Add Wkhtmltoimage support

Rotativa.AspNetCore/AsImageResultBase.cs

@@ -0,0 +1,70 @@
+using Microsoft.AspNetCore.Mvc;
+using Rotativa.AspNetCore.Options;
+
+namespace Rotativa.AspNetCore
+{
+    public abstract class AsImageResultBase : AsResultBase
+    {
+        /// <summary>
+        /// Set height for cropping
+        /// </summary>
+        [OptionFlag("-f")]
+        public ImageFormat? Format { get; set; }
+
+        /// <summary>
+        /// Output image quality (between 0 and 100) (default 94)
+        /// </summary>
+        [OptionFlag("--quality")]
+        public int? Quality { get; set; }
+
+        /// <summary>
+        /// Set height for cropping
+        /// </summary>
+        [OptionFlag("--crop-h")]
+        public int? CropHeight { get; set; }
+
+        /// <summary>
+        /// Set width for cropping
+        /// </summary>
+        [OptionFlag("--crop-w")]
+        public int? CropWidth { get; set; }
+
+        /// <summary>
+        /// Set x coordinate for cropping
+        /// </summary>
+        [OptionFlag("--crop-x")]
+        public int? CropX { get; set; }
+
+        /// <summary>
+        /// Set y coordinate for cropping
+        /// </summary>
+        [OptionFlag("--crop-y")]
+        public int? CropY { get; set; }
+
+        /// <summary>
+        /// Sets the page width.
+        /// </summary>
+        /// <remarks>Set screen width, note that this is used only as a guide line.</remarks>
+        [OptionFlag("--width")]
+        public int? PageWidth { get; set; }
+
+        /// <summary>
+        /// Sets the page height in mm.
+        /// </summary>
+        /// <remarks>Has priority over <see cref="PageSize"/> but <see cref="PageWidth"/> has to be also specified.</remarks>
+        [OptionFlag("--height")]
+        public int? PageHeight { get; set; }
+
+        protected override byte[] WkhtmlConvert(string switches)
+        {
+            return WkhtmltoimageDriver.Convert(this.WkhtmlPath, switches);
+        }
+
+        protected override string GetContentType()
+        {
+            var imageFormat = this.Format ?? ImageFormat.jpeg;
+
+            return $"image/{imageFormat}";
+        }
+    }
+}

