无法嵌套 JSON Rails

Question

我无法通过 rails 嵌套具有 has_many through 关系的对象。

我的模型如下所示：

class SessionDetail < ActiveRecord::Base
 has_many :session_enrollments, dependent: :destroy
 has_many :customers, through: :session_enrollments
end

class SessionEnrollment < ActiveRecord::Base
 belongs_to :customers   //column name is "customers_id"
 belongs_to :session_details //column name is "sessiondetails_id"
end

class Customer < ActiveRecord::Base
 has_many :session_enrollments
 has_many :session_details, through: :session_enrollments
end

---

我正在尝试嵌套一个 json 对象以返回一组会话详细信息，其中包含一个客户子数组和一个 session_enrollments 子数组（一个对象）

我的控制器当前看起来像这样：

def return_trainers_sessions
  @trainer_requests = SessionDetail.where(trainers_id: params[:trainers_id], state:     "PENDING")

  unless (!@trainer_requests.any?)
    respond_to do |format|
    msg = {:status => "SUCCESS", :messages => "Requests Found", :requests => @trainer_requests.as_json(:includes => {:customers => {:include =>:session_enrollments}})}
     format.json  { render :json => msg } # don't do msg.to_json
  end

我也尝试过创建一个类方法，但只能嵌套客户。

我最终没有返回任何客户或 session_enrollments，所以我的 json 看起来就像我从未将包含添加到 .as_json 的右侧

Answer 1

注意你的复数形式。

class SessionDetail < ActiveRecord::Base
  has_many :session_enrollments, dependent: :destroy
  has_many :customers, through: :session_enrollments
end

# a session enrollment belongs to a single customer, and a single session detail. Similarly
# the foreign key fields should be singular, customer_id, session_detail_id
class SessionEnrollment < ActiveRecord::Base
  belongs_to :customer   
  belongs_to :session_detail
end

class Customer < ActiveRecord::Base
  has_many :session_enrollments
  has_many :session_details, through: :session_enrollments
end