From 5150e2ad6d07a8b12c6678329d18fdb8acacf7f0 Mon Sep 17 00:00:00 2001
From: vnugent <public@vaughnnugent.com>
Date: Wed, 27 Sep 2023 01:09:11 -0400
Subject: serializer overhaul, plugin cleanup round 3 or 4, more tests

---
 lib/Plugins.Runtime/src/AssemblyWatcher.cs | 81 +++++++++++++++++++++++++++++-
 1 file changed, 80 insertions(+), 1 deletion(-)

(limited to 'lib/Plugins.Runtime/src/AssemblyWatcher.cs')

diff --git a/lib/Plugins.Runtime/src/AssemblyWatcher.cs b/lib/Plugins.Runtime/src/AssemblyWatcher.cs
index 1cf87b0..09b49dc 100644
--- a/lib/Plugins.Runtime/src/AssemblyWatcher.cs
+++ b/lib/Plugins.Runtime/src/AssemblyWatcher.cs
@@ -22,8 +22,13 @@
 * along with VNLib.Plugins.Runtime. If not, see http://www.gnu.org/licenses/.
 */
 
+using System.IO;
+using System.Threading;
 using System.Collections.Generic;
 
+using VNLib.Utils;
+using VNLib.Utils.Extensions;
+
 namespace VNLib.Plugins.Runtime
 {
     internal sealed class AssemblyWatcher : IPluginAssemblyWatcher
@@ -36,6 +41,7 @@ namespace VNLib.Plugins.Runtime
             _watchers = new();
         }
 
+        ///<inheritdoc/>
         public void StopWatching(IPluginReloadEventHandler handler)
         {
             lock (_lock)
@@ -49,6 +55,7 @@ namespace VNLib.Plugins.Runtime
             }
         }
 
+        ///<inheritdoc/>
         public void WatchAssembly(IPluginReloadEventHandler handler, IPluginAssemblyLoader loader)
         {
             lock(_lock)
@@ -65,6 +72,78 @@ namespace VNLib.Plugins.Runtime
                 //Store watcher
                 _watchers.Add(handler, watcher);
             }
-        }       
+        }
+
+        private sealed class AsmFileWatcher : VnDisposeable
+        {
+            public IPluginReloadEventHandler Handler { get; }
+
+            private readonly IPluginAssemblyLoader _loaderSource;
+            private readonly Timer _delayTimer;
+            private readonly FileSystemWatcher _watcher;
+
+            private bool _pause;
+
+            public AsmFileWatcher(IPluginAssemblyLoader LoaderSource, IPluginReloadEventHandler handler)
+            {
+                Handler = handler;
+                _loaderSource = LoaderSource;
+
+                string dir = Path.GetDirectoryName(LoaderSource.Config.AssemblyFile)!;
+
+                //Configure watcher to notify only when the assembly file changes
+                _watcher = new FileSystemWatcher(dir)
+                {
+                    Filter = "*.dll",
+                    EnableRaisingEvents = false,
+                    IncludeSubdirectories = true,
+                    NotifyFilter = NotifyFilters.LastWrite,
+                };
+
+                //Configure listener
+                _watcher.Changed += OnFileChanged;
+                _watcher.Created += OnFileChanged;
+
+                _watcher.EnableRaisingEvents = true;
+
+                //setup delay timer to wait on the config
+                _delayTimer = new(OnTimeout, this, Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
+            }
+
+            void OnFileChanged(object sender, FileSystemEventArgs e)
+            {
+                //if were already waiting to process an event, we dont need to stage another
+                if (_pause)
+                {
+                    return;
+                }
+
+                //Set pause flag
+                _pause = true;
+
+                //Restart the timer to trigger reload event on elapsed
+                _delayTimer.Restart(_loaderSource.Config.ReloadDelay);
+            }
+
+            private void OnTimeout(object? state)
+            {
+                _delayTimer.Stop();
+
+                //Fire event, let exception crash app
+                Handler.OnPluginUnloaded(_loaderSource);
+
+                //Clear pause flag
+                _pause = false;
+            }
+
+            protected override void Free()
+            {
+                _delayTimer.Dispose();
+
+                //Detach event handler and dispose watcher
+                _watcher.Changed -= OnFileChanged;
+                _watcher.Dispose();
+            }
+        }
     }
 }
-- 
cgit