我想决定在我的控制器中输出的属性数量.
但我不知道必须这样做吗？
controller.rb
respond_to do |format|
if fields
# less attributes : only a,c
elsif xxx
# default attributes
else
# all attributes : a,c,b,d,...
end
end
serializer.rb
class WeatherLogSerializer < ActiveModel::Serializer
attributes :id,:temperature
def temperature
"Celsius: #{object.air_temperature.to_f}"
end
end
解决方法
我可能会为所有人使用不同的端点,但您也可以传入不同的url参数或类似的东西.通常情况下,我认为您希望默认值更加有限.
以下是我建议的方法：
调节器
所有人的不同终点
render json: objects,each_serializer: WeatherLogAllSerializer
允许自定义字段
fields = params[:fields] # Csv string of specified fields. # pass the fields into the scope if fields.present? render json: objects,each_serializer: WeatherLogCustomSerializer,scope: fields else render json: objects,each_serializer: WeatherLogSerializer end
三种不同的序列化器：全部,默认,自定义
所有
class WeatherLogAllSerializer < ActiveModel::Serializer
attributes :id,:temperature,:precipitation,:precipitation
has_many :measurements
def temperature
"Celsius: #{object.air_temperature.to_f}"
end
end
默认
class WeatherLogSerializer < ActiveModel::Serializer
attributes :id,:temperature
def temperature
"Celsius: #{object.air_temperature.to_f}"
end
end
习惯
class WeatherLogCustomSerializer < WeatherLogSerializer
def attributes
data = super
if scope
scope.split(",").each do |field|
if field == 'precipitation'
data[:precipitation] = object.precipitation
elsif field == 'humidity'
data[:humidity] = object.humidity
elsif field == 'measurements'
data[:measurements] = ActiveModel::ArraySerializer.new(object.measurements)
end
end
end
data
end
end