jQuery $.ajax(), $.post sending “OPTIONS” as REQUEST_METHOD in Firefox

Question

Having trouble with what I thought was a relatively simple jQuery plugin...

The plugin should fetch data from a php script via ajax to add options to a

Answer 1

Check if your form's action URL includes the www part of the domain, while the original page you have opened is viewed without www.

Typically done for Canonical Urls..

I struggled for hours before stumbling upon this article and found the hint of Cross Domain.

Answer 2

I had a similar problem with trying to use the Facebook API.

The only contentType which didn't send the Preflighted request seemed to be just text/plain... not the rest of the parameters mentioned at mozilla here

• Why is this the only browser which does this?
• Why doesn't Facebook know and accept the preflight request?

FYI: The aforementioned Moz doc suggests X-Lori headers should trigger a Preflighted request ... it doesn't.

Answer 3

Please be advised:

JSONP supports only the GET request method.

*Send request by firefox:*

$.ajax({
   type: 'POST',//<<===
   contentType: 'application/json',
   url: url,
   dataType: "json"//<<=============
    ...
});

Above request send by OPTIONS(while ==>type: 'POST')!!!!

$.ajax({
    type: 'POST',//<<===
    contentType: 'application/json',
    url: url,
    dataType: "jsonp"//<<==============
    ...
});

But above request send by GET(while ==>type: 'POST')!!!!

When you are in "cross-domain communication" , pay attention and be careful.

Answer 4

I used a proxy url to solve a similar problem when I want to post data to my apache solr hosted in another server. (This may not be the perfect answer but it solves my problem.)

Follow this URL: Using Mode-Rewrite for proxying, I add this line to my httpd.conf:

 RewriteRule ^solr/(.*)$ http://ip:8983/solr$1 [P]

Therefore, I can just post data to /solr instead of posting data to http://ip:8983/solr/*. Then it will be posting data in the same origin.

Answer 5

This mozilla developer center article describes various cross-domain request scenarios. The article seems to indicate that a POST request with content type of 'application/x-www-form-urlencoded' should be sent as a 'simple request' (with no 'preflight' OPTIONS request). I found , however, that Firefox sent the OPTIONS request, even though my POST was sent with that content type.

I was able to make this work by creating an options request handler on the server, that set the 'Access-Control-Allow-Origin' response header to '*'. You can be more restrictive by setting it to something specific, like 'http://someurl.com'. Also, I have read that, supposedly, you can specify a comma-separated list of multiple origins, but I couldn't get this to work.

Once Firefox receives the response to the OPTIONS request with an acceptable 'Access-Control-Allow-Origin' value, it sends the POST request.

Answer 6

Culprit is preflight request using OPTIONS method

For HTTP request methods that can cause side-effects on user data (in particular, for HTTP methods other than GET, or for POST usage with certain MIME types), the specification mandates that browsers "preflight" the request, soliciting supported methods from the server with an HTTP OPTIONS request method, and then, upon "approval" from the server, sending the actual request with the actual HTTP request method.

Web specification refer to: https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS

I resolved the problem by adding following lines in Nginx conf.

    location / {
               if ($request_method = OPTIONS ) {
                   add_header Access-Control-Allow-Origin  "*";
                   add_header Access-Control-Allow-Methods "POST, GET, PUT, UPDATE, DELETE, OPTIONS";
                   add_header Access-Control-Allow-Headers "Authorization";
                   add_header Access-Control-Allow-Credentials  "true";
                   add_header Content-Length 0;
                   add_header Content-Type text/plain;
                   return 200;
               }
    location ~ ^/(xxxx)$ {
                if ($request_method = OPTIONS) {
                    rewrite ^(.*)$ / last;
                }
    }