Develop Reference

Unable to deserialize list in a XML Response using ReadAsAsync<T>

[Update: This question is different from the suggested duplicate because this one is about deserialization of XML and the explanation of the problem and solution on this one is clearer as I've included the full source code.]
I'm trying to read and subsequently manipulate a response from a Web API. Its response looks like this:
<MYAPI xsi:noNamespaceSchemaLocation="MYAPI.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<MySite Resource="some resource name">
<Name>some name</Name>
<URL>some url</URL>
<SecondName>Describes something</SecondName>
</MySite>
... A lot of these <MySite>...</MySite> are there
<SomeOtherSite Resource="some resource name">
<Name>some name</Name>
<URL>some url</URL>
</SomeOtherSite>
</MYAPI>
SomeOtherSite is not repeating and only one of it appears at the end of the response. But the MySite is the one that is repeating.
I've modeled the class for this XML response as:
public class MYAPI
{
public List<MySite> MySite { get; set; }
public SomeOtherSite SomeOtherSite { get; set; }
}
public class MySite
{
public string Name { get; set; }
public string URL { get; set; }
public string SecondName { get; set; }
}
public class SomeOtherSite
{
public string Name { get; set; }
public string URL { get; set; }
}
And this is my code:
static void Main()
{
var handler = new HttpClientHandler();
handler.Credentials = new NetworkCredential("MyUsername", "MyPassword");
var client = new HttpClient(handler);
client.BaseAddress = new Uri("https://sitename.com:PortNumber/");
var formatters = new List<MediaTypeFormatter>()
{
new XmlMediaTypeFormatter(){ UseXmlSerializer = true }
};
var myApi = new MYAPI();
HttpResponseMessage response = client.GetAsync("/api/mysites").Result;
if (response.IsSuccessStatusCode)
{
myApi = response.Content.ReadAsAsync<MYAPI>(formatters).Result;
}
}
Now the myApi only has object for SomeOtherSite but the list for the MySite is empty.
Would someone please tell me how I should deserialize this response correctly?
Should I be creating custom media formatter? I have no idea of it by the way.
Also would you please tell me how to model that Resource attribute coming in the response?
And I can't change anything in the WebAPI server. I just need to consume the data from it and use it elsewhere.
Thank You so much!

I solved this after some really good direction from: https://stackoverflow.com/users/1124565/amura-cxg Much Thanks!
The solution was to annotate all the properties with XMLAttributes. And it correctly deserialized the response. And as for the Resource attribute, all I needed was [XmlAttribute(AttributeName="Resource")]
The rest of the source code works as is.
[XmlRoot(ElementName="MYAPI")]
public class MYAPI
{
[XmlElement(ElementName="MySite")]
public List<MySite> MySite { get; set; }
[XmlElement(ElementName="SomeOtherSite")]
public SomeOtherSite SomeOtherSite { get; set; }
}
public class MySite
{
[XmlElement(ElementName="Name")]
public string Name { get; set; }
[XmlElement(ElementName="URL")]
public string URL { get; set; }
[XmlElement(ElementName="SecondName")]
public string SecondName { get; set; }
[XmlAttribute(AttributeName="Resource")]
public string Resource { get; set; }
}
Plus, I didn't need any custom media formatter. And from one of the posts by https://stackoverflow.com/users/1855967/elisabeth , I learned that we should not touch the generated file from xsd.exe tool. So I explicitly set to use the XmlSerializer instead of the DataContractSerializer used by default:
var formatters = new List<MediaTypeFormatter>()
{
new XmlMediaTypeFormatter(){ UseXmlSerializer = true }
};

