Ruby on rails 如何防止RoR中的并行访问?
有一个控制器Ruby on rails 如何防止RoR中的并行访问?,ruby-on-rails,ruby,Ruby On Rails,Ruby,有一个控制器 can_buy = nil if game.spot_price == 0 return {json: {error: 1, error_message: "You can do it only once"}, status: 400} if game.spots.where(user_id: user.id).length > 0 can_buy = true else can_buy = UserService.have_enough_money?(user,
can_buy = nil
if game.spot_price == 0
return {json: {error: 1, error_message: "You can do it only once"}, status: 400} if game.spots.where(user_id: user.id).length > 0
can_buy = true
else
can_buy = UserService.have_enough_money?(user, game.spot_price)
end
if can_buy
ActiveRecord::Base.transaction do
# purchase goes here
end
end
如果用户在同一时刻提出几个请求,而现货价格为0,他可以购买几次,但只能购买一次。
如何预防?
注意:对不起,我的英语很差
请早点开始交易:
if game.spot_price.zero? && game.spots.where(user_id: user.id).length > 0
return json: {error: 1, error_message: "You can do it only once"},
status: 400
end
ActiveRecord::Base.transaction do
if game.spot_price.zero? || UserService.have_enough_money?(user, game.spot_price)
...
else
raise ActiveRecord::Rollback, "Not permitted!"
end
end
旁注:can\u buy=nil
是多余的<代码>如果运算符未定义嵌套范围。