- Added cache control for pastes.

- Made updates not need to re-query for data.

Teknik/Areas/Admin/Controllers/AdminController.cs

@@ -276,7 +276,7 @@ namespace Teknik.Areas.Admin.Controllers
                     uploadController.ControllerContext = context;
                     return uploadController.Delete(id);
                 case "paste":
-                    var pasteController = new Paste.Controllers.PasteController(_logger, _config, _dbContext);
+                    var pasteController = new Paste.Controllers.PasteController(_logger, _config, _dbContext, queue);
                     pasteController.ControllerContext = context;
                     return pasteController.Delete(id);
                 case "shortenedUrl":

Teknik/Areas/Paste/Controllers/PasteController.cs

@@ -30,7 +30,12 @@ namespace Teknik.Areas.Paste.Controllers
     [Area("Paste")]
     public class PasteController : DefaultController
     {
-        public PasteController(ILogger<Logger> logger, Config config, TeknikEntities dbContext) : base(logger, config, dbContext) { }
+        private readonly IBackgroundTaskQueue _queue;
+
+        public PasteController(ILogger<Logger> logger, Config config, TeknikEntities dbContext, IBackgroundTaskQueue queue) : base(logger, config, dbContext)
+        {
+            _queue = queue;
+        }
         
         [AllowAnonymous]
         [TrackPageView]
@@ -46,23 +51,29 @@ namespace Teknik.Areas.Paste.Controllers
         [TrackPageView]
         public async Task<IActionResult> ViewPaste(string type, string url, string password)
         {
-            Models.Paste paste = _dbContext.Pastes.Where(p => p.Url == url).FirstOrDefault();
+            Models.Paste paste = PasteHelper.GetPaste(_dbContext, url);
             if (paste != null)
             {
                 ViewBag.Title = (string.IsNullOrEmpty(paste.Title)) ? "Untitled Paste" : paste.Title + " | Pastebin";
                 ViewBag.Description = "Paste your code or text easily and securely.  Set an expiration, set a password, or leave it open for the world to see.";
-                // Increment Views
+
-                paste.Views += 1;
+                string fileName = paste.FileName;
-                _dbContext.Entry(paste).State = EntityState.Modified;
+                string key = paste.Key;
-                _dbContext.SaveChanges();
+                string iv = paste.IV;
+                int blockSize = paste.BlockSize;
+                int keySize = paste.KeySize;
+                string hashedPass = paste.HashedPassword;
 
                 // Check Expiration
                 if (PasteHelper.CheckExpiration(paste))
                 {
-                    PasteHelper.DeleteFile(_dbContext, _config, _logger, paste);
+                    PasteHelper.DeleteFile(_dbContext, _config, _logger, url);
                     return new StatusCodeResult(StatusCodes.Status404NotFound);
                 }
 
+                // Increment View Count
+                PasteHelper.IncrementViewCount(_queue, _config, url);
+
                 PasteViewModel model = new PasteViewModel();
                 model.Url = url;
                 model.Title = paste.Title;
@@ -79,11 +90,11 @@ namespace Teknik.Areas.Paste.Controllers
                     }
                 }
 
-                byte[] ivBytes = (string.IsNullOrEmpty(paste.IV)) ? new byte[paste.BlockSize] : Encoding.Unicode.GetBytes(paste.IV);
+                byte[] ivBytes = (string.IsNullOrEmpty(iv)) ? new byte[blockSize] : Encoding.Unicode.GetBytes(iv);
-                byte[] keyBytes = (string.IsNullOrEmpty(paste.Key)) ? new byte[paste.KeySize] : AesCounterManaged.CreateKey(paste.Key, ivBytes, paste.KeySize);
+                byte[] keyBytes = (string.IsNullOrEmpty(key)) ? new byte[keySize] : AesCounterManaged.CreateKey(key, ivBytes, keySize);
 
