lib/parse/model/classes/user.rb
def link_auth_data!(service_name, **data)
      response = client.set_service_auth_data(id, service_name, data)
      raise Parse::Client::ResponseError, response if response.error?
      apply_attributes!(response.result)
    end
def link_auth_data!(service_name, **data)
      response = client.set_service_auth_data(id, service_name, data)
      raise Parse::Client::ResponseError, response if response.error?
      apply_attributes!(response.result)
    end
Adds the third-party authentication data to for a given service.
 @param service_name [Symbol] The name of the service (ex. :facebook)
 @param data [Hash] The body of the OAuth data. Dependent on each service.
 @raise [Parse::Client::ResponseError] If user was not successfully linked