Contents

#coding: utf-8
=begin
  字段映射，业务字段-数据库字段对应
=end
module FieldMapping
  def self.included(base)
    #TODO 条件检查
    base.extend(ClassMethods)
  end

  def as_json(options={})
    self.class.buz_hashize(self.attributes)
  end

  def update_from_buz(params={})
    update_attributes(self.class.db_hashize(params))
  end
  
  module ClassMethods
    def new_from_buz(params={})
      new(db_hashize(params))
    end
    
    def create_from_buz(params={})
      create(db_hashize(params))
    end
    
    #TODO 在包装类提供此方法，可在include前检查
    def field_maps
      raise "Not implemented!"
    end

    def inspect_fields
      puts "#buz fields\t\t#db fields\t\t #the rules"
      field_maps.each do |k, v|
        puts "#{k}\t\t #{v}           "
      end
    end

    def get_map_value(k, value)
      #raise "Not implemented!"
      value
    end
   
    #业务层到数据层字段的转换
    def db_hashize(params={})
      new_params = params.symbolize_keys
      common_keys = new_params.keys & field_maps.keys
      common_keys.inject({}) do |r, e|
        r[field_maps[e]] = get_map_value(e, new_params[e])
        r
      end
    end
 
    #转成业务层key表示
    def buz_hashize(attrs={})
      #return {} if attrs.blank?
      #获取默认初始值
      attrs = new.attributes if attrs.blank?
      new_attrs = attrs.symbolize_keys
      invert_maps = field_maps.invert
      common_db_attrs = new_attrs.keys & invert_maps.keys
      common_db_attrs.inject({}) do |r, da| 
        ba = invert_maps[da]
        r[ba]=get_map_value(ba, new_attrs[da])
        r
      end
    end
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
ns_service_pack-0.0.2	lib/ns_service_pack/field_mapping.rb
ns_service_pack-0.0.1	lib/ns_service_pack/field_mapping.rb