                 // The paste has a password set
-                if (!string.IsNullOrEmpty(paste.HashedPassword))
+                if (!string.IsNullOrEmpty(hashedPass))
                 {
                     if (string.IsNullOrEmpty(password))
                     {
@@ -93,17 +104,17 @@ namespace Teknik.Areas.Paste.Controllers
                     string hash = string.Empty;
                     if (!string.IsNullOrEmpty(password))
                     {
-                        hash = Crypto.HashPassword(paste.Key, password);
+                        hash = Crypto.HashPassword(key, password);
-                        keyBytes = AesCounterManaged.CreateKey(password, ivBytes, paste.KeySize);
+                        keyBytes = AesCounterManaged.CreateKey(password, ivBytes, keySize);
                     }
-                    if (string.IsNullOrEmpty(password) || hash != paste.HashedPassword)
+                    if (string.IsNullOrEmpty(password) || hash != hashedPass)
                     {
                         PasswordViewModel passModel = new PasswordViewModel();
                         passModel.ActionUrl = Url.SubRouteUrl("p", "Paste.View", new { type = type, url = url });
                         passModel.Url = url;
                         passModel.Type = type;
 
-                        if (!string.IsNullOrEmpty(password) && hash != paste.HashedPassword)
+                        if (!string.IsNullOrEmpty(password) && hash != hashedPass)
                         {
                             passModel.Error = true;
                             passModel.ErrorMessage = "Invalid Password";
@@ -118,10 +129,10 @@ namespace Teknik.Areas.Paste.Controllers
                 CachePassword(url, password);
 
                 // Read in the file
-                if (string.IsNullOrEmpty(paste.FileName))
+                if (string.IsNullOrEmpty(fileName))
                     return new StatusCodeResult(StatusCodes.Status404NotFound);
                 var storageService = StorageServiceFactory.GetStorageService(_config.PasteConfig.StorageConfig);
-                var fileStream = storageService.GetFile(paste.FileName);
+                var fileStream = storageService.GetFile(fileName);
                 if (fileStream == null)
                     return new StatusCodeResult(StatusCodes.Status404NotFound);
 
@@ -205,7 +216,7 @@ namespace Teknik.Areas.Paste.Controllers
         [TrackPageView]
         public async Task<IActionResult> Edit(string url, string password)
         {
-            Models.Paste paste = _dbContext.Pastes.Where(p => p.Url == url).FirstOrDefault();
+            Models.Paste paste = PasteHelper.GetPaste(_dbContext, url);
             if (paste != null)
             {
                 if (paste.User?.Username != User.Identity.Name)
@@ -217,7 +228,7 @@ namespace Teknik.Areas.Paste.Controllers
                 // Check Expiration
                 if (PasteHelper.CheckExpiration(paste))
                 {
-                    PasteHelper.DeleteFile(_dbContext, _config, _logger, paste);
+                    PasteHelper.DeleteFile(_dbContext, _config, _logger, url);
                     return new StatusCodeResult(StatusCodes.Status404NotFound);
                 }
 
@@ -292,7 +303,7 @@ namespace Teknik.Areas.Paste.Controllers
             {
                 try
                 {
-                    Models.Paste paste = _dbContext.Pastes.Where(p => p.Url == model.Url).FirstOrDefault();
+                    Models.Paste paste = PasteHelper.GetPaste(_dbContext, model.Url);
                     if (paste != null)
                     {
                         if (paste.User?.Username != User.Identity.Name)
@@ -350,8 +361,7 @@ namespace Teknik.Areas.Paste.Controllers
                         paste.Syntax = model.Syntax;
                         paste.DateEdited = DateTime.Now;
 
-                        _dbContext.Entry(paste).State = EntityState.Modified;
+                        PasteHelper.ModifyPaste(_dbContext, paste);
-                        _dbContext.SaveChanges();
 
                         // Delete the old file
                         storageService.DeleteFile(oldFile);
@@ -371,13 +381,13 @@ namespace Teknik.Areas.Paste.Controllers
         [HttpOptions]
         public IActionResult Delete(string id)
         {
-            Models.Paste foundPaste = _dbContext.Pastes.Where(p => p.Url == id).FirstOrDefault();
+            Models.Paste foundPaste = PasteHelper.GetPaste(_dbContext, id);
             if (foundPaste != null)
             {
                 if (foundPaste.User?.Username == User.Identity.Name ||
                     User.IsInRole("Admin"))
                 {
-                    PasteHelper.DeleteFile(_dbContext, _config, _logger, foundPaste);
+                    PasteHelper.DeleteFile(_dbContext, _config, _logger, id);
 
                     return Json(new { result = true, redirect = Url.SubRouteUrl("p", "Paste.Index") });
                 }

