Rails范围 - 未定义的方法

Question

I have a model called "event" that has a scope named "upcoming" wich returns events that are dated in the future. In the rails console, whenever I type

Event.upcoming

It returns the subset of events successfully. However if I type:

@events = Event.all
@events.upcoming

I get an undefined method 'upcoming' error. Are scopes only working on the class and not on instantiated variables? Thanks in advance. Yohann

Answer 1

Once you call .all , @events is no longer an ActiveRelation , hence you cannot call a scope on it.

So, Event.where(SOME CONDITIONS).order(ORDERING).upcoming.limit(X) would still work, but Event.where(SOME CONDITIONS).order(ORDERING).all.upcoming.limit(X) would not work.

Answer 2

You can use scoped instead of all to get an active relation object that will allow you to chain scopes on the variable after it's been set:

@events = Event.scoped
@events.upcoming