I'm using Prototype bined with CodeIgniter to submit an AJAX request. My browser is Chrome. I'm receiving an error in the console that reads "Refused to set Unsafe Header: Connection". Here is the Ajax Request line:

new Ajax.Request('/vbs/index.php/signup/get_ratecenters',{method:'POST', evalScripts:true})

I've attempted to set the type to synchronous, but received the same error.

Can someone assist? Thanks in advance.

I'm using Prototype bined with CodeIgniter to submit an AJAX request. My browser is Chrome. I'm receiving an error in the console that reads "Refused to set Unsafe Header: Connection". Here is the Ajax Request line:

new Ajax.Request('/vbs/index.php/signup/get_ratecenters',{method:'POST', evalScripts:true})

I've attempted to set the type to synchronous, but received the same error.

Can someone assist? Thanks in advance.

• php
• javascript
• ajax
• codeigniter
• prototypejs

2 Answers 2

There's only one code fragment in prototype.js (1.7.0.0) that attempts to set a Connection: close header

if (this.method == 'post') {
  headers['Content-type'] = this.options.contentType +
    (this.options.encoding ? '; charset=' + this.options.encoding : '');

  /* Force "Connection: close" for older Mozilla browsers to work
   * around a bug where XMLHttpRequest sends an incorrect
   * Content-length header. See Mozilla Bugzilla #246651.
   */
  if (this.transport.overrideMimeType &&
      (navigator.userAgent.match(/Gecko\/(\d{4})/) || [0,2005])[1] < 2005)
        headers['Connection'] = 'close';
}

If you're using a local copy of prototype.js you could change the code fragment to

if (this.method == 'post') {
  headers['Content-type'] = this.options.contentType +
    (this.options.encoding ? '; charset=' + this.options.encoding : '');

  /* Force "Connection: close" for older Mozilla browsers to work
   * around a bug where XMLHttpRequest sends an incorrect
   * Content-length header. See Mozilla Bugzilla #246651.
   */
  if (this.transport.overrideMimeType &&
      (navigator.userAgent.match(/Gecko\/(\d{4})/) || [0,2005])[1] < 2005)
  {
        alert("Yes, this is it.");
            if ( navigator.userAgent.match(/Gecko\/(\d{4})/) ) {
                alert("navigator");
            }
        headers['Connection'] = 'close';
  }
}

and see if it's really the cause.

What happens if you load /vbs/index.php/signup/get_ratecenters directly in your browser?

I read somewhere online that "Refused to set Unsafe Header: Connection" is a warning that the HTTP "Connection" header cannot be set, but doesn't mean the request will not be processed, so it's possible something else is going on here?

Check /vbs/index.php/signup/get_ratecenters and make sure it returns valid JavaScript code. Execute that code in the Chrome console and make sure it is error free... possibly here's a different error here.