How to handle json data request?

rubyonrails-talk
1

I have searched in this group for a while, and it seems no one face the same problem like me yet. I am developing a rest web service(post method) that requires json data format from my javascript client application. I don't know how to handle since I could not get data that is being sent. In my controller, params variable got messed with key and value. I want to know the way how to parse data from this to ruby object. Any idea is really appreciated.

2

Get the JSON gem for starters.

   sudo gem install json

Then in your code:    require 'rubygems'    gem 'json'    require 'json'

-Rob

Rob Biedenharn http://agileconsultingllc.com Rob@AgileConsultingLLC.com

3

I have followed what you said, but still doesn't work. The params variable still contains weird string like: {"{\"first_name\":\"chamnap \",\"last_name\":\"chhorn\"}"=>nil, "action"=>"create", "controller"=>"users"}. Therefore, I could not access through either params[:first_name] or params[:last_name].

Chamnap

4

Get the JSON gem for starters.

   sudo gem install json

Then in your code:    require 'rubygems'    gem 'json'    require 'json'

I have followed what you said, but still doesn't work. The params variable still contains weird string like: {"{\"first_name\":\"chamnap \",\"last_name\":\"chhorn\"}"=>nil, "action"=>"create", "controller"=>"users"}. Therefore, I could not access through either params[:first_name] or params[:last_name].

Chamnap

require 'rubygems'

=> true

gem 'json'

=> true

require 'json'

=> true

raw = "{\"first_name\":\"chamnap\",\"last_name\":\"chhorn\"}"

=> "{\"first_name\":\"chamnap\",\"last_name\":\"chhorn\"}"

puts raw

{"first_name":"chamnap","last_name":"chhorn"} => nil

JSON(raw)

=> {"first_name"=>"chamnap", "last_name"=>"chhorn"}

cooked = JSON.parse(raw)

=> {"first_name"=>"chamnap", "last_name"=>"chhorn"}

raw

=> "{\"first_name\":\"chamnap\",\"last_name\":\"chhorn\"}"

cooked

=> {"first_name"=>"chamnap", "last_name"=>"chhorn"}

raw.class

=> String

cooked.class

=> Hash

cooked["first_name"]

=> "chamnap"

cooked[:first_name]

=> nil

Note that JSON.parse is going to return a normal Ruby Hash, not a Rails ActiveSupport HashWithIndifferentAccess. You'll have to use "first_name" as the key, not :first_name. Show the code that you're trying to use that's pulling that whole string into a key of the params hash.

-Rob

Rob Biedenharn http://agileconsultingllc.com Rob@AgileConsultingLLC.com

5

Thanks

I also have founded a method in ActiveSupport::JSON.decode, and it does work the same thing as you did show me. What do you think?

Chamnap