Azure Service-Fabric and DocumentDB message serialization issue

So, - in my DocumentDB I may have the following document:
{
"id": 1,
"type": "A",
"content": {
"x": 1,
"y": 2
}
}
That may be backed by this model:
public class acontent
{
public int x { get; set; }
public int y { get; set; }
}
public class document
{
public int id { get; set; }
public string type { get; set; }
public object content { get; set; }
}
public class documenta : document
{
public new acontent content { get; set; }
}
The idea here is that document is a complex object where content may vary depending on type.
Now, - in my ServiceFabric application I have a stateless microservice that reads from DocumentDB and should return a document type object when called from the ServiceProxy.
The problem in this is that the DocumentQuery from the DocumentDB SDK, uses Json.NET serializer when querying the database, whilst servicefabric uses DataContractSerializer for serializing the service-messages.
So when the content part of document class is being deserialized from the DocumentDB it becomes:
Newtonsoft.Json.Linq.JObject
But when it is serialized back through the returned service-message you get the exception:
Type 'Newtonsoft.Json.Linq.JToken' is a recursive collection data
contract which is not supported. Consider modifying the definition of
collection 'Newtonsoft.Json.Linq.JToken' to remove references to
itself.
To illustrate this issue try the folowing code:
using System;
using System.IO;
using System.Text;
using System.Runtime.Serialization.Json;
using Newtonsoft.Json;
namespace jsoinissue
{
public class acontent
{
public int x { get; set; }
public int y { get; set; }
}
public class document
{
public int id { get; set; }
public string type { get; set; }
public object content { get; set; }
}
public class documenta : document
{
public new acontent content { get; set; }
}
public class Program
{
private const string JSON_A = "{\"id\":1,\"type\":\"A\",\"content\":{\"x\":1,\"y\":2}}";
private static string SerializeObject<T> (T obj)
{
try
{
DataContractJsonSerializer js = new DataContractJsonSerializer(typeof(T));
using (var ms = new MemoryStream())
{
js.WriteObject(ms, obj);
ms.Position = 0;
using (var sr = new StreamReader(ms))
return sr.ReadToEnd();
}
}
catch (Exception e)
{
return String.Format("EXCEPTION: {0}",e.Message);
}
}
public static void Main()
{
var A = JsonConvert.DeserializeObject<document>(JSON_A);
var a = SerializeObject<document>(A);//HERE BE TROUBLE
Console.WriteLine(a);
Console.ReadKey();
}
}
}
How could I best resolve this issue?

Your basic problem is that DataContractJsonSerializer does not support untyped, free-form JSON data. As explained in Working with untyped JSON in a WCF service the System.Json namespace was added to Silverlight for this purpose, but it seems that it never made it into the full .Net class library.
Instead, in your stateless microservice can do a nested serialization where the free-form JSON is represented as an escaped string literal when serializing using the data contract serializer. Thus your classes would look something like this:
[DataContract]
[JsonObject]
public abstract class documentbase
{
[DataMember]
[JsonProperty]
public int id { get; set; }
[DataMember]
[JsonProperty]
public string type { get; set; }
[IgnoreDataMember]
[JsonProperty("content")]
public abstract JToken JsonContent { get; set; }
[JsonIgnore]
[DataMember(Name = "content")]
string DataContractContent
{
get
{
if (JsonContent == null)
return null;
return JsonContent.ToString(Newtonsoft.Json.Formatting.None);
}
set
{
if (string.IsNullOrEmpty(value))
JsonContent = null;
else
JsonContent = JToken.Parse(value);
}
}
}
[DataContract]
[JsonObject]
public class document : documentbase
{
JToken content;
public override JToken JsonContent { get { return content; } set { content = value; } }
}
[DataContract]
[JsonObject]
public class document<T> : documentbase where T : class
{
[IgnoreDataMember]
[JsonIgnore]
public T Content { get; set; }
public override JToken JsonContent
{
get
{
if (Content == null)
return null;
return JToken.FromObject(Content);
}
set
{
if (value == null || value.Type == JTokenType.Null)
Content = null;
else
Content = value.ToObject<T>();
}
}
}
Then the JSON generated by SerializeObject<document>(A) will look like:
{
"content":"{\"x\":1,\"y\":2}",
"id":1,
"type":"A"
}
Then, on the receiving system, you can deserialize to a document using the data contract serializer, then query the deserialized JToken JsonContent with LINQ to JSON. Alternatively, if the receiving system knows to expect a document<acontent> it can deserialize the data contract JSON as such, since document and document<T> have identical data contracts.

