Fix deserialization with missing XML namespace (#1327)

* Fix deserialization with missing XML namespace

* Adjust formatting

---------

Co-authored-by: ebozduman <ersan.bozduman@gmail.com>

Author: BaerMitUmlaut

Minio.Tests/UtilsTest.cs

@@ -18,6 +18,7 @@
 using System.Xml.Serialization;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using Minio.DataModel;
+using Minio.DataModel.Result;
 using Minio.Exceptions;
 using Minio.Helper;
 
@@ -235,4 +236,23 @@ public void TestisValidEndpoint()
         Assert.IsTrue(RequestUtil.IsValidEndpoint("A.domain.com"));
         Assert.IsTrue(RequestUtil.IsValidEndpoint("A.domain1.com"));
     }
+
+    [TestMethod]
+    public void TestXmlResultWithoutNamespace()
+    {
+        var xml =
+            """
+            <?xml version="1.0" encoding="UTF-8"?>
+            <CopyObjectResult>
+                <LastModified>
+                    2022-10-29T15:34:41.626Z
+                </LastModified>
+                <ETag>
+                    &#34;ead3fcd881dee32547f1b6ca1fc29463&#34;
+                </ETag>
+            </CopyObjectResult>
+            """;
+        var result = Utils.DeserializeXml<CopyObjectResult>(xml);
+        Assert.IsNotNull(result);
+    }
 }

Minio/Helper/AmazonAwsS3XmlReader.cs

@@ -24,5 +24,9 @@ public AmazonAwsS3XmlReader(Stream stream) : base(stream)
     {
     }
 
+    public AmazonAwsS3XmlReader(TextReader textReader) : base(textReader)
+    {
+    }
+
     public override string NamespaceURI => "http://s3.amazonaws.com/doc/2006-03-01/";
 }

Minio/Helper/Utils.cs

@@ -1050,13 +1050,29 @@ public static string SerializeToXml<T>(T anyobject) where T : class
         using var reader = new StreamReader(stream);
         var xmlContent = reader.ReadToEnd();
 
-        return DeserializeXml<T>(xmlContent); // Call the string overload
+        return DeserializeNonS3Xml<T>(xmlContent); // Fallback to generic XML deserialization
     }
 
     public static T DeserializeXml<T>(string xml) where T : class, new()
     {
         if (string.IsNullOrEmpty(xml)) return default;
 
+        var ns = GetNamespace<T>();
+        if (!string.IsNullOrWhiteSpace(ns) && string.Equals(ns, "http://s3.amazonaws.com/doc/2006-03-01/",
+                StringComparison.OrdinalIgnoreCase))
+        {
+            using var stringReader = new StringReader(xml);
+            using var amazonAwsS3XmlReader = new AmazonAwsS3XmlReader(stringReader);
+            return (T)new XmlSerializer(typeof(T)).Deserialize(amazonAwsS3XmlReader);
+        }
+
+        return DeserializeNonS3Xml<T>(xml); // Fallback to generic XML deserialization
+    }
+
+    private static T DeserializeNonS3Xml<T>(string xml) where T : class, new()
+    {
+        if (string.IsNullOrEmpty(xml)) return default;
+
         var settings = new XmlReaderSettings
         {
             // Disable DTD processing