Lots of work for validation. We have a different type of validation model in Umbraco where we still save content even if some things are invalid (we just don't publish) so we have to take all of this into account. We also have other rules where if it is new content but required fields like 'name' are empty we cannot continue to save. Also started working on dealing with server side validation errors for content fields (not just user defined fields).

src/Umbraco.Core/StringExtensions.cs

@@ -28,6 +28,21 @@ namespace Umbraco.Core
         [UmbracoWillObsolete("Do not use this constants. See IShortStringHelper.CleanStringForSafeAliasJavaScriptCode.")]
         public const string UmbracoInvalidFirstCharacters = "01234567890";
 
+        /// <summary>
+        /// Returns a stream from a string
+        /// </summary>
+        /// <param name="s"></param>
+        /// <returns></returns>
+        internal static Stream GenerateStreamFromString(this string s)
+        {
+            var stream = new MemoryStream();
+            var writer = new StreamWriter(stream);
+            writer.Write(s);
+            writer.Flush();
+            stream.Position = 0;
+            return stream;
+        }
+
         /// <summary>
         /// This will append the query string to the URL
         /// </summary>