Have you looked into changing away from DataContractSerializer to a serializer with better support instead? Here's how you'd plug in a different serializer.
class InitializationCallbackAdapter
{
public Task OnInitialize()
{
this.StateManager.TryAddStateSerializer(new MyStateSerializer());
return Task.FromResult(true);
}
public IReliableStateManager StateManager { get; set; }
}
class MyStatefulService : StatefulService
{
public MyStatefulService(StatefulServiceContext context)
: this(context, new InitializationCallbackAdapter())
{
}
public MyStatefulService(StatefulServiceContext context, InitializationCallbackAdapter adapter)
: base(context, new ReliableStateManager(context, new ReliableStateManagerConfiguration(onInitializeStateSerializersEvent: adapter.OnInitialize)))
{
adapter.StateManager = this.StateManager;
}
}
This could be newtonsoft or whatever. Also I believe that the method is currently marked "Deprecated" however there's no alternative, so if it solves your problem go ahead and use it.

How to deserialize specific element with DataContractJsonSerializer

I'm trying to deserialize json data with DataContractJsonSerializer class. a problem is how to set root element?
my json data is here.
{
"delete":{
"status":{
"id":696142765093072896,
"id_str":"696142765093072896",
"user_id":2223183576,
"user_id_str":"2223183576"
},
"timestamp_ms":"1454808363540"
}
}
and I wrote class for deserialization like this. but it isn't works. my Status always null.
[DataContract(Name="delete")]
public class Delete
{
[DataMember(Name="status")]
public DeletedStatus Status { get; set; }
}
public class DeletedStatus
{
[DataMember(Name = "id")]
public long Id { get; set; }
[DataMember(Name = "user_id")]
public long UserId { get; set; }
}
how can I start parse json from specific element?

Based on what I can tell from the JSON, the deserialization appears to be failing because the root property of the object is the "delete" property. I don't believe this will work with the DataContractJsonSerializer simply because the given type will not match the Delete type. One other possible issue is that I see the DeleteStatus class is missing a [DataContract] attribute.
Long story short, there is no simple way of doing what you want to do. That being said, there is a short and sweet way of deserializing the JSON without adding a lot of extra headache. I suggest creating a data type that represents the JSON in its current state, and deserialize to that type instead.
I wrote a Unit Test that you can run from a Visual Studio test project. I hope this helps.
JsonDeserializationTests.cs
using Microsoft.VisualStudio.TestTools.UnitTesting;
using System.Runtime.Serialization.Json;
using System.IO;
namespace SerializationTests {
[TestClass]
public class JsonDeserializationTests {
[TestMethod]
public void Deserialize_Delete_Type_Success() {
string json = string.Empty;
//Set the DataContractJsonSerializer target type to our wrapper type.
var ser = new DataContractJsonSerializer(typeof(DeleteWrapperJsonResult));
//Create an instance of the wrapper that reflects the JSON that you gave.
//This will help me mock the data that you gave.
var deleteWrapper = new DeleteWrapperJsonResult {
delete = new DeleteJsonResult {
status = new DeletedStatusJsonResult {
id = 696142765093072896,
user_id = 2223183576
}
}
};
//Convert the mock data to JSON to reflect the JSON that you gave.
using (var serStream = new MemoryStream()) {
using (var sr = new StreamReader(serStream)) {
ser.WriteObject(serStream, deleteWrapper);
serStream.Position = 0;
json = sr.ReadToEnd(); //Set the JSON string here.
//Output "{\"delete\":{\"status\":{\"id\":696142765093072896,\"id_str\":\"696142765093072896\",\"user_id\":2223183576,\"user_id_str\":\"2223183576\"}}}"
}
}
//Prepeare to Deserialize the JSON.
var deserialized = default(DeleteWrapperJsonResult);
using (var deserStream = new MemoryStream()) {
using (var sw = new StreamWriter(deserStream)) {
sw.Write(json); //Write the JSON to the MemoryStream
sw.Flush();
deserStream.Seek(0, SeekOrigin.Begin);
//Deserialize the JSON into an instance of our wrapper class.
//This works because of the structure of the JSON.
deserialized = (DeleteWrapperJsonResult)ser.ReadObject(deserStream);
}
}
//Initialize the actual Delete instanace with what was deserialized.
var delete = new Delete {
Status = new DeletedStatus {
//These values were populated with the JSON values.
UserId = deserialized.delete.status.user_id,
Id = deserialized.delete.status.id
}
};
//Write asserts around what was given and check for equality.
Assert.AreEqual(delete.Status.UserId, deleteWrapper.delete.status.user_id);
Assert.AreEqual(delete.Status.Id, deleteWrapper.delete.status.id);
//Test Passes for Me
}
}
}
Delete.cs
using System.Runtime.Serialization;
namespace SerializationTests {
[DataContract]
[KnownType(typeof(Delete))]
public class Delete {
[DataMember]
public DeletedStatus Status { get; set; }
}
[DataContract]
[KnownType(typeof(DeletedStatus))]
public class DeletedStatus {
[DataMember]
public long Id { get; set; }
[DataMember]
public long UserId { get; set; }
}
/**************************************************************
These types below are what comprise our wrapper class so that we can
use the JSON in its current state. The wrapper classes have properties that
are synonymous with the JSON properties.
**************************************************************/
//This structure represents the object nesting as it appears currently in your example.
[DataContract]
[KnownType(typeof(DeleteJsonResult))]
public class DeleteWrapperJsonResult {
[DataMember]
public DeleteJsonResult delete { get; set; }
}
[DataContract]
[KnownType(typeof(DeleteJsonResult))]
public class DeleteJsonResult {
[DataMember]
public DeletedStatusJsonResult status { get; set; }
}
[DataContract]
[KnownType(typeof(DeletedStatusJsonResult))]
public class DeletedStatusJsonResult {
[DataMember]
public long id { get; set; }
[DataMember]
public string id_str {
get {
return id.ToString();
}
set {
return;
}
}
[DataMember]
public long user_id { get; set; }
[DataMember]
public string user_id_str {
get {
return user_id.ToString();
}
set {
return;
}
}
}
}
As of the time of this writing, my unit test is passing! Let me know if I can assist further.

