Posting json requests to Ruby on Rails server app – 500 error - ruby-on-rails

Question

I have a Ruby on Rails server application(hosted on Heroku) which is supposed to be able to receive HTTP POST requests with JSON strings and add the JSON objects to the database. There are two database models: thanksgivings and requests.
controller/request_controller.rb:
class RequestsController < ApplicationController
[...]
# POST /requests
# POST /requests.json
def create
#request = Request.new(params[:request])
respond_to do |format|
if #request.save
format.html { redirect_to #request, notice: 'Request was successfully created.' }
format.json { render json: #request, status: :created, location: #request }
else
format.html { render action: "new" }
format.json { render json: #request.errors, status: :unprocessable_entity }
end
end
end
[...]
end
The JSON keys for the different database model objects values should be "thanks" and "request" for the Thankgiving DB model and Request DB model respectively.
model/request.rb:
class Request < ActiveRecord::Base
attr_accessible :request
end
model/thankgiving.rb:
class Thanksgiving < ActiveRecord::Base
attr_accessible :thanks
end
When I post an HTTP request to http://YADA.herokuapp.com/thanksgivings.json everything works fine, but when I send it to .../requests.json, I get a 500 error. If I use a faulty key in the JSON string, the request succeeds, but the value becomes null.
Request 1: (correct request to thanksgiving.json)
POST
Host: http://YADA.herokuapp.com/thanksgivings.json
Content-Type: application/json
Body: {"thanks":"qwerty"}
Request 2: (correct request to request.json – returns 500)
POST
Host: http://YADA.herokuapp.com/requests.json
Content-Type: application/json
Body: {"request":"qwerty"}
Request 3: (faulty key - will succeed: value will be null, key will be "request" in response, database element will be added)
POST
Host: http://YADA.herokuapp.com/requests.json
Content-Type: application/json
Body: {"abc":"qwerty"}
The strange thing is that the two controllers, thanksgivings_controller.rb and requests_controller.rb, are "identical" but their behavior differs.
Anyone knows how to do this successfully?

Answer 1

According to the server logs, there was a NoMethodError – stringify_keys. This question's answer was the solution: undefined method `stringify_keys'
Changing
#request = Request.new(params[:request])
to
#request = Request.new(:request => params[:request])
did the trick.