Post request to eventbrite API via uri in rails - ruby-on-rails

Question

I'd like to send a post request via URI to the eventbrite API in order to receive a user access key. Documented here: https://www.eventbrite.com/developer/v3/reference/authentication/
You must then exchange this access code for an OAuth token. Send a
POST request to:
https://www.eventbrite.com/oauth/token This POST must contain the
following urlencoded data, along with a Content-type:
application/x-www-form-urlencoded header:
code=THE_USERS_AUTH_CODE&client_secret=YOUR_CLIENT_SECRET&client_id=YOUR_API_KEY&grant_type=authorization_code
I try to translate that into rails and sending a post request via URI. The response is expected to be the authorization code:
require "uri"
require "net/http"
params = {'code' => current_user.eventbrite_key, 'client_secret' => 'XXXX', 'client_id' => 'XXXX', 'grant_type' => 'authorization_code' }
response = Net::HTTP.post_form(URI.parse('https://www.eventbrite.com/oauth/token'), params)
This isn't working (http bad request).
I researched that the default content type is already "application/x-www-form-urlencoded" so I would not have to define that in my request. The 'code' should be correct as I simply fetch it before with help of their callback URL. Other credentials should also be correct.
The response is the following:
<Net::HTTPBadRequest:0x007ff8fcc9e4b8>
"{\"server\":[\"nginx\"],\"date\":[\"Wed, 08 Jul 2015 14:48:19
GMT\"],\"content-type\":[\"application/json\"],\"transfer-encoding\":[\"chunked\"],\"connection\":[\"keep-alive\"],\"x-xss-protection\":[\"1;
mode=block\"],\"x-content-type-options\":[\"nosniff\"],\"x-ua-compatible\":[\"IE=edge\"],\"p3p\":[\"CP=\\"NOI
ADM DEV PSAi COM NAV OUR OTRo STP IND
DEM\\"\"],\"x-frame-options\":[\"SAMEORIGIN\"],\"set-cookie\":[\"mgrefby=;
Domain=.eventbrite.com; expires=Thu, 07-Jul-2016 14:48:19 GMT;
httponly; Max-Age=31536000;
Path=/\",\"G=v%3D2%26i%3D54a93968-6bc1-486a-b401-fedab0b33dc4%26a%3D5f9%26s%3D56f73cc9c4519dc0d05f6518a092e66c6c83516c;
Domain=.eventbrite.com; expires=Thu, 07-Jul-2016 14:48:19 GMT;
httponly; Path=/\",\"ebEventToTrack=; expires=Thu, 01-Jan-1970
00:00:00 GMT; Max-Age=0;
Path=/\",\"SS=AE3DLHS8ESSoJhhYoWTny-enqBu_PN4d5A;
Domain=.eventbrite.com; httponly; Path=/;
secure\",\"eblang=lo%3Den_US%26la%3Den-us; Domain=.eventbrite.com;
expires=Thu, 07-Jul-2016 14:48:19 GMT; httponly; Path=/\",\"AN=;
expires=Thu, 01-Jan-1970 00:00:00 GMT; Max-Age=0;
Path=/\",\"mgref=typeins; Domain=.eventbrite.com; expires=Thu,
07-Jul-2016 14:48:19 GMT; httponly; Max-Age=31536000;
Path=/\",\"SP=AGQgbblORi0c9X3owNbUIuFSZeUwSlY9HoUdpypGreork-Gf0GI6rzrLrcQDGWvu49mxHIQW9iBqa6JR-1k0eGvBhwnNpaON_Aak96kQ1yu90CaN7P2lnvfddxfskEniVHppbf0rp8YL5PA4vLYzRiaWdSohVy73j8H6HlCakht1OfKyxvwG-FeyR5rwPFEJw0iGB71Azw3oyFOTJcGJcYMWdSSVgS3F6pEbV5QI4ps5WlNMW0C9uL0;
Domain=.eventbrite.com; httponly; Path=/\",\"SERVERID=djc11;
path=/\"]}"
URI.parse('https://www.eventbrite.com/oauth/token') without params returns:
{"scheme":"https","user":null,"password":null,"host":"www.eventbrite.com","port":443,"path":"/oauth/token","query":null,"opaque":null,"fragment":null,"parser":{"regexp":{"SCHEME":"(?-mix:\A[A-Za-z][A-Za-z0-9+\-.]\z)","USERINFO":"(?-mix:\A(?:%\h\h|[!$\u0026-.0-;=A-Z_a-z~])\z)","HOST":"(?-mix:\A(?:(?\u003cIP-literal\u003e\[(?:(?\u003cIPv6address\u003e(?:\h{1,4}:){6}(?\u003cls32\u003e\h{1,4}:\h{1,4}|(?\u003cIPv4address\u003e(?\u003cdec-octet\u003e[1-9]\d|1\d{2}|2[0-4]\d|25[0-5]|\d)\.\g\u003cdec-octet\u003e\.\g\u003cdec-octet\u003e\.\g\u003cdec-octet\u003e))|::(?:\h{1,4}:){5}\g\u003cls32\u003e|\h{,4}::(?:\h{1,4}:){4}\g\u003cls32\u003e|(?:(?:\h{1,4}:)?\h{1,4})?::(?:\h{1,4}:){3}\g\u003cls32\u003e|(?:(?:\h{1,4}:){,2}\h{1,4})?::(?:\h{1,4}:){2}\g\u003cls32\u003e|(?:(?:\h{1,4}:){,3}\h{1,4})?::\h{1,4}:\g\u003cls32\u003e|(?:(?:\h{1,4}:){,4}\h{1,4})?::\g\u003cls32\u003e|(?:(?:\h{1,4}:){,5}\h{1,4})?::\h{1,4}|(?:(?:\h{1,4}:){,6}\h{1,4})?::)|(?\u003cIPvFuture\u003ev\h+\.[!$\u0026-.0-;=A-Z_a-z~]+))\])|\g\u003cIPv4address\u003e|(?\u003creg-name\u003e(?:%\h\h|[!$\u0026-.0-9;=A-Z_a-z~])))\z)","ABS_PATH":"(?-mix:\A\/(?:%\h\h|[!$\u0026-.0-;=#-Z_a-z~])(?:\/(?:%\h\h|[!$\u0026-.0-;=#-Z_a-z~]))\z)","REL_PATH":"(?-mix:\A(?:%\h\h|[!$\u0026-.0-;=#-Z_a-z~])+(?:\/(?:%\h\h|[!$\u0026-.0-;=#-Z_a-z~]))\z)","QUERY":"(?-mix:\A(?:%\h\h|[!$\u0026-.0-;=#-Z_a-z~\/?])\z)","FRAGMENT":"(?-mix:\A(?:%\h\h|[!$\u0026-.0-;=#-Z_a-z~\/?])\z)","OPAQUE":"(?-mix:\A(?:[^\/].)?\z)","PORT":"(?-mix:\A[\x09\x0a\x0c\x0d
]\d*[\x09\x0a\x0c\x0d ]*\z)"}}}