output deeply nested json associations

Question

I've got a rails3 app with the following structure

Users
  has_many :tasks
  has_many :staff
  has_many :managers

Tasks 
  has_one :location

Locations
  has_many :staff
  has_one :manager

Staff
  belongs_to :users
  belongs_to :location

Managers
  belongs_to :users
  belongs_to :location

Now in my json output, I'm trying to get a the User, their tasks, each task location, and the locations staff and manager.

I've got

 @User = User.find(params[:id], :include{:tasks=>:location})

This outputs the user and locations of the tasks, but not the tasks themselves.

And any further includes I attempt to add, result in an error for example

@User =  User.find(params[:id], :include{:tasks=>:location=>:staff})

I get an error of "unexpected tASSOC, expecting }.

What is the correct way to write this so I get all the associated data for this user?

Pan Thomakos Pan Thomakos · Accepted Answer · 2011-02-25T20:07:48

You should be able to get the user and associated objects using this command:

@user = User.includes(:tasks => {:location => :staff}).find(params[:id])

You'll see a few queries execute. The first will retrieve the user, the second the related tasks, the third the related locations and the fourth the related staff. You'll notice that no queries execute when you type any of the following:

@user.tasks.first.location.staff
@user.tasks.first.location
@user.tasks.first

output deeply nested json associations

1 Answers