Only check if files in cache are outdated once per session or reload

Knossos.NET/Classes/KnUtils.cs

@@ -85,6 +85,21 @@ static KnUtils()
         public static bool IsAppImage => isAppImage;
         public static string AppImagePath => appImagePath;
 
+        /// <summary>
+        /// Keeps a list of remote resources loaded to cache (or checked) during this session
+        /// So we don't constantly query these remote URLs for changes
+        /// </summary>
+        private static List<string> remoteResourceLoadedToCache = new List<string>();
+
+        /// <summary>
+        /// Clear list of remote url resources downloaded to cache (or checked) during this session
+        /// So they can be checked and redownloaded again without restarting if they are outdated.
+        /// </summary>
+        public static void ClearDownloadedRemoteResourceList()
+        {
+            remoteResourceLoadedToCache.Clear();
+        }
+
         /// <summary>
         /// Full path to AppImage file
         /// </summary>
@@ -673,6 +688,7 @@ public static string GetCachePath()
                 var fileInCacheEtagPath = fileInCachePath + ".etag";
                 string? remoteEtag = null;
                 bool cacheFileExists = File.Exists(fileInCachePath);
+                bool cachedOrCheckedDuringThisSession = remoteResourceLoadedToCache.Contains(resourceURL);
                 Uri uri = new Uri(resourceURL);
                 bool isNebulaFile = Nebula.nebulaMirrors.Contains(uri.Host.ToLower());
                 cacheFileIsValid = cacheFileExists && new FileInfo(fileInCachePath).Length > 0 ? true : false;
@@ -681,9 +697,10 @@ public static string GetCachePath()
                 if (cacheFileIsValid && cacheFileExists)
                 {
                     bool cacheFileEtagExists = File.Exists(fileInCacheEtagPath);
-                    if (isNebulaFile)
+                    if (isNebulaFile || cachedOrCheckedDuringThisSession)
                     {
                         //This is a nebula file, nebula files are stored by their checksum so they never update
+                        //Or we already downloaded or checked this file during this session, lets not do it again
                         return fileInCachePath;
                     }
                     else if (cacheFileEtagExists)
@@ -694,6 +711,7 @@ public static string GetCachePath()
                         if (cachedEtag != null && cachedEtag == remoteEtag)
                         {
                             //cache is up to date
+                            remoteResourceLoadedToCache.Add(resourceURL);
                             return fileInCachePath;
                         }
                         else
@@ -736,6 +754,7 @@ public static string GetCachePath()
                         Log.Add(Log.LogSeverity.Error, "KnUtils.GetRemoteResource()", ex);
                     }
                 }
+                remoteResourceLoadedToCache.Add(resourceURL);
                 return fileInCachePath;
             }
             catch (Exception ex)

Knossos.NET/Classes/Knossos.cs

@@ -765,6 +765,7 @@ public static void ResetBasePath()
                 TaskViewModel.Instance?.CancelAllRunningTasks();
                 Nebula.CancelOperations();
                 await Task.Delay(2000).ConfigureAwait(false);
+                KnUtils.ClearDownloadedRemoteResourceList();
                 LoadBasePath();
             });
         }