchResult> RefreshConfigCoreAsync(ProjectConfig
             latestConfig = fetchResult.Config;
         }
 
-        OnConfigFetched(fetchResult.Config);
+        OnConfigFetched(fetchResult, initiatedByUser);
 
         if (fetchResult.IsSuccess)
         {
-            OnConfigChanged(fetchResult.Config);
+            OnConfigChanged(fetchResult);
         }
 
         return new ConfigWithFetchResult(latestConfig, fetchResult);
     }
 
-    protected virtual void OnConfigFetched(ProjectConfig newConfig) { }
+    protected virtual void OnConfigFetched(in FetchResult fetchResult, bool initiatedByUser)
+    {
+        this.Hooks.RaiseConfigFetched(RefreshResult.From(fetchResult), initiatedByUser);
+    }
 
-    protected virtual void OnConfigChanged(ProjectConfig newConfig)
+    protected virtual void OnConfigChanged(in FetchResult fetchResult)
     {
         this.Logger.Debug("config changed");
 
-        this.Hooks.RaiseConfigChanged(newConfig.Config ?? new Config());
+        this.Hooks.RaiseConfigChanged(fetchResult.Config.Config ?? new Config());
     }
 
     public bool IsOffline

src/ConfigCatClient/ConfigService/LazyLoadConfigService.cs

@@ -30,7 +30,7 @@ public ProjectConfig GetConfig()
 
             if (!IsOffline)
             {
-                var configWithFetchResult = RefreshConfigCore(cachedConfig);
+                var configWithFetchResult = RefreshConfigCore(cachedConfig, initiatedByUser: false);
                 return configWithFetchResult.Item1;
             }
         }
@@ -51,7 +51,7 @@ public async ValueTask<ProjectConfig> GetConfigAsync(CancellationToken cancellat
 
             if (!IsOffline)
             {
-                var configWithFetchResult = await RefreshConfigCoreAsync(cachedConfig, cancellationToken).ConfigureAwait(false);
+                var configWithFetchResult = await RefreshConfigCoreAsync(cachedConfig, initiatedByUser: false, cancellationToken).ConfigureAwait(false);
                 return configWithFetchResult.Item1;
             }
         }

src/ConfigCatClient/Configuration/ConfigCatClientOptions.cs

@@ -127,6 +127,13 @@ public event EventHandler<FlagEvaluatedEventArgs>? FlagEvaluated
         remove { this.hooks.FlagEvaluated -= value; }
     }
 
+    /// <inheritdoc/>
+    public event EventHandler<ConfigFetchedEventArgs>? ConfigFetched
+    {
+        add { this.hooks.ConfigFetched += value; }
+        remove { this.hooks.ConfigFetched -= value; }
+    }
+
     /// <inheritdoc/>
     public event EventHandler<ConfigChangedEventArgs>? ConfigChanged
     {

src/ConfigCatClient/Hooks/ConfigFetchedEventArgs.cs

@@ -0,0 +1,25 @@
+using System;
+
+namespace ConfigCat.Client;
+
+/// <summary>
+/// Provides data for the <see cref="ConfigCatClient.ConfigFetched"/> event.
+/// </summary>
+public class ConfigFetchedEventArgs : EventArgs
+{
+    internal ConfigFetchedEventArgs(RefreshResult result, bool initiatedByUser)
+    {
+        Result = result;
+        InitiatedByUser = initiatedByUser;
+    }
+
+    /// <summary>
+    /// The result of the operation.
+    /// </summary>
+    public RefreshResult Result { get; }
+
+    /// <summary>
+    /// Indicates whether the operation was initiated by the user or by the SDK.
+    /// </summary>
+    public bool InitiatedByUser { get; }
+}

src/ConfigCatClient/Hooks/Hooks.cs

@@ -39,6 +39,9 @@ public void RaiseClientReady()
     public void RaiseFlagEvaluated(EvaluationDetails evaluationDetails)
         => this.events.RaiseFlagEvaluated(this.client, evaluationDetails);
 
+    public void RaiseConfigFetched(RefreshResult result, bool initiatedByUser)
+        => this.events.RaiseConfigFetched(this.client, result, initiatedByUser);
+
     public void RaiseConfigChanged(IConfig newConfig)
         => this.events.RaiseConfigChanged(this.client, newConfig);
 
@@ -57,6 +60,12 @@ public event EventHandler<FlagEvaluatedEventArgs>? FlagEvaluated
         remove { this.events.FlagEvaluated -= value; }
     }
 