Rotativa.AspNetCore/ViewAsImage.cs

@@ -0,0 +1,151 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.ModelBinding;
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Mvc.ViewEngines;
+using Microsoft.AspNetCore.Mvc.ViewFeatures;
+
+namespace Rotativa.AspNetCore
+{
+    public class ViewAsImage : AsImageResultBase
+    {
+        private string _viewName;
+
+        public string ViewName
+        {
+            get => _viewName ?? string.Empty;
+            set => _viewName = value;
+        }
+
+        private string _masterName;
+
+        public string MasterName
+        {
+            get => _masterName ?? string.Empty;
+            set => _masterName = value;
+        }
+
+        public object Model { get; set; }
+
+        public ViewDataDictionary ViewData { get; set; }
+
+        public ViewAsImage(ViewDataDictionary viewData = null)
+        {
+            this.WkhtmlPath = string.Empty;
+            MasterName = string.Empty;
+            ViewName = string.Empty;
+            Model = null;
+            ViewData = viewData;
+        }
+
+        public ViewAsImage(string viewName, ViewDataDictionary viewData = null)
+            : this(viewData)
+        {
+            ViewName = viewName;
+        }
+
+        public ViewAsImage(object model, ViewDataDictionary viewData = null)
+            : this(viewData)
+        {
+            Model = model;
+        }
+
+        public ViewAsImage(string viewName, object model, ViewDataDictionary viewData = null)
+            : this(viewData)
+        {
+            ViewName = viewName;
+            Model = model;
+        }
+
+        public ViewAsImage(string viewName, string masterName, object model)
+            : this(viewName, model)
+        {
+            MasterName = masterName;
+        }
+
+        protected override string GetUrl(ActionContext context)
+        {
+            return string.Empty;
+        }
+
+        protected virtual ViewEngineResult GetView(ActionContext context, string viewName, string masterName)
+        {
+            var engine = context.HttpContext.RequestServices.GetService(typeof(ICompositeViewEngine)) as ICompositeViewEngine;
+            var getViewResult = engine.GetView(executingFilePath: null, viewPath: viewName, isMainPage: true);
+            if (getViewResult.Success)
+            {
+                return getViewResult;
+            }
+
+            var findViewResult = engine.FindView(context, viewName, isMainPage: true);
+            if (findViewResult.Success)
+            {
+                return findViewResult;
+            }
+
+            var searchedLocations = getViewResult.SearchedLocations.Concat(findViewResult.SearchedLocations);
+            var errorMessage = string.Join(
+                Environment.NewLine,
+                new[] { $"Unable to find view '{viewName}'. The following locations were searched:" }.Concat(searchedLocations));
+
+            throw new InvalidOperationException(errorMessage);
+        }
+
+        protected override async Task<byte[]> CallTheDriver(ActionContext context)
+        {
+            // use action name if the view name was not provided
+            string viewName = ViewName;
+            if (string.IsNullOrEmpty(ViewName))
+            {
+                viewName = ((Microsoft.AspNetCore.Mvc.Controllers.ControllerActionDescriptor)context.ActionDescriptor).ActionName;
+            }
+
+            ViewEngineResult viewResult = GetView(context, viewName, MasterName);
+            var html = new StringBuilder();
+
+            //string html = context.GetHtmlFromView(viewResult, viewName, Model);
+            ITempDataProvider tempDataProvider = context.HttpContext.RequestServices.GetService(typeof(ITempDataProvider)) as ITempDataProvider;
+
+            var viewDataDictionary = new ViewDataDictionary(
+                metadataProvider: new EmptyModelMetadataProvider(),
+                modelState: new ModelStateDictionary())
+            {
+                Model = this.Model
+            };
+            if (this.ViewData != null)
+            {
+                foreach (var item in this.ViewData)
+                {
+                    viewDataDictionary.Add(item);
+                }
+            }
+            using (var output = new StringWriter())
+            {
+                var view = viewResult.View;
+                var tempDataDictionary = new TempDataDictionary(context.HttpContext, tempDataProvider);
+                var viewContext = new ViewContext(
+                    context,
+                    viewResult.View,
+                    viewDataDictionary,
+                    tempDataDictionary,
+                    output,
+                    new HtmlHelperOptions());
+
+                await view.RenderAsync(viewContext);
+
+                html = output.GetStringBuilder();
+            }
+
+            string baseUrl = $"{context.HttpContext.Request.Scheme}://{context.HttpContext.Request.Host}";
+            var htmlForWkhtml = Regex.Replace(html.ToString(), "<head>", $"<head><base href=\"{baseUrl}\" />", RegexOptions.IgnoreCase);
+
+            byte[] fileContent = WkhtmltoimageDriver.ConvertHtml(this.WkhtmlPath, this.GetConvertOptions(), htmlForWkhtml);
+            return fileContent;
+        }
+    }
+}

Rotativa.AspNetCore/WkhtmltoimageDriver.cs

@@ -0,0 +1,36 @@
+using System.Runtime.InteropServices;
+
+namespace Rotativa.AspNetCore
+{
+    public class WkhtmltoimageDriver : WkhtmlDriver
+    {
+        /// <summary>
+        /// wkhtmltoimage only has a .exe extension in Windows.
+        /// </summary>
+        private static readonly string wkhtmlExe =
+            RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ? "wkhtmltoimage.exe" : "wkhtmltoimage";
+
+        /// <summary>
+        /// Converts given HTML string to Image.
+        /// </summary>
+        /// <param name="wkhtmltoimagePath">Path to wkthmltoimage.</param>
+        /// <param name="switches">Switches that will be passed to wkhtmltoimage binary.</param>
+        /// <param name="html">String containing HTML code that should be converted to Image.</param>
+        /// <returns>PDF as byte array.</returns>
+        public static byte[] ConvertHtml(string wkhtmltoimagePath, string switches, string html)
+        {
+            return Convert(wkhtmltoimagePath, switches, html, wkhtmlExe);
+        }
+
+        /// <summary>
+        /// Converts given URL to Image.
+        /// </summary>
+        /// <param name="wkhtmltoimagePath">Path to wkthmltoimage.</param>
+        /// <param name="switches">Switches that will be passed to wkhtmltoimage binary.</param>
+        /// <returns>PDF as byte array.</returns>
+        public static byte[] Convert(string wkhtmltoimagePath, string switches)
+        {
+            return Convert(wkhtmltoimagePath, switches, null, wkhtmlExe);
+        }
+    }
+}