Parsing a JSON string in Ruby

Question

I have a string that I want to parse in Ruby:

string = '{"desc":{"someKey":"someValue","anotherKey":"value"},"main_item":{"stats":{"a":8,"b":12,"c":10}}}' 

Is there an easy way to extract the data?

Answer 1

This looks like JavaScript Object Notation (JSON). You can parse JSON that resides in some variable, e.g. json_string, like so:

require 'json' JSON.parse(json_string) 

If you’re using an older Ruby, you may need to install the json gem.

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There are also other implementations of JSON for Ruby that may fit some use-cases better:

• YAJL C Bindings for Ruby
• JSON::Stream

Answer 2

Just to extend the answers a bit with what to do with the parsed object:

# JSON Parsing example require "rubygems" # don't need this if you're Ruby v1.9.3 or higher require "json"  string = '{"desc":{"someKey":"someValue","anotherKey":"value"},"main_item":{"stats":{"a":8,"b":12,"c":10}}}' parsed = JSON.parse(string) # returns a hash  p parsed["desc"]["someKey"] p parsed["main_item"]["stats"]["a"]  # Read JSON from a file, iterate over objects file = open("shops.json") json = file.read  parsed = JSON.parse(json)  parsed["shop"].each do |shop|   p shop["id"] end