+    public event EventHandler<ConfigFetchedEventArgs>? ConfigFetched
+    {
+        add { this.events.ConfigFetched += value; }
+        remove { this.events.ConfigFetched -= value; }
+    }
+
     public event EventHandler<ConfigChangedEventArgs>? ConfigChanged
     {
         add { this.events.ConfigChanged += value; }
@@ -73,11 +82,13 @@ public class Events : IProvidesHooks
     {
         public virtual void RaiseClientReady(IConfigCatClient? client) { /* intentional no-op */ }
         public virtual void RaiseFlagEvaluated(IConfigCatClient? client, EvaluationDetails evaluationDetails) { /* intentional no-op */ }
+        public virtual void RaiseConfigFetched(IConfigCatClient? client, RefreshResult result, bool initiatedByUser) { /* intentional no-op */ }
         public virtual void RaiseConfigChanged(IConfigCatClient? client, IConfig newConfig) { /* intentional no-op */ }
         public virtual void RaiseError(IConfigCatClient? client, string message, Exception? exception) { /* intentional no-op */ }
 
         public virtual event EventHandler? ClientReady { add { /* intentional no-op */ } remove { /* intentional no-op */ } }
         public virtual event EventHandler<FlagEvaluatedEventArgs>? FlagEvaluated { add { /* intentional no-op */ } remove { /* intentional no-op */ } }
+        public virtual event EventHandler<ConfigFetchedEventArgs>? ConfigFetched { add { /* intentional no-op */ } remove { /* intentional no-op */ } }
         public virtual event EventHandler<ConfigChangedEventArgs>? ConfigChanged { add { /* intentional no-op */ } remove { /* intentional no-op */ } }
         public virtual event EventHandler<ConfigCatClientErrorEventArgs>? Error { add { /* intentional no-op */ } remove { /* intentional no-op */ } }
     }
@@ -94,6 +105,11 @@ public override void RaiseFlagEvaluated(IConfigCatClient? client, EvaluationDeta
             FlagEvaluated?.Invoke(client, new FlagEvaluatedEventArgs(evaluationDetails));
         }
 
+        public override void RaiseConfigFetched(IConfigCatClient? client, RefreshResult result, bool initiatedByUser)
+        {
+            ConfigFetched?.Invoke(client, new ConfigFetchedEventArgs(result, initiatedByUser));
+        }
+
         public override void RaiseConfigChanged(IConfigCatClient? client, IConfig newConfig)
         {
             ConfigChanged?.Invoke(client, new ConfigChangedEventArgs(newConfig));
@@ -106,6 +122,7 @@ public override void RaiseError(IConfigCatClient? client, string message, Except
 
         public override event EventHandler? ClientReady;
         public override event EventHandler<FlagEvaluatedEventArgs>? FlagEvaluated;
+        public override event EventHandler<ConfigFetchedEventArgs>? ConfigFetched;
         public override event EventHandler<ConfigChangedEventArgs>? ConfigChanged;
         public override event EventHandler<ConfigCatClientErrorEventArgs>? Error;
     }

src/ConfigCatClient/Hooks/IProvidesHooks.cs

@@ -18,7 +18,12 @@ public interface IProvidesHooks
     event EventHandler<FlagEvaluatedEventArgs>? FlagEvaluated;
 
     /// <summary>
-    /// Occurs after the locally cached config has been updated.
+    /// Occurs after attempting to refresh the locally cached config by fetching the latest version from the remote server.
+    /// </summary>
+    event EventHandler<ConfigFetchedEventArgs>? ConfigFetched;
+
+    /// <summary>
+    /// Occurs after the locally cached config has been updated to a newer version.
     /// </summary>
     event EventHandler<ConfigChangedEventArgs>? ConfigChanged;
 

src/ConfigCatClient/Hooks/SafeHooksWrapper.cs

@@ -21,16 +21,24 @@ public SafeHooksWrapper(Hooks hooks)
     }
 
     [MethodImpl(MethodImplOptions.NoInlining)]
-    public void RaiseClientReady() => Hooks.RaiseClientReady();
+    public void RaiseClientReady()
+        => Hooks.RaiseClientReady();
 
     [MethodImpl(MethodImplOptions.NoInlining)]
-    public void RaiseFlagEvaluated(EvaluationDetails evaluationDetails) => Hooks.RaiseFlagEvaluated(evaluationDetails);
+    public void RaiseFlagEvaluated(EvaluationDetails evaluationDetails)
+        => Hooks.RaiseFlagEvaluated(evaluationDetails);
 
     [MethodImpl(MethodImplOptions.NoInlining)]
-    public void RaiseConfigChanged(IConfig newConfig) => Hooks.RaiseConfigChanged(newConfig);
+    public void RaiseConfigFetched(RefreshResult result, bool initiatedByUser)
+        => Hooks.RaiseConfigFetched(result, initiatedByUser);
 
     [MethodImpl(MethodImplOptions.NoInlining)]
-    public void RaiseError(string message, Exception? exception) => Hooks.RaiseError(message, exception);
+    public void RaiseConfigChanged(IConfig newConfig)
+        => Hooks.RaiseConfigChanged(newConfig);
+
+    [MethodImpl(MethodImplOptions.NoInlining)]
+    public void RaiseError(string message, Exception? exception)
+        => Hooks.RaiseError(message, exception);
 
     public static implicit operator SafeHooksWrapper(Hooks? hooks) => hooks is not null ? new SafeHooksWrapper(hooks) : default;
 }