activerecord拾贝

>> Operator.first.tenants.send :has_cached_counter?

=> false

>> Operator.first.tenants.send :construct_sql

=> "`tenants`.operator_id = 0"

 

>> Operator.first.tenants.send :construct_scope

=> {:create=>{"operator_id"=>0}, :find=>{:readonly=>false, :include=>nil, :conditions=>"`tenants`.operator_id = 0", :limit=>10, :order=>nil}}

 

>> Operator.read_inheritable_attribute(:after_add_for_tenants)

=> [:do_after_add]

 

 

       # Validate all keys in a hash match *valid keys, raising ArgumentError on a mismatch.

        # Note that keys are NOT treated indifferently, meaning if you use strings for keys but assert symbols

        # as keys, this will fail.

        #

        # ==== Examples

        #   { :name => "Rob", :years => "28" }.assert_valid_keys(:name, :age) # => raises "ArgumentError: Unknown key(s): years"

        #   { :name => "Rob", :age => "28" }.assert_valid_keys("name", "age") # => raises "ArgumentError: Unknown key(s): name, age"

        #   { :name => "Rob", :age => "28" }.assert_valid_keys(:name, :age) # => passes, raises nothing

        def assert_valid_keys(*valid_keys)

          unknown_keys = keys - [valid_keys].flatten

          raise(ArgumentError, "Unknown key(s): #{unknown_keys.join(", ")}") unless unknown_keys.empty?

        end 

 

>> pp Operator.reflections.first

[:bills,

 #<ActiveRecord::Reflection::AssociationReflection:0x9927490

  @active_record=

   Operator(id: integer, host: string, title: string, logo_url: string, biglogo_url: string, footer: text, descr: text, telphone: string, contact: string, email: string, remember_token: string, crypted_password: string, salt: string, activated_at: date, activation_code: string, company: string, is_support_bank: boolean, bank: string, bank_account_name: string, bank_account: string, bank_tax_number: string, bank_payment_number: string, is_support_alipay: boolean, alipay_email: string, alipay_partner: string, alipay_key: string, created_at: datetime, updated_at: datetime, remember_token_expires_at: datetime, page_contact: text, page_about: text, amount: decimal),

  @macro=:has_many,

  @name=:bills,

  @options={:extend=>[]}>]

 

定义dependent 回调

>> pp Operator.new.methods.grep /has_many/

["has_many_dependent_destroy_for_tenants"]

 

>> Operator.methods.grep /after_add/

=> ["after_add_for_tenants"]

>> Operator.after_add_for_tenants

=> [:aaa]

 

 

 调用after_add

      def callback(method, record)

          callbacks_for(method).each do |callback|

            ActiveSupport::Callbacks::Callback.new(method, callback, record).call(@owner, record)

          end

        end

        def callbacks_for(callback_name)

          full_callback_name = "#{callback_name}_for_#{@reflection.name}"

          @owner.class.read_inheritable_attribute(full_callback_name.to_sym) || []

        end   

  base.define_callbacks *CALLBACKS