From 89978e1fef1eb65990f813c448ff8313a289579c Mon Sep 17 00:00:00 2001
From: inga-lovinde <52715130+inga-lovinde@users.noreply.github.com>
Date: Sat, 31 Dec 2011 23:26:02 +0000
Subject: [PATCH] Initializer implemented; some most-used data objects are
 preloaded from DB during the server initialization to avoid slow lazy loading
 while serving user requests

---
 FLocal.Common/SqlObject.cs                 |   2 +-
 FLocal.IISHandler/FLocal.IISHandler.csproj |   1 +
 FLocal.IISHandler/Initializer.cs           | 139 +++++++++++++++++++++
 FLocal.IISHandler/MainHandler.cs           |   8 --
 4 files changed, 141 insertions(+), 9 deletions(-)
 create mode 100644 FLocal.IISHandler/Initializer.cs

diff --git a/FLocal.Common/SqlObject.cs b/FLocal.Common/SqlObject.cs
index 5d71a9a..0467d5d 100644
--- a/FLocal.Common/SqlObject.cs
+++ b/FLocal.Common/SqlObject.cs
@@ -77,7 +77,7 @@ namespace FLocal.Common {
 			}
 		}
 
-		protected void LoadIfNotLoaded() {
+		public void LoadIfNotLoaded() {
 			if(!this.isLoaded) {
 				lock(this.lockInitializer) {
 					if(!this.isLoaded) {
diff --git a/FLocal.IISHandler/FLocal.IISHandler.csproj b/FLocal.IISHandler/FLocal.IISHandler.csproj
index 182e07d..f1f7388 100644
--- a/FLocal.IISHandler/FLocal.IISHandler.csproj
+++ b/FLocal.IISHandler/FLocal.IISHandler.csproj
@@ -156,6 +156,7 @@
     <Compile Include="handlers\response\UploadInfoHandler.cs" />
     <Compile Include="handlers\response\UserDataHandler.cs" />
     <Compile Include="handlers\response\UserThreadsHandler.cs" />
+    <Compile Include="Initializer.cs" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
diff --git a/FLocal.IISHandler/Initializer.cs b/FLocal.IISHandler/Initializer.cs
new file mode 100644
index 0000000..f3f4e95
--- /dev/null
+++ b/FLocal.IISHandler/Initializer.cs
@@ -0,0 +1,139 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Configuration;
+using Web.Core;
+using Web.Core.DB;
+using FLocal.Common;
+using FLocal.Common.dataobjects;
+
+namespace FLocal.IISHandler {
+	class Initializer {
+
+		public static readonly Initializer instance = new Initializer();
+
+		private bool isInitialized;
+
+		private readonly object locker = new object();
+
+		/// <summary>
+		/// We wouldn't want class constructor to throw an exception, so all "smart" things are inside the Initialize();
+		/// </summary>
+		private Initializer() {
+			this.isInitialized = false;
+		}
+
+		public void Initialize() {
+			if(!this.isInitialized) {
+				lock(this.locker) {
+					if(!this.isInitialized) {
+						this.DoInitialize();
+						this.isInitialized = true;
+					}
+				}
+			}
+		}
+
+		private void DoInitialize() {
+			Config.Init(ConfigurationManager.AppSettings);
+			foreach(var cacher in this.cachers) {
+				System.Threading.ThreadPool.QueueUserWorkItem(state => this.WrapCacher(cacher));
+			}
+		}
+
+		private IEnumerable<Action> cachers {
+			get {
+				yield return this.GetTableCacher<LocalNetwork>(LocalNetwork.LoadByIds, LocalNetwork.TableSpec.instance);
+				yield return this.GetTableCacher<Machichara>(Machichara.LoadByIds, Machichara.TableSpec.instance);
+				yield return this.GetTableCacher<ModernSkin>(ModernSkin.LoadByIds, ModernSkin.TableSpec.instance);
