v10: Update to ImageSharp v2 (#12185)

* Update to ImageSharp 2.1.0 and ImageSharp.Web 2.0.0-alpha.0.23

* Rename CachedNameLength to CacheHashLength and add CacheFolderDepth setting

* Replace PhysicalFileSystemProvider with WebRootImageProvider

* Support EXIF-orientation in image dimention extractor

* Remove virtual methods on FileProviderImageProvider

* Simplify FileInfoImageResolver

* Update to SixLabors.ImageSharp.Web 2.0.0-alpha.0.25 and remove custom providers

* Make CropWebProcessor EXIF orientation-aware

* Improve width/height sanitization

* Also use 'v' as cache buster value

* Add WebP to supported image file types

* Update to SixLabors.ImageSharp.Web 2.0.0-alpha.0.27 and fix test

* Fix rounding error and add test cases

* Update to newest and stable releases

* Move ImageSharpImageUrlGenerator to Umbraco.Web.Common

* Use IConfigureOptions to configure ImageSharp options

* Implement IEquatable on ImageUrlGenerationOptions classes

* Fix empty/null values in image URL generation and corresponding tests

* Use IsSupportedImageFormat extension method

* Remove unneeded reflection

src/Umbraco.Web.Common/DependencyInjection/ConfigureImageSharpMiddlewareOptions.cs

@@ -0,0 +1,88 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.Headers;
+using Microsoft.Extensions.Options;
+using Microsoft.Net.Http.Headers;
+using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.Web.Commands;
+using SixLabors.ImageSharp.Web.Middleware;
+using SixLabors.ImageSharp.Web.Processors;
+using Umbraco.Cms.Core.Configuration.Models;
+
+namespace Umbraco.Cms.Web.Common.DependencyInjection
+{
+    /// <summary>
+    /// Configures the ImageSharp middleware options.
+    /// </summary>
+    /// <seealso cref="IConfigureOptions{ImageSharpMiddlewareOptions}" />
+    public sealed class ConfigureImageSharpMiddlewareOptions : IConfigureOptions<ImageSharpMiddlewareOptions>
+    {
+        private readonly Configuration _configuration;
+        private readonly ImagingSettings _imagingSettings;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ConfigureImageSharpMiddlewareOptions" /> class.
+        /// </summary>
+        /// <param name="configuration">The ImageSharp configuration.</param>
+        /// <param name="imagingSettings">The Umbraco imaging settings.</param>
+        public ConfigureImageSharpMiddlewareOptions(Configuration configuration, IOptions<ImagingSettings> imagingSettings)
+        {
+            _configuration = configuration;
+            _imagingSettings = imagingSettings.Value;
+        }
+
+        /// <inheritdoc />
+        public void Configure(ImageSharpMiddlewareOptions options)
+        {
+            options.Configuration = _configuration;
+
+            options.BrowserMaxAge = _imagingSettings.Cache.BrowserMaxAge;
+            options.CacheMaxAge = _imagingSettings.Cache.CacheMaxAge;
+            options.CacheHashLength = _imagingSettings.Cache.CacheHashLength;
+
+            // Use configurable maximum width and height
+            options.OnParseCommandsAsync = context =>
+            {
+                if (context.Commands.Count == 0)
+                {
+                    return Task.CompletedTask;
+                }
+
+                int width = context.Parser.ParseValue<int>(context.Commands.GetValueOrDefault(ResizeWebProcessor.Width), context.Culture);
+                if (width <= 0 || width > _imagingSettings.Resize.MaxWidth)
+                {
+                    context.Commands.Remove(ResizeWebProcessor.Width);
+                }
+
+                int height = context.Parser.ParseValue<int>(context.Commands.GetValueOrDefault(ResizeWebProcessor.Height), context.Culture);
+                if (height <= 0 || height > _imagingSettings.Resize.MaxHeight)
+                {
+                    context.Commands.Remove(ResizeWebProcessor.Height);
+                }
+
+                return Task.CompletedTask;
+            };
+
+            // Change Cache-Control header when cache buster value is present
+            options.OnPrepareResponseAsync = context =>
+            {
+                if (context.Request.Query.ContainsKey("rnd") || context.Request.Query.ContainsKey("v"))
+                {
+                    ResponseHeaders headers = context.Response.GetTypedHeaders();
+
+                    CacheControlHeaderValue cacheControl = headers.CacheControl ?? new CacheControlHeaderValue()
+                    {
+                        Public = true
+                    };
+                    cacheControl.MustRevalidate = false; // ImageSharp enables this by default
+                    cacheControl.Extensions.Add(new NameValueHeaderValue("immutable"));
+
+                    headers.CacheControl = cacheControl;
+                }
+
+                return Task.CompletedTask;
+            };
+        }
+    }
+}