Deserializing an XML array from a web api

First off, I followed the answer given here, but I still can not get the following to work.
I am retrieving XML from a web API, and the results returned are as such:
<ArrayOf__ptd_student_charges
xmlns="http://schemas.datacontract.org/2004/07/something.something"
xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
<__ptd_student_charges>
<accumulated_tuition>000.000</accumulated_tuition>
<course_id>AAA-000/L</course_id>
<invoice_date>01/01/2015</invoice_date>
<lecturer_name>John Doe</lecturer_name>
<net_tuition>000.000</net_tuition>
<section_no>1</section_no>
<semester>Summer</semester>
<student_id>123456</student_id>
<student_name>John Doe</student_name>
<year>2015</year>
</__ptd_student_charges>
<__ptd_student_charges>
<accumulated_tuition>000.000</accumulated_tuition>
<course_id>AAA-000/L</course_id>
<invoice_date>01/01/2015</invoice_date>
<lecturer_name>John Doe</lecturer_name>
<net_tuition>000.000</net_tuition>
<section_no>1</section_no>
<semester>Summer</semester>
<student_id>123456</student_id>
<student_name>John Doe</student_name>
<year>2015</year>
</__ptd_student_charges>
</ArrayOf__ptd_student_charges>
I'm trying to deserialize this into an array of students.
My student class is defined like this:
public class Student
{
[System.Xml.Serialization.XmlElement("accumulated_tuiton")]
public double AccumulatedTution { get; set; }
[System.Xml.Serialization.XmlElement("net_tuiton")]
public double NetTuiton { get; set; }
[System.Xml.Serialization.XmlElement("course_id")]
public string CourseID { get; set; }
[System.Xml.Serialization.XmlElement("invoice_date")]
public DateTime InvoiceDate { get; set; }
[System.Xml.Serialization.XmlElement("lecturer_name")]
public string LecturerName { get; set; }
[System.Xml.Serialization.XmlElement("semester")]
public string Semester { get; set; }
[System.Xml.Serialization.XmlElement("student_id")]
public string StudentId { get; set; }
[System.Xml.Serialization.XmlElement("student_name")]
public string StudentName { get; set; }
[System.Xml.Serialization.XmlElement("year")]
public string Year { get; set; }
[System.Xml.Serialization.XmlElement("section_no")]
public int Section { get; set; }
}
And my student collection is defined like this:
[System.Xml.Serialization.XmlRoot("ArrayOf__ptd_student_charges xmlns=\"http://schemas.datacontract.org/2004/07/something.something\" xmlns:i=\"http://www.w3.org/2001/XMLSchema-instance")]
public class StudentCollection
{
[XmlArray("ArrayOf__ptd_student_charges")]
[XmlArrayItem("__ptd_student_charges", typeof(Student))]
public Student[] StudentArray { get; set; }
}
I'm deserializing the results using this code:
private void MainWindow_Loaded(object sender, RoutedEventArgs e)
{
StudentCollection collection;
HttpWebRequest request = WebRequest.Create(stringUrl) as HttpWebRequest;
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
XmlTextReader reader = new XmlTextReader(response.GetResponseStream());
XmlSerializer serializer = new XmlSerializer(typeof(StudentCollection));
collection = (StudentCollection)serializer.Deserialize(reader);
reader.Close();
}
Once I run this, I get an InvalidOperationException with a message
ArrayOf__ptd_student_charges
xmlns='http://schemas.datacontract.org/2004/07/something.something'>
was not expected.
I know that the xmlns:... shouldn't be in the first tag, but unfortunately it is and I'm unsure on how to proceed.

