JSON.NET–Resolve private setters

On one of my projects we are using event sourcing as our data persistence strategy. Based on the event stream I build projections using read models.

I prefer to keep my projected read model immutable but turns out that JSON.NET fails to deserialize the state. All properties retain their default values.

	public class Product
	{
	public Guid Id { get; private set; }
	public string Name { get; private set; }
	}

view raw MyReadModel.cs hosted with ❤ by GitHub

A solution is to create a custom contract resolver that uses reflection to set the property values:

	internal class ResolvePrivateSetters : DefaultContractResolver
	{
	protected override JsonProperty CreateProperty(
	MemberInfo member,
	MemberSerialization memberSerialization)
	{
	var prop = base.CreateProperty(member, memberSerialization);
	if (!prop.Writable)
	{
	var property = member as PropertyInfo;
	if (property != null)
	{
	var hasPrivateSetter = property.GetSetMethod(true) != null;
	prop.Writable = hasPrivateSetter;
	}
	}
	return prop;
	}
	}

view raw ResolvePrivateSetters.cs hosted with ❤ by GitHub

Don't forget to apply this contract resolver using the JsonSerializerSettings:

	var settings = new JsonSerializerSettings()
	{
	ContractResolver= new ResolvePrivateSetters()
	};
	JsonConvert.DeserializeObject(json, settings);

view raw Deserialize.cs hosted with ❤ by GitHub