Question

Hello I need to make json requests from Backbone to an API (I have control over server-side)..
I keep getting the Access-Control-Allow-Origin, although response headers looks fine.

Here are Nginx settings:

location / {
     if ($request_method = 'OPTIONS') {
        add_header 'Access-Control-Allow-Origin' '*';
        add_header 'Access-Control-Allow-Credentials' 'true';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        add_header 'Access-Control-Allow-Headers' 'DNT,X-Mx-ReqToken,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
        add_header 'Access-Control-Max-Age' 1728000;
        add_header 'Content-Type' 'text/plain charset=UTF-8';
        add_header 'Content-Length' 0;
        return 204;
     }
     if ($request_method = 'POST') {
        add_header 'Access-Control-Allow-Origin' '*';
        add_header 'Access-Control-Allow-Credentials' 'true';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        add_header 'Access-Control-Allow-Headers' 'DNT,X-Mx-ReqToken,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
     }
     if ($request_method = 'GET') {
        add_header 'Access-Control-Allow-Origin' '*';
        add_header 'Access-Control-Allow-Credentials' 'true';
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
        add_header 'Access-Control-Allow-Headers' 'DNT,X-Mx-ReqToken,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type';
     }
passenger_enabled on;
} 

here are the request / response headers from console:

Request headers
DNT: 1
X-Requested-With: XMLHttpRequest
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_5) AppleWebKit/534.57.7 (KHTML, like Gecko) Version/5.1.7 Safari/534.57.7
Accept: */*;q=0.5, text/javascript, application/javascript, application/ecmascript, application/x-ecmascript
Referer: http://<address>/

Response Headers
Access-Control-Request-Method: *
X-Powered-By: Phusion Passenger (mod_rails/mod_rack) 3.0.14
Transfer-Encoding: Identity
Status: 200
Connection: keep-alive
X-Request-Id: 2917f130c8699182ee9cdc047c1926fe
X-UA-Compatible: IE=Edge,chrome=1
X-Runtime: 0.455212
Server: nginx/1.2.2 + Phusion Passenger 3.0.14 (mod_rails/mod_rack)
Etag: "346cee46bab7061e866fa064df95c845"
Content-Type: text/html; charset=utf-8
Access-Control-Allow-Origin: *
Cache-Control: max-age=0, private, must-revalidate
Set-Cookie: _y_app_session=BAh7CEkiD3Nlc3Npb25faWQGOgZFRkkiJWE2Zjg3YWQ0NDFjZWNiM2VmNTg2ZDhiYmIyOGFlYmIwBjsAVEkiEF9jc3JmX3Rva2VuBjsARkkiMUxBSzFKTDJQWG1sa2dhbXRLM2ptQmxjenRkZEdJeVh1MDFhaUVuaXE1dFE9BjsARkkiCmZsYXNoBjsARm86JUFjdGlvbkRpc3BhdGNoOjpGbGFzaDo6Rmxhc2hIYXNoCToKQHVzZWRvOghTZXQGOgpAaGFzaHsAOgxAY2xvc2VkRjoNQGZsYXNoZXN7CDoLbm90aWNlMDoLZXJyb3JzMDoKZXJyb3IwOglAbm93MA%3D%3D--648ffcb1b2869f1da57773459307ca1ac5fb8bfb; path=/; HttpOnly
Access-Control-Allow-Headers: *

* UPDATE *

I am currently using http://github.com/yaoweibin/nginx_cross_origin_module and it allows me to make requests from console.

I have set up the nginx as in instructions in the repo above.

    cors on;
    cors_max_age     3600;
    cors_origin_list unbounded;
    cors_method_list GET HEAD PUT POST;
    cors_header_list unbounded;

    server {
     ## Server stuff.. 
     # passenger stuff
   }

So I can do:

 var xhr = new XMLHttpRequest()
 xhr.open('GET', 'http://www.api.com/plots.json')
 xhr.send();

When I do fetch via Backbone with the model that has ‘http://www.api.com/plots.json’ as url I get Same origin errors.

** UPDATE **

So I switched to more_set_headers and can do .fetch() now… Still cannot make POST or do collection.create();

Here is the latest Nginx setup:

server {

              listen 80;
              server_name api.app.com;
              root /home/ubuntu/app/current/public;
              passenger_enabled on;


    location / {
        if ($request_method = 'OPTIONS') {
             more_set_headers 'Access-Control-Allow-Origin: *';
             more_set_headers "Access-Control-Allow-Methods: OPTIONS, GET, PUT, DELETE, POST";
             more_set_headers "Access-Control-Allow-Headers:  x-requested-with";
             more_set_headers "Access-Control-Max-Age: 1728000";
             more_set_headers 'Content-Type: text/plain; charset=UTF-8';
             more_set_headers 'application/json; charset=utf-8';
             return 200;
            }

          if ($request_method = 'POST') {
           more_set_headers "Access-Control-Allow-Origin: http://vidoai.com";
           more_set_headers "Access-Control-Allow-Methods: GET, POST, OPTIONS";
           more_set_headers 'Access-Control-Allow-Headers: DNT, X-Mx-ReqToken, Keep-Alive,  User-Agent, X-Requested-With, If-Modified-Since, Cache-Control, Content-Type';
           more_set_headers 'Content-Type: application/json, text/javascript,  */*';
         }


passenger_enabled on;
    }


        if ($request_method !~ ^(GET|HEAD|POST|PUT|DELETE)$ ) {
           return 444;  # block requests that Rails doesn't handle
          }





}

What am I missing??

Answer 1

In this line:

if ($request_method !~ ^(GET|HEAD|POST|PUT|DELETE)$ ) {}

You should add OPTIONS too because that is what Backbone would be using probably and you have it defined in your location as well.