Iteration through array data - ruby

Question

I have a JSON data which in the following format:
[{
"id": 1,
"children": [{
"id": 7,
"children": [{
"id": 8,
"children": [{
"id": 4
}, {
"id": 5
}, {
"id": 11
}
]
}, {
"id": 9
}
]
}, {
"id": 6
}, {
"id": 10
}
]
}, {
"id": 2,
"children": [{
"id": 3
}, {
"id": 12
}
]
}, {
"id": 13
}
]
The tree for this JSON data is:
I want to loop through all the nodes and extract the "id" of all data maintaining its parent child hierarchy. How can i do this using recursive function.
The idea is to parse the json structure in ruby.

Answer 1

I just coded a node js code, you can still make it work on a browser in js, but you will need to download the underscore library here.
_und = require('underscore');
data = [{
"id": 1,
"children": [{
"id": 7,
"children": [{
"id": 8,
"children": [{
"id": 4
}, {
"id": 5
}, {
"id": 11
}
]
}, {
"id": 9
}
]
}, {
"id": 6
}, {
"id": 10
}
]
}, {
"id": 2,
"children": [{
"id": 3
}, {
"id": 12
}
]
}, {
"id": 13
}
]
function parse_tree_2(n) {
return(_und.map(n, parse_tree));
}
function parse_tree(n) {
if (n['children']) {
return({id: n['id'], children: parse_tree_2(n['children'])});
} else {
return({id: n['id']});
}
}
result = _und.map(data, parse_tree);
console.log("Result: %j", result);
You can put that into a file, and execute it with node (by download underscore with nmp install node).
On plain js it would be something like:
<script type="text/javascript" src="http://underscorejs.org/underscore-min.js"></script>
<script type="text/javascript">
data = [{
"id": 1,
"children": [{
"id": 7,
"children": [{
"id": 8,
"children": [{
"id": 4
}, {
"id": 5
}, {
"id": 11
}
]
}, {
"id": 9
}
]
}, {
"id": 6
}, {
"id": 10
}
]
}, {
"id": 2,
"children": [{
"id": 3
}, {
"id": 12
}
]
}, {
"id": 13
}
]
function parse_tree_2(n) {
return(_.map(n, parse_tree));
}
function parse_tree(n) {
if (n['children']) {
return({id: n['id'], children: parse_tree_2(n['children'])});
} else {
return({id: n['id']});
}
}
result = _.map(data, parse_tree);
console.log("Result: %j", result);
</script>
Ruby code:
require 'json'
data = <<EOF
[{
"id": 1,
"children": [{
"id": 7,
"children": [{
"id": 8,
"children": [{
"id": 4
}, {
"id": 5
}, {
"id": 11
}
]
}, {
"id": 9
}
]
}, {
"id": 6
}, {
"id": 10
}
]
}, {
"id": 2,
"children": [{
"id": 3
}, {
"id": 12
}
]
}, {
"id": 13
}
]
EOF
json = JSON.parse(data)
def parse_tree(n)
if n["children"]
{id: n["id"], children: n['children'].map {|c| parse_tree(c)} }
else
{id: n["id"]}
end
end
result = json.map {|n| parse_tree(n) }
puts result