in dev environments, override the file provider to use a fallback ima…

…ge for certain paths (#2062)

TASVideos/Extensions/ApplicationBuilderExtensions.cs

@@ -35,13 +35,20 @@ public static IApplicationBuilder UseGzipCompression(this IApplicationBuilder ap
 
 	public static IApplicationBuilder UseStaticFilesWithExtensionMapping(this IApplicationBuilder app, IWebHostEnvironment env)
 	{
-		var provider = new FileExtensionContentTypeProvider();
-		return app.UseStaticFiles(new StaticFileOptions
+		var contentTypeProvider = new FileExtensionContentTypeProvider();
+		var staticFileOptions = new StaticFileOptions
 		{
-			ContentTypeProvider = provider,
+			ContentTypeProvider = contentTypeProvider,
 			ServeUnknownFileTypes = true,
 			DefaultContentType = "text/plain"
-		});
+		};
+
+		if (env.IsDevelopment())
+		{
+			staticFileOptions.FileProvider = new DevFallbackFileProvider(env.WebRootFileProvider);
+		}
+
+		return app.UseStaticFiles(staticFileOptions);
 	}
 
 	public static IApplicationBuilder UseMvcWithOptions(this IApplicationBuilder app, IHostEnvironment env, AppSettings settings)

TASVideos/Services/DevFallbackFileProvider.cs

@@ -0,0 +1,28 @@
+using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Primitives;
+
+namespace TASVideos.Services;
+
+public class DevFallbackFileProvider(IFileProvider originalProvider) : IFileProvider
+{
+	public IDirectoryContents GetDirectoryContents(string subpath)
+	{
+		return originalProvider.GetDirectoryContents(subpath);
+	}
+
+	public IFileInfo GetFileInfo(string subpath)
+	{
+		IFileInfo fileInfo = originalProvider.GetFileInfo(subpath);
+		if (!fileInfo.Exists && subpath.StartsWith("/media/"))
+		{
+			return originalProvider.GetFileInfo("/images/tasvideos_rss.png");
+		}
+
+		return fileInfo;
+	}
+
+	public IChangeToken Watch(string filter)
+	{
+		return originalProvider.Watch(filter);
+	}
+}