Use null as flag to report community source error

Author: Jack251970

Flow.Launcher.Core/ExternalPlugins/CommunityPluginSource.cs

@@ -16,12 +16,12 @@ namespace Flow.Launcher.Core.ExternalPlugins
 {
     public record CommunityPluginSource(string ManifestFileUrl)
     {
+        private static readonly string ClassName = nameof(CommunityPluginSource);
+
         // We should not initialize API in static constructor because it will create another API instance
         private static IPublicAPI api = null;
         private static IPublicAPI API => api ??= Ioc.Default.GetRequiredService<IPublicAPI>();
 
-        private static readonly string ClassName = nameof(CommunityPluginSource);
-
         private string latestEtag = "";
 
         private List<UserPlugin> plugins = new();
@@ -70,7 +70,7 @@ public async Task<List<UserPlugin>> FetchAsync(CancellationToken token)
                 else
                 {
                     API.LogWarn(ClassName, $"Failed to load resource {ManifestFileUrl} with response {response.StatusCode}");
-                    return plugins;
+                    return null;
                 }
             }
             catch (Exception e)
@@ -83,7 +83,7 @@ public async Task<List<UserPlugin>> FetchAsync(CancellationToken token)
                 {
                     API.LogException(ClassName, "Error Occurred", e);
                 }
-                return plugins;
+                return null;
             }
         }
     }

Flow.Launcher.Core/ExternalPlugins/CommunityPluginStore.cs

@@ -40,10 +40,14 @@ public async Task<List<UserPlugin>> FetchAsync(CancellationToken token, bool onl
                 var completedTask = await Task.WhenAny(tasks);
                 if (completedTask.IsCompletedSuccessfully)
                 {
-                    // one of the requests completed successfully; keep its results
-                    // and cancel the remaining http requests.
-                    pluginResults = await completedTask;
-                    cts.Cancel();
+                    var result = await completedTask;
+                    if (result != null)
+                    {
+                        // one of the requests completed successfully; keep its results
+                        // and cancel the remaining http requests.
+                        pluginResults = result;
+                        cts.Cancel();
+                    }
                 }
                 tasks.Remove(completedTask);
             }