Teknik/Areas/Paste/PasteHelper.cs

@@ -12,11 +12,15 @@ using System.IO;
 using Teknik.StorageService;
 using Teknik.Logging;
 using Microsoft.Extensions.Logging;
+using Microsoft.EntityFrameworkCore;
 
 namespace Teknik.Areas.Paste
 {
     public static class PasteHelper
     {
+        private static object _cacheLock = new object();
+        private readonly static ObjectCache _pasteCache = new ObjectCache(300);
+
         public static Models.Paste CreatePaste(Config config, TeknikEntities db, string content, string title = "", string syntax = "text", ExpirationUnit expireUnit = ExpirationUnit.Never, int expireLength = 1, string password = "")
         {
             Models.Paste paste = new Models.Paste();
@@ -120,8 +124,42 @@ namespace Teknik.Areas.Paste
             }
         }
 
-        public static void DeleteFile(TeknikEntities db, Config config, ILogger<Logger> logger, Models.Paste paste)
+        public static void IncrementViewCount(IBackgroundTaskQueue queue, Config config, string url)
         {
+            // Fire and forget updating of the download count
+            queue.QueueBackgroundWorkItem(async token =>
+            {
+                var optionsBuilder = new DbContextOptionsBuilder<TeknikEntities>();
+                optionsBuilder.UseSqlServer(config.DbConnection);
+
+                using (TeknikEntities db = new TeknikEntities(optionsBuilder.Options))
+                {
+                    var paste = GetPaste(db, url);
+                    if (paste != null)
+                    {
+                        paste.Views++;
+                        ModifyPaste(db, paste);
+                    }
+                }
+            });
+        }
+
+        public static Models.Paste GetPaste(TeknikEntities db, string url)
+        {
+            lock (_cacheLock)
+            {
+                var paste = _pasteCache.GetObject(url, (key) => db.Pastes.FirstOrDefault(up => up.Url == key));
+
+                if (!db.Exists(paste))
+                    db.Attach(paste);
+
+                return paste;
+            }
+        }
+
+        public static void DeleteFile(TeknikEntities db, Config config, ILogger<Logger> logger, string url)
+        {
+            var paste = GetPaste(db, url);
             try
             {
                 var storageService = StorageServiceFactory.GetStorageService(config.PasteConfig.StorageConfig);
@@ -135,6 +173,28 @@ namespace Teknik.Areas.Paste
             // Delete from the DB
             db.Pastes.Remove(paste);
             db.SaveChanges();
+
+            // Remove from the cache
+            lock (_cacheLock)
+            {
+                _pasteCache.DeleteObject(url);
+            }
+        }
+
+        public static void ModifyPaste(TeknikEntities db, Models.Paste paste)
+        {
+            // Update the cache's copy
+            lock (_cacheLock)
+            {
+                _pasteCache.UpdateObject(paste.Url, paste);
+            }
+
+            if (!db.Exists(paste))
+                db.Attach(paste);
+
+            // Update the database
+            db.Entry(paste).State = EntityState.Modified;
+            db.SaveChanges();
         }
     }
 }

Teknik/Areas/Upload/Controllers/UploadController.cs

@@ -32,13 +32,10 @@ namespace Teknik.Areas.Upload.Controllers
     [Area("Upload")]
     public class UploadController : DefaultController
     {
-        private const int _cacheLength = 300;
-        private readonly ObjectCache _uploadCache;
         private readonly IBackgroundTaskQueue _queue;
 
         public UploadController(ILogger<Logger> logger, Config config, TeknikEntities dbContext, IBackgroundTaskQueue queue) : base(logger, config, dbContext) 
         {
-            _uploadCache = new ObjectCache(_cacheLength);
             _queue = queue;
         }
         

