public Task <StarWarsCharacter[]> Friends(Droid source)
{
var friends = source.Friends ?? new string[0];
// Get or add a batch loader with the key "GetCharacterById"
// The loader will call FetchCharacterByIdAsync for each batch of keys
var loader = _accessor.Context.GetOrAddBatchLoader <string, StarWarsCharacter>("GetCharacterById", _service.FetchCharacterByIdAsync);
// Add the list of friend ids to the pending keys to fetch
// The task will complete once all of the FetchCharacterByIdAsync() returns with the batched results
return(loader.LoadAsync(friends));
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
var obj = JObject.Load(reader);
StarWarsCharacter character;
if (obj.ContainsKey("homePlanet"))
{
character = new Human();
}
else
{
character = new Droid();
}
serializer.Populate(obj.CreateReader(), character);
return(character);
}
public string Description(Droid source)
{
return($"{source.Name} is a {source.Function} droid.");
}
public string PrimaryFunction(Droid source) => source.Function;
public Task <StarWarsCharacter[]> Friends(Droid source)
{
var friends = source.Friends ?? new string[0];
return(Task.WhenAll(friends.Select(id => _service.FetchCharacterByIdAsync <StarWarsCharacter>(id))));
}
