I was updating an example build using the better_nested_set to use the awesome_nested_set. One thing that I didn’t find in awesome_nested_set are some helper methods that are returning a full tree of the nested set as one XML document. With better nested set I could do
Category.result_to_attributes_xml(Category.root.ancestors)
So I have added the following full_xml method to my nested active record to recurse all the children. Note that the full_method calls the full_method on the children passing along the xml builder that is created by the to_xml method and passed as the xml variable to block, thus building a nested XML document.
class Category < ActiveRecord::Base
belongs_to :parent, :class_name => “Category”
acts_as_nested_set
def full_xml(builder=nil)
to_xml(:builder => builder, :skip_instruct => true) do |xml|
children.each { |child| child.full_xml(xml) }
end
end
end
Obviously it would be nice that the awesome_nested_set provides such a method.
So let’s assume I create the following nested structure:
Category.transaction do
root = Category.create(:name => “Main Category”)
cameras = Category.create(:name => “Cameras & Photo”)
cameras.move_to_child_of(root)
Category.create(:name => “Bags”, :qty_in_stock => 2).move_to_child_of(cameras)
Category.create(:name => “Accessories”, :qty_in_stock => 12).move_to_child_of(cameras)
Category.create(:name => “Analog Cameras”, :qty_in_stock => 0).move_to_child_of(cameras)
Category.create(:name => “Digital Cameras”, :qty_in_stock => 5).move_to_child_of(cameras)
phones = Category.create(:name => “Cell Phones”)
phones.move_to_child_of(root)
Category.create(:name => “Accessories”, :qty_in_stock => 8).move_to_child_of(phones)
Category.create(:name => “Phones”, :qty_in_stock => 20).move_to_child_of(phones)
Category.create(:name => “Prepaid Cards”, :qty_in_stock => 3).move_to_child_of(phones)
dvds = Category.create(:name => “Dvds”)
dvds.move_to_child_of(root)
Category.create(:name => “Blueray”, :qty_in_stock => 10).move_to_child_of(dvds)
Category.create(:name => “HD DVD”, :qty_in_stock => 0).move_to_child_of(dvds)
Category.create(:name => “DVD”, :qty_in_stock => 100).move_to_child_of(dvds)
end
I can now get the whole nested structure in one go:
Category.roots.first.full_xml
And get the following XML in return.
<typo:code lang=“xml>
”datetime">2008-08-18T14:46:07Z
1
1
Main Category
28
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
11
2
Dvds
1
9
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
14
3
DVD
11
100
4
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
13
5
HD DVD
11
0
6
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
12
7
Blueray
11
10
8
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
7
10
Cell Phones
1
17
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
10
11
Prepaid Cards
7
3
12
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
9
13
Phones
7
20
14
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
8
15
Accessories
7
8
16
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
2
18
Cameras & Photo
1
27
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
6
19
Digital Cameras
2
5
20
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
5
21
Analog Cameras
2
0
22
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
4
23
Accessories
2
12
24
2008-08-18T14:46:07Z
2008-08-18T14:46:07Z
3
25
Bags
2
2
26
2008-08-18T14:46:07Z
How do you deal with that situation?
