How to send JSON form data with Mechanize or Farad

Question

I want to retrieve data from a website that uses JSON data to set custom search parameters which seem to be requested via AJAX. The data transmitted shows up under XHR->Request Payload in Firebug:

{"filters": [{"action": "post", "filterName": "Hersteller", "ids": [269], 
"settingName": "Hersteller", "settingValue": "ValueA"}, 
{"action": "delete", "filterName": "Modelle", 
"settingName": "Modelle", "settingValue": ""}]}

The site doesn't transmit any POST parameters but only this JSON encoded data to apply search criteria. Passing this data as post parameters with Mechanize doesn't work.

How can this data be transmitted using Mechanize or Faraday in Ruby on Rails?

Answer 1

I figured out a way to do this:

connection = Faraday.new

fetched_page = connection.post do |request|
  request.url 'http://www.site.com'
  request.headers['Content-Type'] = 'application/json'
  request.body = '{"filters": [{"action": "post", "filterName": "Hersteller", "ids": [269], 
"settingName": "Hersteller", "settingValue": "ValueA"}, {"action": "delete", "filterName": "Modelle", "settingName": "Modelle", "settingValue": ""}]}'
end

Answer 2

With Mechanize you would do:

agent.post url, data.to_json, {'Content-Type' => 'application/json'}