UI now loads the 250px image if available, and reverts to full size otherwise.

src/NzbDrone.Api/Frontend/Mappers/MediaCoverMapper.cs

@@ -1,4 +1,6 @@
 using System.IO;
+using System.Text.RegularExpressions;
+using Nancy;
 using NLog;
 using NzbDrone.Common.Disk;
 using NzbDrone.Common.EnvironmentInfo;
@@ -8,6 +10,8 @@ namespace NzbDrone.Api.Frontend.Mappers
 {
     public class MediaCoverMapper : StaticResourceMapperBase
     {
+        private static readonly Regex RegexResizedImage = new Regex(@"-\d+\.jpg($|\?)", RegexOptions.Compiled | RegexOptions.IgnoreCase);
+
         private readonly IAppFolderInfo _appFolderInfo;
 
         public MediaCoverMapper(IAppFolderInfo appFolderInfo, IDiskProvider diskProvider, Logger logger)
@@ -24,6 +28,24 @@ namespace NzbDrone.Api.Frontend.Mappers
             return Path.Combine(_appFolderInfo.GetAppDataPath(), path);
         }
 
+        public override Response GetResponse(string resourceUrl)
+        {
+            var result =  base.GetResponse(resourceUrl);
+
+            // Return the full sized image if someone requests a non-existing resized one.
+            // TODO: This code can be removed later once everyone had the update for a while.
+            if (result is NotFoundResponse)
+            {
+                var baseResourceUrl = RegexResizedImage.Replace(resourceUrl, ".jpg$1");
+                if (baseResourceUrl != resourceUrl)
+                {
+                    result = base.GetResponse(baseResourceUrl);
+                }
+            }
+
+            return result;
+        }
+
         public override bool CanHandle(string resourceUrl)
         {
             return resourceUrl.StartsWith("/MediaCover");

src/NzbDrone.Api/MediaCovers/MediaCoverModule.cs

@@ -1,4 +1,5 @@
 using System.IO;
+using System.Text.RegularExpressions;
 using Nancy;
 using Nancy.Responses;
 using NzbDrone.Common.Disk;
@@ -9,6 +10,8 @@ namespace NzbDrone.Api.MediaCovers
 {
     public class MediaCoverModule : NzbDroneApiModule
     {
+        private static readonly Regex RegexResizedImage = new Regex(@"-\d+\.jpg$", RegexOptions.Compiled | RegexOptions.IgnoreCase);
+
         private const string MEDIA_COVER_ROUTE = @"/(?<seriesId>\d+)/(?<filename>(.+)\.(jpg|png|gif))";
 
         private readonly IAppFolderInfo _appFolderInfo;
@@ -27,7 +30,16 @@ namespace NzbDrone.Api.MediaCovers
             var filePath = Path.Combine(_appFolderInfo.GetAppDataPath(), "MediaCover", seriesId.ToString(), filename);
 
             if (!_diskProvider.FileExists(filePath))
+            {
+                // Return the full sized image if someone requests a non-existing resized one.
+                // TODO: This code can be removed later once everyone had the update for a while.
+                var basefilePath = RegexResizedImage.Replace(filePath, ".jpg");
+                if (basefilePath == filePath || !_diskProvider.FileExists(basefilePath))
+                {
                     return new NotFoundResponse();
+                }
+                filePath = basefilePath;
+            }
 
             return new StreamResponse(() => File.OpenRead(filePath), MimeTypes.GetMimeType(filePath));
         }

src/UI/Handlebars/Helpers/Html.js

@@ -17,8 +17,16 @@ define(
             img.onerror = null;
         };
 
-        Handlebars.registerHelper('defaultImg', function () {
-            return new Handlebars.SafeString('onerror=window.NzbDrone.imageError(this)');
+        Handlebars.registerHelper('defaultImg', function (src, size) {
+            if (!src) {
+                return new Handlebars.SafeString('onerror="window.NzbDrone.imageError(this);"');
+            }
+
+            if (size) {
+                src = src.replace(/\.jpg($|\?)/g, '-' + size + '.jpg$1');
+            }
+
+            return new Handlebars.SafeString('src="{0}" onerror="window.NzbDrone.imageError(this);"'.format(src));
         });
 
         Handlebars.registerHelper('UrlBase', function () {

src/UI/Handlebars/Helpers/Series.js

@@ -11,7 +11,7 @@ define(
             var poster = _.where(this.images, {coverType: 'poster'});
 
             if (poster[0]) {
-                return new Handlebars.SafeString('<img class="series-poster" src="{0}" {1}>'.format(poster[0].url, Handlebars.helpers.defaultImg.call()));
+                return new Handlebars.SafeString('<img class="series-poster" {0}>'.format(Handlebars.helpers.defaultImg.call(null, poster[0].url, 250)));
             }
 
             return new Handlebars.SafeString('<img class="series-poster placeholder-image" src="{0}">'.format(placeholder));