How do I serialize an entire ActiveRecord Tree in Rails?

Question

class Node < ActiveRecord::Base
  attr_accessible :name

  belongs_to :parent_node, :class_name => "Node", :foreign_key => :parent_id
  has_many :child_nodes, :class_name => "Node", :foreign_key => :parent_id
end

For the root node, parent_id will be nill. Say I have the id of the root node, and wish to print the entire tree to the output stream in json format.

How do I go about doing that?

Assume the tree does not contain any loops.

Check this question http://stackoverflow.com/questions/9944005/how-to-generate-json-tree-from-ancestry — dimuch, Jun 09 '12 at 06:55

score 1 · Accepted Answer · answered Jun 24 '12 at 23:40

1

Sounds like you need awesome_nested_set. The wiki is well documented but can be hard to find if you don't know it's there.

In your case, you'll want to do something like:

Node.root.self_and_descendants

answered Jun 24 '12 at 23:40

Zubin

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I was hoping what I wanted was in rails base, but this looks like it solves the problem, thanks :) – The Trav Jun 25 '12 at 23:21

How do I serialize an entire ActiveRecord Tree in Rails?

1 Answers1