How do I add an `.order` invocation to a ActiveRecord collection that I retrieved?

Question

I am new in this world of Rails. And I cannot get my head around this problem. How to get @microposts ordered by the date the micropost was created.

This is the line

 @microposts = current_user.followeds.map(&:microposts).flatten

I only managed to order by date the 'followeds', but that is not what I am looking for. All the attempts I have made gave me errors, so I guess I am not aware of some syntax.

Any help is welcome!

Answer 1

Normally, you would add an order clause, as in:

Micropost.where(:written_by => current_user.followeds).order(:created_at)

The way you currently have this line structured doesn't permit that, however, since order is only available on ActiveRecord::Relations, and once you do map you no longer have a Relation available to chain on.

If that's the case, you'll want something like:

current_user.followeds.map(&:microposts).flatten.sort_by { |m| m.created_at }

Answer 2

I think you should try to approach this from another angle.

How about something like this:

@microposts = Micropost.where(author_id: current_user.followed_ids).order(:created_at).all

You might of course have to exchange author_id for whatever foreign key you have to identify what user a Micropost was written by.

If you want to reverse the posts (newest first), you just write order("created_at desc") instead.