Sometimes I have this issue of parsing JSON that contains the string representation of Ruby hash for whatever reason.

Problem

It happens obviously because the hash string is not JSON.

require 'json'
hsh_as_str = '{"order_id"=>nil}'
JSON.parse(hsh_as_str)
# JSON::ParserError: 783: unexpected token at '{"order_id"=>nil}'

Solution A

require 'json'
hsh_as_str = '{"order_id"=>nil}'
valid_json = hsh_as_str.gsub('=>', ':').gsub(':nil', ':null')
#=> "{\"order_id\":null}"
JSON.parse(valid_json)
#=> {"order_id"=>nil}

Solution B

require 'json'
hsh_as_str = '{"order_id"=>nil}'
eval(hsh_as_str)
#=> {"order_id"=>nil}

Pitfalls

• It can be more complicated when the string contains the string representation of Ruby objects, for example:

'{"user"=>#<User id=123>}'

That's it.

Resources

• stackoverflow.com/questions/1667630/how-do-..