Fixes two bugs in deserializing DateTime objects from strings.

Doug Schmidt · Doug Schmidt · commit 2dbc177f5cb7 · 2013-10-28T09:29:43.000-07:00
1) Long-form dates "yyyy-MM-ddTHH:mm:ss.fffffffZ" are now correctedly parsed with Kind=Utc Previously, only short-form dates (no trailing ".ffff" milliseconds) were parsed as Kind=Utc. Long-form were parsed as Kind=Local 2) Added RepairXsdTimeSeparator() method to work around a bug in System.Data.SQLite v1.0.88, which sometimes uses a space instead of the 'T' separator between the time and date. Obligatory XKCD reference: http://xkcd.com/1179/
diff --git a/src/ServiceStack.Text/Common/DateTimeSerializer.cs b/src/ServiceStack.Text/Common/DateTimeSerializer.cs
@@ -37,6 +37,10 @@ public static class DateTimeSerializer
         public const string UnspecifiedOffset = "-0000";
         public const string UtcOffset = "+0000";
 
+        private const char XsdTimeSeparator = 'T';
+        private static readonly int XsdTimeSeparatorIndex = XsdDateTimeFormat.IndexOf(XsdTimeSeparator);
+        private const string XsdUtcSuffix = "Z";
+
         /// <summary>
         /// If AlwaysUseUtc is set to true then convert all DateTime to UTC.
         /// </summary>
@@ -73,12 +77,14 @@ public static DateTime ParseShortestXsdDateTime(string dateTimeStr)
                 return DateTime.Parse(dateTimeStr, CultureInfo.InvariantCulture).Prepare();
             }
 
+            dateTimeStr = RepairXsdTimeSeparator(dateTimeStr);
+
             if (dateTimeStr.Length == XsdDateTimeFormatSeconds.Length)
                 return DateTime.ParseExact(dateTimeStr, XsdDateTimeFormatSeconds, null, DateTimeStyles.AdjustToUniversal).Prepare(parsedAsUtc:true); 
 
             if (dateTimeStr.Length >= XsdDateTimeFormat3F.Length
                 && dateTimeStr.Length <= XsdDateTimeFormat.Length
-                && dateTimeStr.EndsWith("Z"))
+                && dateTimeStr.EndsWith(XsdUtcSuffix))
             {
 #if NETFX_CORE
                 var dateTimeType = JsConfig.DateHandler != JsonDateHandler.ISO8601
@@ -91,7 +97,7 @@ public static DateTime ParseShortestXsdDateTime(string dateTimeStr)
                 if (dateTime != null)
                     return dateTime.Value;
 
-                return XmlConvert.ToDateTime(dateTimeStr, XmlDateTimeSerializationMode.Utc).Prepare();
+                return XmlConvert.ToDateTime(dateTimeStr, XmlDateTimeSerializationMode.Utc).Prepare(parsedAsUtc:true);
 #endif
             }
 
@@ -109,13 +115,30 @@ public static DateTime ParseShortestXsdDateTime(string dateTimeStr)
             }
         }
 
+        /// <summary>
+        /// Repairs an out-of-spec XML date/time string which incorrectly uses a space instead of a 'T' to separate the date from the time.
+        /// These string are occasionally generated by SQLite and can cause errors in OrmLite when reading these columns from the DB.
+        /// </summary>
+        /// <param name="dateTimeStr">The XML date/time string to repair</param>
+        /// <returns>The repaired string. If no repairs were made, the original string is returned.</returns>
+        private static string RepairXsdTimeSeparator(string dateTimeStr)
+        {
+            if( (dateTimeStr.Length > XsdTimeSeparatorIndex) && (dateTimeStr[XsdTimeSeparatorIndex] == ' ') && dateTimeStr.EndsWith(XsdUtcSuffix) )
+            {
+                dateTimeStr = dateTimeStr.Substring(0, XsdTimeSeparatorIndex) + XsdTimeSeparator +
+                              dateTimeStr.Substring(XsdTimeSeparatorIndex + 1);
+            }
+
+            return dateTimeStr;
+        }
+
         public static DateTime? ParseManual(string dateTimeStr)
         {
             if (dateTimeStr == null || dateTimeStr.Length < "YYYY-MM-DD".Length)
                 return null;
 
