Saule

Adding metadata

Saule allows you to add metadata to responses that are returned from your API. To enable this for a resource, you need to override the GetMetadata method on your ApiResource:

public class PersonResource : ApiResource
{
    public override object GetMetadata(object response, Type resourceType, bool isEnumerable)
    {
        if (resourceType != typeof(Person))
        {
            return null;
        }

        if (isEnumerable)
        {
            var people = (IEnumerable<Person>) response;

            return new CollectionMetadata
            {
                Total = people.Count()
            }
        }
        else
        {
            var person = (Person)response;

            return new PersonMetadata
            {
                NumberOfFriends = friends.Count(),
                NumberOfFamilyMembers = family.Count()
            };

        }
    }
}

GetMetadata takes three parameters:

• response: The response object you returned from your action method (after filtering and pagination have been applied).
• resourceType: The type of the response you returned from your action method. If you returned a collection, this is the type of the items in the collection.
• isEnumerable: true if you returned an enumerable (type that derives from IEnumerable) from your action method, otherwise false.

Any object you return from this method will be serialized and included in the root object of the JSON API response under the meta property. If you want to serialize the object in a different way (e.g. camelCased properties), you can return a JToken from this method. The JToken will not be changed, but directly included in the response.