Fixing virtual directory mapping issue

Former-commit-id: 1adc402cdb870e1399e0d8c297268371237aafa2

src/ImageProcessor.Web/NET45/Caching/DiskCache.cs

@@ -49,14 +49,14 @@ namespace ImageProcessor.Web.Caching
         private const int MaxFilesCount = 100;
 
         /// <summary>
-        /// The absolute path to virtual cache path on the server.
+        /// The virtual cache path.
         /// </summary>
-        private static readonly string AbsoluteCachePath = HostingEnvironment.MapPath(ImageProcessorConfiguration.Instance.VirtualCachePath);
+        private static readonly string VirtualCachePath = ImageProcessorConfiguration.Instance.VirtualCachePath;
 
         /// <summary>
-        /// The request for the image.
+        /// The absolute path to virtual cache path on the server.
         /// </summary>
-        private readonly HttpRequest request;
+        private static readonly string AbsoluteCachePath = HostingEnvironment.MapPath(ImageProcessorConfiguration.Instance.VirtualCachePath);
 
         /// <summary>
         /// The request path for the image.
@@ -72,15 +72,22 @@ namespace ImageProcessor.Web.Caching
         /// The image name
         /// </summary>
         private readonly string imageName;
+
+        /// <summary>
+        /// The physical cached path.
+        /// </summary>
+        private string physicalCachedPath;
+
+        /// <summary>
+        /// The virtual cached path.
+        /// </summary>
+        private string virtualCachedPath;
         #endregion
 
         #region Constructors
         /// <summary>
         /// Initializes a new instance of the <see cref="DiskCache"/> class.
         /// </summary>
-        /// <param name="request">
-        /// The request for the image.
-        /// </param>
         /// <param name="requestPath">
         /// The request path for the image.
         /// </param>
@@ -90,53 +97,41 @@ namespace ImageProcessor.Web.Caching
         /// <param name="imageName">
         /// The image name.
         /// </param>
-        public DiskCache(HttpRequest request, string requestPath, string fullPath, string imageName)
+        public DiskCache(string requestPath, string fullPath, string imageName)
         {
-            this.request = request;
             this.requestPath = requestPath;
             this.fullPath = fullPath;
             this.imageName = imageName;
+
+            // Get the physical and virtual paths.
+            this.GetCachePaths();
         }
         #endregion
 
-        #region Methods
-        #region Internal
         /// <summary>
-        /// Gets the full transformed cached path for the image. 
-        /// The images are stored in paths that are based upon the SHA1 of their full request path
-        /// taking the individual characters of the hash to determine their location.
-        /// This allows us to store millions of images.
+        /// Gets the cached path.
         /// </summary>
-        /// <returns>The full cached path for the image.</returns>
-        internal Task<string> GetCachePathAsync()
+        public string CachedPath
         {
-            return TaskHelpers.Run<string>(this.GetCachePath);
+            get
+            {
+                return this.physicalCachedPath;
+            }
         }
 
         /// <summary>
-        /// Gets the virtual path to the cached processed image.
+        /// Gets the cached path.
         /// </summary>
-        /// <param name="cachedPath">
-        /// The path to the cached image.
-        /// </param>
-        /// <returns>
-        /// The virtual path to the cached processed image.
-        /// </returns>
-        internal string GetVirtualCachedPath(string cachedPath)
+        public string VirtualCachedPath
         {
-            string applicationPath = this.request.PhysicalApplicationPath;
-            string virtualDir = this.request.ApplicationPath;
-            virtualDir = virtualDir == "/" ? virtualDir : (virtualDir + "/");
-
-            if (applicationPath != null)
+            get
             {
-                return cachedPath.Replace(applicationPath, virtualDir).Replace(@"\", "/");
+                return this.virtualCachedPath;
             }
-
-            throw new InvalidOperationException(
-                "We can only map an absolute back to a relative path if the application path is available.");
         }
 
+        #region Methods
+        #region Internal
         /// <summary>
         /// Adds an image to the cache.
         /// </summary>
@@ -256,15 +251,13 @@ namespace ImageProcessor.Web.Caching
         }
 
         /// <summary>
-        /// Gets the full transformed cached path for the image. 
+        /// Gets the full transformed cached paths for the image. 
         /// The images are stored in paths that are based upon the SHA1 of their full request path
         /// taking the individual characters of the hash to determine their location.
         /// This allows us to store millions of images.
         /// </summary>
-        /// <returns>The full cached path for the image.</returns>
-        private string GetCachePath()
+        private void GetCachePaths()
         {
-            string cachedPath = string.Empty;
             string streamHash = string.Empty;
 
             if (AbsoluteCachePath != null)
@@ -302,16 +295,16 @@ namespace ImageProcessor.Web.Caching
 
                 // Collision rate of about 1 in 10000 for the folder structure.
                 string pathFromKey = string.Join("\\", encryptedName.ToCharArray().Take(6));
+                string virtualPathFromKey = pathFromKey.Replace(@"\", "/");
 
                 string cachedFileName = string.Format(
                     "{0}.{1}",
                     encryptedName,
                     !string.IsNullOrWhiteSpace(parsedExtension) ? parsedExtension.Replace(".", string.Empty) : fallbackExtension);
 
-                cachedPath = Path.Combine(AbsoluteCachePath, pathFromKey, cachedFileName);
+                this.physicalCachedPath = Path.Combine(AbsoluteCachePath, pathFromKey, cachedFileName);
+                this.virtualCachedPath = Path.Combine(VirtualCachePath, virtualPathFromKey, cachedFileName).Replace(@"\", "/");
             }
-
-            return cachedPath;
         }
 
         /// <summary>

src/ImageProcessor.Web/NET45/HttpModules/ImageProcessingModule.cs

@@ -338,15 +338,15 @@ namespace ImageProcessor.Web.HttpModules
                 }
 
                 // Create a new cache to help process and cache the request.
-                DiskCache cache = new DiskCache(request, requestPath, fullPath, imageName);
-                string cachedPath = await cache.GetCachePathAsync();
+                DiskCache cache = new DiskCache(requestPath, fullPath, imageName);
+                string cachedPath = cache.CachedPath;
 
                 // Since we are now rewriting the path we need to check again that the current user has access
                 // to the rewritten path.
                 // Get the user for the current request
                 // If the user is anonymous or authentication doesn't work for this suffix avoid a NullReferenceException 
                 // in the UrlAuthorizationModule by creating a generic identity.
-                string virtualCachedPath = cache.GetVirtualCachedPath(cachedPath);
+                string virtualCachedPath = cache.VirtualCachedPath;
 
                 IPrincipal user = context.User ?? new GenericPrincipal(new GenericIdentity(string.Empty, string.Empty), new string[0]);