             var dateKind = DateTimeKind.Utc;
-            if (dateTimeStr.EndsWith("Z"))
+            if (dateTimeStr.EndsWith(XsdUtcSuffix))
             {
                 dateTimeStr = dateTimeStr.Substring(0, dateTimeStr.Length - 1);
             }
@@ -224,7 +247,7 @@ public static DateTimeOffset ParseDateTimeOffset(string dateTimeOffsetStr)
             // assume utc when no offset specified
             if (dateTimeOffsetStr.LastIndexOfAny(TimeZoneChars) < 10)
             {
-                if (!dateTimeOffsetStr.EndsWith("Z")) dateTimeOffsetStr += "Z";
+                if (!dateTimeOffsetStr.EndsWith(XsdUtcSuffix)) dateTimeOffsetStr += XsdUtcSuffix;
 #if __MonoCS__
                 // Without that Mono uses a Local timezone))
                 dateTimeOffsetStr = dateTimeOffsetStr.Substring(0, dateTimeOffsetStr.Length - 1) + "+00:00"; 
@@ -267,6 +290,8 @@ public static string ToXsdTimeSpanString(TimeSpan? timeSpan)
 
         public static DateTime ParseXsdDateTime(string dateTimeStr)
         {
+            dateTimeStr = RepairXsdTimeSeparator(dateTimeStr);
+
 #if NETFX_CORE
             return XmlConvert.ToDateTimeOffset(dateTimeStr).DateTime;
 #else
diff --git a/tests/ServiceStack.Text.Tests/Utils/DateTimeSerializerTests.cs b/tests/ServiceStack.Text.Tests/Utils/DateTimeSerializerTests.cs
@@ -147,6 +147,43 @@ public void UtcDateTime_Is_Deserialized_As_Kind_Utc()
 			Assert.That(deserialized.Kind, Is.EqualTo(DateTimeKind.Utc)); //fails -> is DateTimeKind.Local
 		}
 
+        /// <summary>
+        /// These timestamp strings were pulled from SQLite columns written via OrmLite using SQlite.1.88
+        /// Most of the time, timestamps correctly use the 'T' separator between the date and time,
+        /// but under some (still unknown) scnearios, SQLite will write timestamps using a space instead of a 'T'.
+        /// If that happens, OrmLite will fail to read the row, complaining that: The string '...' is not a valid Xsd value.
+        /// </summary>
+	    private static string[] _problematicXsdStrings = new[] {
+	        "2013-10-10 20:04:04.8773249Z",
+            "2013-10-10 20:04:04Z",
+	    };
+
+        [Test]
+        [TestCase(0)]
+        [TestCase(1)]
+        public void CanParseProblematicXsdStrings(int whichString)
+        {
+            var xsdString = _problematicXsdStrings[whichString];
+
+            var dateTime = DateTimeSerializer.ParseShortestXsdDateTime(xsdString);
+
+            Assert.That(dateTime.Kind, Is.EqualTo(DateTimeKind.Local));
+        }
+
+        [Test]
+        public void CanParseLongAndShortXsdStrings()
+        {
+            var shortXsdString = "2013-10-10T13:40:50Z";
+            var longXsdString = shortXsdString.Substring(0, shortXsdString.Length - 1) + ".0000000" +
+                                shortXsdString.Substring(shortXsdString.Length - 1);
+
+            var dateTimeShort = DateTimeSerializer.ParseShortestXsdDateTime(shortXsdString);
+            var dateTimeLong = DateTimeSerializer.ParseShortestXsdDateTime(longXsdString);
+
+            Assert.That(dateTimeShort.Ticks, Is.EqualTo(dateTimeLong.Ticks));
+            Assert.That(dateTimeShort.Kind, Is.EqualTo(dateTimeLong.Kind));
+        }
+
         private static DateTime[] _dateTimeTests = new[] {
 			DateTime.Now,
 			DateTime.UtcNow,
