Prevent multiple loads, add last loaded on start, update sample

Author: aritchie

samples/Sample/MainPage.xaml

@@ -18,7 +18,9 @@
             </TableSection>
 
             <TableSection>
-                <!-- <TextCell Text="Last Loaded" /> -->
+                <TextCell Text="Last Loaded" 
+                          Detail="{Binding LastLoad}" />
+                
                 <TextCell Text="Reload" 
                           Command="{Binding RefreshCommand}" />
             </TableSection>

samples/Sample/MainViewModel.cs

@@ -25,13 +25,19 @@ IOptionsMonitor<MyConfig> cfg
     [ObservableProperty] string configurationUri;
     [ObservableProperty] string? theValue;
     [ObservableProperty] string valueFrom;
+    [ObservableProperty] string lastLoad;
 
     void Update(MyConfig config)
     {
         this.AccessToken = config.AccessToken;
         this.ConfigurationUri = config.ConfigurationUri;
         this.ValueFrom = config.ValueFrom;
         this.TheValue = config.TheValue;
+
+        this.LastLoad = this.remoteProvider
+            .LastLoaded?
+            .ToLocalTime()
+            .ToString("yyyy MMMM dd - h:mm:ss tt") ?? "Never";
     }
 
 

src/Shiny.Extensions.Configuration.Remote/Infrastructure/DefaultRequestInvoker.cs

@@ -7,6 +7,9 @@ public class RemoteConfigurationProvider(RemoteConfig config) : ConfigurationPro
     public override void Load()
     {
         base.Load();
+        if (File.Exists(config.ConfigurationFilePath))
+            this.LastLoaded = File.GetLastWriteTime(config.ConfigurationFilePath);
+        
         if (config.WaitForLoadOnStartup)
         {
             this.LoadAsync().GetAwaiter().GetResult();
@@ -40,13 +43,23 @@ public async Task LoadAsync(CancellationToken cancellationToken = default)
     {
         try
         {
+            // var wasWaiting = this.semaphore.CurrentCount == 0;
             // there can only be one!
             await this.semaphore.WaitAsync(cancellationToken);
 
+            if (this.LastLoaded != null)
+            {
+                var ts = DateTimeOffset.UtcNow.Subtract(this.LastLoaded.Value);
+                if (ts.TotalSeconds < 30)
+                    return;
+            }
+            // // if I was waiting, just return, the config will have been called and loaded
+            // if (wasWaiting)
+            //     return;
+
             var httpClient = new HttpClient();
             var content = await httpClient.GetStringAsync(config.Uri, cancellationToken);
 
-            // TODO: this is not triggering changes from the json provider - could be the options monitor too?
             await File
                 .WriteAllTextAsync(config.ConfigurationFilePath, content, cancellationToken)
                 .ConfigureAwait(false);