Basically, you need to support the default XML namespace in your XML file - you can either do this by specifying it on the StudentCollection:
[System.Xml.Serialization.XmlRoot("ArrayOf__ptd_student_charges")]
[System.Xml.Serialization.XmlRootAttribute(Namespace = "http://schemas.datacontract.org/2004/07/something.something", IsNullable = false)]
public class StudentCollection
{
[XmlArray("ArrayOf__ptd_student_charges")]
[XmlArrayItem("__ptd_student_charges", typeof(Student))]
public Student[] StudentArray { get; set; }
}
and the actual Student class:
[System.Xml.Serialization.XmlRootAttribute(Namespace = "http://schemas.datacontract.org/2004/07/something.something", IsNullable = false)]
public class Student
{
..........
}
or you can specify it programmatically when you deserialize:
XmlSerializer serializer = new XmlSerializer(typeof(StudentCollection),
"http://schemas.datacontract.org/2004/07/something.something");
That second parameter for the XmlSerializer is the default XML namespace to use when deserializing the XML content.
Extra tipp: if you ever have an XML file again, and you need to get the C# code classes that represent that XML - if you have Visual Studio 2012 or newer, just create a new code class, copy your XML file into the clipboard, and then use Edit > Paste Special > Paste XML as classes and you get all your C# including all XML attribute and XML namespaces and everything pasted into your Visual Studio right there

Alter XML root name [duplicate]

