Serialized headaches when you combine .NET Core and .NET 4.6

When I'm involved in an application development project, I try all the time to keep the language ecosystem reduced as much as possible. Even if we are leaving in a world where interoperability is higher than ever, there are times when because of this you can lose a lot of time because of it.

Let's take the below example:

• An Azure Function application wrote in .NET 4.6 that send messages to Azure Service Bus Topic. Inside the message body content is serialized in JSON format
• An Azure Web App application wrote in .NET Core that receives messages from Azure Service Topic and displays it on the UI.

Everything it is okay until you run the code and an error occurs during deserialization. When you take a look at what you send and receive you see the following:

.NET 4.6 OUTPUT:       @ string 3http://schemas.microsoft.com/2003/10/Serialization/�k{"CountryCode":"RO","AlertType":0,"Level":5,"ValidFrom":"2018-04-05T10:14:00.0458475Z","Period":"00:02:00"}

.NET Core EXPECT:    {"CountryCode":"RO","AlertType":0,"Level":5,"ValidFrom":"2018-04-05T10:14:00.0458475Z","Period":"00:02:00"}

Both implementations are using Newtonsoft library for content serialization and deserialization, but it seems that the behavior is different.

.NET 4.6 Sample

string jsonWeatherAlert = JsonConvert.SerializeObject(weatherAlert);
BrokeredMessage message = new BrokeredMessage(jsonWeatherAlert);
message.Properties.Add("countrycode", weatherAlert.CountryCode);
topicClient.Send(message);

.NET Core Sample

string bytesAsString = Encoding.UTF8.GetString(message.Body);
WeatherAlert alert = JsonConvert.DeserializeObject<WeatherAlert>(bytesAsString);

The root cause of this problem is related to what kind of default serializer it is used behind the scene. One of them it is using DataContract and bytes directly from the stream VS the other one that it is using DataContractBinarySerializer and GetBody<Streeam> to load all bytes.
This difference has a direct impact not only on the Newtonsoft library but also to Service Bus library if you want to use it directly.

To solve the problem you need on the sender or received to change the default serializer library that it is used. In our case, we updated the .NET 4.6 implementation in the following way.

var jsonSerializar = new DataContractJsonSerializer(typeof(WeatherAlert)); 
BrokeredMessage message = new BrokeredMessage(weatherAlert, jsonSerializar); 
message.Properties.Add("countrycode", weatherAlert.CountryCode); topicClient.Send(message);

If you want to find more about it, I invite you to read the following link discussion https://github.com/Azure/azure-service-bus-dotnet/issues/239