How about you create a module like:
module Ancestry
def self.extended(receiver)
receiver.class_eval do
define_method(:children_ids) do |children_ary=[]|
receiver[:child].each_with_object(children_ary) do |child, children_ary|
children_ary << child[:id]
child.extend(Ancestry).children_ids(children_ary)
end if receiver[:child].any?
end
define_method(:parent_ids) do |parents_ary=[]|
if receiver[:child].any?
parents_ary << receiver[:id]
receiver[:child].each_with_object(parents_ary) do |child, parents_ary|
child.extend(Ancestry).parent_ids(parents_ary)
end
end
end
define_method(:node) do |node_id|
return receiver if receiver[:id] == node_id
receiver[:child].each do |child|
child.extend(Ancestry).node(node_id).tap do |x|
return x unless x.blank?
end
end if receiver[:child]
{}.extend(Ancestry)
end
define_method(:child) do
receiver[:child] || []
end
end
end
end
Then extend your hash
like this:
data = {
"id": 1,
"child": [
{
"id": 1847,
"child": [
{
"id": 8078,
"child": []
},
{
"id": 3380,
"child": [
{
"id": 561,
"child": []
},
{
"id": 706,
"child": []
}
]
}
]
}
]
}.with_indifferent_access.extend(Ancestry)
Now you can do:
data.children_ids
=> [1847, 8078, 3380, 561, 706]
data.parent_ids
=> [1, 1847, 3380]
data.node(1847).node(3380).child
=> [{"id"=>561, "child"=>[]}, {"id"=>706, "child"=>[]}]
data.node(9999).node(3380).child
=> []
data.node(1847).node(9999).child
=> []
data.node(1847).node(3380).node(561).child
=> []