Access Ruby hash variables

ruby hash sinatra
Blaine Kasten picture Blaine Kasten · Apr 24, 2013 · Viewed 36.7k times · Source

I am pretty new to ruby and sinatra but basically I have this route:

put '/user_list/:user_id' do
    puts request.params["model"]
end

and it returns the following

{"password":"36494092d7d5682666ac04f62d624141","username":"nicholas","user_id":106,"firstname":"Nicholas","email":"[email protected]","is_admin":0,"lastname":"Rose","privileges":""}

I am now having a hard time accessing values of each of those. It doesn't really seem to be in hash format so I can't really do 

request.params["model"][:password]

It just returns nil..

I just need to know what I can do to access those variables, or how to configure my request parameters to be in a good format to access variables.

Answer

Charles Caldwell picture Charles Caldwell · Apr 24, 2013

Try request.params["model"]["password"]

A Hash's keys can consist of both symbols and strings. However, a string key is different than a symbol key.

Note the following:

h = {:name => 'Charles', "name" => 'Something else'}
h[:name] #=> 'Charles'
h["name"] #=> 'Something else'

EDIT:

In your particular situation, it appears request.params["model"] returns a string instead of a hash. There is a method String#[] which is a means of getting a substring. 

s = "Winter is coming"
s["Winter"] #=> "Winter"
s["Summer"] #=> nil

This would explain your comments.

There are a couple things you can do to remedy your specific situation. I have found the most simplest way to be using JSON. (I'm sure there are others and maybe those will surface through other answers or through comments.)

require 'json'
hash_of_params = JSON.load(request.params["model"]).to_hash
hash_of_params["password"] #=> "36494092d7d5682666ac04f62d624141"

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