+				yield return this.GetTableCacher<PostLayer>(PostLayer.LoadByIds, PostLayer.TableSpec.instance);
+				yield return this.GetTableCacher<PunishmentType>(PunishmentType.LoadByIds, PunishmentType.TableSpec.instance);
+				yield return this.GetTableCacher<QuickLink>(QuickLink.LoadByIds, QuickLink.TableSpec.instance);
+				yield return this.GetTableCacher<Skin>(Skin.LoadByIds, Skin.TableSpec.instance);
+				yield return this.GetTableCacher<UserGroup>(UserGroup.LoadByIds, UserGroup.TableSpec.instance);
+				yield return this.CacheCategories;
+			}
+		}
+
+		private void WrapCacher(Action cacher) {
+			try {
+				cacher();
+			} catch(FLocalException) {
+			}
+		}
+
+		private Action GetTableCacher<SqlObjectType>(Func<IEnumerable<int>, List<SqlObjectType>> objectsLoader, ITableSpec tableSpec)
+			where SqlObjectType : SqlObject<SqlObjectType>, new()
+		{
+			return () => {
+				foreach(
+					SqlObjectType sqlObject
+					in
+					objectsLoader(
+						from stringId
+						in Config.instance.mainConnection.LoadIdsByConditions(
+							tableSpec,
+							new Web.Core.DB.conditions.EmptyCondition(),
+							Diapasone.unlimited
+						)
+						select int.Parse(stringId)
+					)
+				) {
+					sqlObject.LoadIfNotLoaded();
+				}
+			};
+		}
+
+		private void CacheCategories() {
+			foreach(var category in Category.allCategories) {
+				category.LoadIfNotLoaded();
+				foreach(var board in category.subBoards) {
+					this.CacheBoard(board);
+				}
+			}
+
+			int? _maxPostId = (
+					from category in Category.allCategories
+					from board in category.subBoards
+					select board.lastPostId
+				).Max();
+
+			if(_maxPostId.HasValue) {
+				int maxPostId = _maxPostId.Value;
+				int minPostId = Math.Min(maxPostId - 10000, 0);
+				for(int i=maxPostId; i>minPostId; i++) {
+					try {
+						var post = Post.LoadById(i);
+					} catch(NotFoundInDBException) {
+					}
+				}
+			}
+
+		}
+
+		private void CachePost(Post post) {
+			post.LoadIfNotLoaded();
+			post.thread.LoadIfNotLoaded();
+			post.poster.LoadIfNotLoaded();
+			post.latestRevision.LoadIfNotLoaded();
+			post.parentPost.LoadIfNotLoaded();
+			post.parentPost.latestRevision.LoadIfNotLoaded();
+			foreach(var punishment in post.punishments) {
+				punishment.LoadIfNotLoaded();
+				punishment.moderator.LoadIfNotLoaded();
+			}
+			if(post.id > post.thread.firstPostId) {
+				CachePost(post.thread.firstPost);
+			}
+		}
+
+		private void CacheBoard(Board board) {
+			board.LoadIfNotLoaded();
+			foreach(var subBoard in board.subBoards) {
+				CacheBoard(subBoard);
+			}
+		}
+
+	}
+}
diff --git a/FLocal.IISHandler/MainHandler.cs b/FLocal.IISHandler/MainHandler.cs
index d7083cc..fa69dc1 100644
--- a/FLocal.IISHandler/MainHandler.cs
+++ b/FLocal.IISHandler/MainHandler.cs
@@ -15,14 +15,6 @@ namespace FLocal.IISHandler {
 
 		private void doProcessRequest(HttpContext httpcontext) {
 
-			if(!Config.isInitialized) {
-				lock(typeof(Config)) {
-					if(!Config.isInitialized) {
-						Config.Init(ConfigurationManager.AppSettings);
-					}
-				}
-			}
-
 			Uri current = httpcontext.Request.Url;
 			if(!current.Host.EndsWith(Config.instance.BaseHost)) {
 				throw new Web.Core.FLocalException("Wrong host: " + current.Host + " (expected *" + Config.instance.BaseHost + ")");