Teknik/Areas/Upload/UploadHelper.cs

@@ -156,7 +156,7 @@ namespace Teknik.Areas.Upload
 
                 using (TeknikEntities db = new TeknikEntities(optionsBuilder.Options))
                 {
-                    var upload = db.Uploads.FirstOrDefault(up => up.Url == url);
+                    var upload = GetUpload(db, url);
                     if (upload != null)
                     {
                         upload.Downloads++;
@@ -170,13 +170,18 @@ namespace Teknik.Areas.Upload
         {
             lock (_cacheLock)
             {
-                return _uploadCache.GetObject(url, (key) => db.Uploads.FirstOrDefault(up => up.Url == key));
+                var upload = _uploadCache.GetObject(url, (key) => db.Uploads.FirstOrDefault(up => up.Url == key));
+
+                if (!db.Exists(upload))
+                    db.Attach(upload);
+
+                return upload;
             }
         }
 
         public static void DeleteFile(TeknikEntities db, Config config, ILogger<Logger> logger, string url)
         {
-            var upload = db.Uploads.FirstOrDefault(up => up.Url == url);
+            var upload = GetUpload(db, url);
             try
             {
                 var storageService = StorageServiceFactory.GetStorageService(config.UploadConfig.StorageConfig);
@@ -187,15 +192,15 @@ namespace Teknik.Areas.Upload
                 logger.LogError(ex, "Unable to delete file: {0}", upload.FileName);
             }
 
-            // Remove from the cache
-            lock (_cacheLock)
-            {
-                _uploadCache.DeleteObject(upload.FileName);
-            }
-
             // Delete from the DB
             db.Uploads.Remove(upload);
             db.SaveChanges();
+
+            // Remove from the cache
+            lock (_cacheLock)
+            {
+                _uploadCache.DeleteObject(url);
+            }
         }
 
         public static void ModifyUpload(TeknikEntities db, Models.Upload upload)

Teknik/Areas/User/Controllers/UserController.cs

@@ -1435,7 +1435,7 @@ namespace Teknik.Areas.Users.Controllers
                     uploadController.ControllerContext = context;
                     return uploadController.Delete(id);
                 case "paste":
-                    var pasteController = new Paste.Controllers.PasteController(_logger, _config, _dbContext);
+                    var pasteController = new Paste.Controllers.PasteController(_logger, _config, _dbContext, queue);
                     pasteController.ControllerContext = context;
                     return pasteController.Delete(id);
                 case "shortenedUrl":

Teknik/Data/TeknikEntities.cs

@@ -165,5 +165,10 @@ namespace Teknik.Data
 
             base.OnModelCreating(modelBuilder);
         }
+
+        public bool Exists<T>(T entity) where T : class
+        {
+            return this.Set<T>().Local.Any(e => e == entity);
+        }
     }
 }

Utilities/ObjectCache.cs

@@ -23,35 +23,40 @@ namespace Teknik.Utilities
             if (objectCache.TryGetValue(key, out var result) &&
                 result.Item1 > cacheDate.Subtract(new TimeSpan(0, 0, _cacheSeconds)))
             {
-                cacheDate = result.Item1;
+                return (T)result.Item2;
-                foundObject = (T)result.Item2;
             }
             else
             {
                 foundObject = getObjectFunc(key);
+                // Update the cache for this key
+                if (foundObject != null)
+                    UpdateObject(key, foundObject, cacheDate);
             }
 
-            if (foundObject != null)
-                objectCache[key] = new Tuple<DateTime, object>(cacheDate, foundObject);
-
             return foundObject;
         }
 
         public void UpdateObject<T>(string key, T update)
         {
-            var cacheDate = DateTime.UtcNow;
+            UpdateObject(key, update, DateTime.UtcNow);
-            if (objectCache.TryGetValue(key, out var result))
+        }
-            {
+
-                if (result.Item1 <= cacheDate.Subtract(new TimeSpan(0, 0, _cacheSeconds)))
+        public void UpdateObject<T>(string key, T update, DateTime cacheTime)
-                    DeleteObject(key);
+        {
-                else
+            objectCache[key] = new Tuple<DateTime, object>(cacheTime, update);
-                    objectCache[key] = new Tuple<DateTime, object>(result.Item1, update);
-            }
         }
 
         public void DeleteObject(string key)
         {
             objectCache.Remove(key);
         }
+
+        public bool CacheValid(string key)
+        {
+            if (objectCache.TryGetValue(key, out var result) && 
+                result.Item1 > DateTime.UtcNow.Subtract(new TimeSpan(0, 0, _cacheSeconds)))
+                return true;
+            return false;
+        }
     }
 }