First off, I followed the answer given here, but I still can not get the following to work.
I am retrieving XML from a web API, and the results returned are as such:
<ArrayOf__ptd_student_charges
xmlns="http://schemas.datacontract.org/2004/07/something.something"
xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
<__ptd_student_charges>
<accumulated_tuition>000.000</accumulated_tuition>
<course_id>AAA-000/L</course_id>
<invoice_date>01/01/2015</invoice_date>
<lecturer_name>John Doe</lecturer_name>
<net_tuition>000.000</net_tuition>
<section_no>1</section_no>
<semester>Summer</semester>
<student_id>123456</student_id>
<student_name>John Doe</student_name>
<year>2015</year>
</__ptd_student_charges>
<__ptd_student_charges>
<accumulated_tuition>000.000</accumulated_tuition>
<course_id>AAA-000/L</course_id>
<invoice_date>01/01/2015</invoice_date>
<lecturer_name>John Doe</lecturer_name>
<net_tuition>000.000</net_tuition>
<section_no>1</section_no>
<semester>Summer</semester>
<student_id>123456</student_id>
<student_name>John Doe</student_name>
<year>2015</year>
</__ptd_student_charges>
</ArrayOf__ptd_student_charges>
I'm trying to deserialize this into an array of students.
My student class is defined like this:
public class Student
{
[System.Xml.Serialization.XmlElement("accumulated_tuiton")]
public double AccumulatedTution { get; set; }
[System.Xml.Serialization.XmlElement("net_tuiton")]
public double NetTuiton { get; set; }
[System.Xml.Serialization.XmlElement("course_id")]
public string CourseID { get; set; }
[System.Xml.Serialization.XmlElement("invoice_date")]
public DateTime InvoiceDate { get; set; }
[System.Xml.Serialization.XmlElement("lecturer_name")]
public string LecturerName { get; set; }
[System.Xml.Serialization.XmlElement("semester")]
public string Semester { get; set; }
[System.Xml.Serialization.XmlElement("student_id")]
public string StudentId { get; set; }
[System.Xml.Serialization.XmlElement("student_name")]
public string StudentName { get; set; }
[System.Xml.Serialization.XmlElement("year")]
public string Year { get; set; }
[System.Xml.Serialization.XmlElement("section_no")]
public int Section { get; set; }
}
And my student collection is defined like this:
[System.Xml.Serialization.XmlRoot("ArrayOf__ptd_student_charges xmlns=\"http://schemas.datacontract.org/2004/07/something.something\" xmlns:i=\"http://www.w3.org/2001/XMLSchema-instance")]
public class StudentCollection
{
[XmlArray("ArrayOf__ptd_student_charges")]
[XmlArrayItem("__ptd_student_charges", typeof(Student))]
public Student[] StudentArray { get; set; }
}
I'm deserializing the results using this code:
private void MainWindow_Loaded(object sender, RoutedEventArgs e)
{
StudentCollection collection;
HttpWebRequest request = WebRequest.Create(stringUrl) as HttpWebRequest;
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
XmlTextReader reader = new XmlTextReader(response.GetResponseStream());
XmlSerializer serializer = new XmlSerializer(typeof(StudentCollection));
collection = (StudentCollection)serializer.Deserialize(reader);
reader.Close();
}
Once I run this, I get an InvalidOperationException with a message
ArrayOf__ptd_student_charges
xmlns='http://schemas.datacontract.org/2004/07/something.something'>
was not expected.
I know that the xmlns:... shouldn't be in the first tag, but unfortunately it is and I'm unsure on how to proceed.

Basically, you need to support the default XML namespace in your XML file - you can either do this by specifying it on the StudentCollection:
[System.Xml.Serialization.XmlRoot("ArrayOf__ptd_student_charges")]
[System.Xml.Serialization.XmlRootAttribute(Namespace = "http://schemas.datacontract.org/2004/07/something.something", IsNullable = false)]
public class StudentCollection
{
[XmlArray("ArrayOf__ptd_student_charges")]
[XmlArrayItem("__ptd_student_charges", typeof(Student))]
public Student[] StudentArray { get; set; }
}
and the actual Student class:
[System.Xml.Serialization.XmlRootAttribute(Namespace = "http://schemas.datacontract.org/2004/07/something.something", IsNullable = false)]
public class Student
{
..........
}
or you can specify it programmatically when you deserialize:
XmlSerializer serializer = new XmlSerializer(typeof(StudentCollection),
"http://schemas.datacontract.org/2004/07/something.something");
That second parameter for the XmlSerializer is the default XML namespace to use when deserializing the XML content.
Extra tipp: if you ever have an XML file again, and you need to get the C# code classes that represent that XML - if you have Visual Studio 2012 or newer, just create a new code class, copy your XML file into the clipboard, and then use Edit > Paste Special > Paste XML as classes and you get all your C# including all XML attribute and XML namespaces and everything pasted into your Visual Studio right there