Projected fields

Fields with an id are not projected by default, by you can ask the API to do so by passing a projectionFields parameter.

Here's a sample Campaign with no projected fields :

{
  _id: "123456789abcfef1234567890",
  name: "My campaign",
  userId: "abc123456789fef1234567890",
  etc...
}

And with the populated user :

{
  _id: "123456789abcfef1234567890",
  name: "My campaign",
  userId: {
    _id: "abc123456789fef1234567890",
    first_name: "Romain",
    last_name: "Simon"
  },
  etc...
}

Here are infos available in populated fields for different resources :

campaigns:
    userId: {
        _id,
        first_name,
        last_name
    }
}

contacts:
    userId: {
        first_name,
        last_name
    },
    listId: {
        list_name,
    }
}

lists:
    userId: {
        _id,
        first_name,
        last_name
    }
}

messages:
    campaignId: {
        _id,
        name
    },
    contactFields: {
        _id,
        first_name,
        last_name,
        email
    }
}

templates:
    userId: {
        first_name,
        last_name
    }
}

variables:
    userId: {
        first_name,
        last_name
    }
}