Support serialization of Newtonsoft JSON.NET JObject

[eduardocampano]

As the Newtonsoft JSON.NET JObject implements IEnumerable it is treated as an array for serialization instead of being serialized directly.

My issue came up in the following case: ASP.NET WebApi used JSON.NET to deserialize a complex JSON object during an API request. The deserialized type contains an IDictionary<string, object> property to allow custom info to be sent to the API. As part of the WebApi deserialization all the entries in the dictionary had JObject instance values. Trying to serialize the type instance again using SimpleJson the dictionary is not correctly serialized.

Thanks, Eduardo

[prabirshrestha]

can u post a sample code of class and json you are trying to serialize/deserialize.

[eduardocampano]

I just pushed 2 failing unit tests to my fork https://github.com/eduardocampano/simple-json/blob/f7f9238820b21663b7e38acb8fb66eb7b57c0e72/src/SimpleJson.Tests/SerializeObject.JsonNet.Tests.cs I tried using TrySerializeNonPrimitiveObject in the IJsonSerializerStrategy but the code tries to serialize them as arrays because they implement IEnumerable.

[prabirshrestha]

Why would you want to use both at the same time in the same code? The only place where you would want to use both at the same place would be server side using webapi and in client use simplejson.

[eduardocampano]

In this case I'm building a logging library which serializes objects using SimpleJson. A consumer of this library is using WebApi with the default Json.Net serializer and sending the objects to log to my library. For now I provided him a SimpleJsonFormatter for WebApi and it solved the particular issue. But I would not like to force the library consumers to make this kind of changes. Maybe the solution is to have a hook where I can define a TypeConverter like Json.Net to force a type to use a specific converter before evaluating the default ones, as JObject is not able to reach the TrySerializeNonPrimitiveObject method.

[prabirshrestha]

You might be interested in this discussion. https://twitter.com/PrabirShrestha/status/271392381226590209

Since JObject is IDictionary<string, JToken> we might need to check if it contains IDictionary<string, TAnything> then treat it as a json object. Or just try to cast it as IDictionary. Not sure if this works in all version of PCL.

[eduardocampano]

Right, that could help, I will give that a try, thanks

[eduardocampano]

Ok, I'm back on this after a while, casting as IDictionary doesn't work because IDictionary<,> does not implement it. I came up with this function

public bool IsIEnumerableKeyValuePairOfStringAndAnything(Type type)
{
    foreach (var interfaceType in type.GetInterfaces())
    {
        if (interfaceType.IsGenericType && interfaceType.GetGenericTypeDefinition() == typeof(IEnumerable<>))
        {
            var genericArgument = interfaceType.GetGenericArguments()[0]; 
            if (genericArgument.IsGenericType && genericArgument.GetGenericTypeDefinition() == typeof(KeyValuePair<,>)
                && genericArgument.GetGenericArguments()[0] == typeof(string))
            return true;
        }
    }

    return false;
}

It will check if the type to be serialized is an IEnumerable<KeyValuePair<string, TAnything>> so it can be treated as json object as you suggest. The current checks for IDictionary<string, object> and IDictionary<string, string> won't be necessary anymore. I haven't check its performance yet considering it will be executed a lot, results must be cached.

What do you think?