AJAX POST Request Only Works Once in Safari 5 - ajax

Question

I use my own custom AJAX library (I'm not interested in using jQuery, etc.), which is working flawlessly in the following browsers:
Firefox 7
Chrome 14
IE 8
IE 8 (compatibility mode)
Using my custom AJAX library in the aforementioned browsers, I can make as many AJAX requests as I want, in any order, using GET and/or POST methods, and they all work flawlessly. Since a new AJAX object is created for every request (see code below), I can even have more than one AJAX request process simultaneously with success.
However, in Safari 5 an AJAX POST request only passes POST data to the server if it is the absolute first AJAX request to execute. Even if I execute the exact same AJAX POST request twice in a row, the POST data is only passed to the server during the first request. Here is the JavaScript in my custom AJAX library:
if (!Array.indexOf)
{
Array.prototype.indexOf = function(obj) { for (var i = 0; i < this.length; i++) { if (this[i] == obj) { return i; } } return -1; };
}
function ajaxObject()
{
if (window.ActiveXObject)
{
var activexmodes = ["Msxml2.XMLHTTP", "Microsoft.XMLHTTP"];
for (var i = 0; i < activexmodes.length; i++)
{
try
{
return new ActiveXObject(activexmodes[i]);
}
catch (e)
{
}
}
}
else if (window.XMLHttpRequest)
{
return new XMLHttpRequest();
}
else
{
return false;
}
}
function ajaxRequest(aURI, aContainerId, aPostData, aResponseType, aAvoidBrowserCache)
{
// Initialize
var xmlhttp = new ajaxObject();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200)
{
if (aResponseType != "eval" && aResponseType != "EVAL")
{
// Show HTML for response
document.getElementById(aContainerId).innerHTML = xmlhttp.responseText;
}
else
{
// Parse & execute JavaScript for response
var responseText = xmlhttp.responseText;
var startPos, endPos;
for (var i = 0; i < responseText.length; i++)
{
if (responseText.substring(i, i + 6) == "<eval>")
{
startPos = i + 6;
break;
}
}
for (var i = startPos; i < responseText.length; i++)
{
if (responseText.substring(i, i + 7) == "</eval>")
{
endPos = i;
break;
}
}
textToEval = responseText.substring(startPos, endPos);
eval(textToEval);
}
}
else
{
try
{
if (xmlhttp.status != 0 && xmlhttp.status != 200)
{
alert('Error ' + xmlhttp.status);
}
}
catch (e)
{
// Handle IE8 debug "unknown error"
}
}
}
if (aAvoidBrowserCache != false)
{
// Combat browser caching:
aURI = aURI + (aURI.indexOf("?") == -1 ? "?" : "&");
theTime = new Date().getTime();
aURI = aURI + theTime + "=" + theTime;
}
// Make request
if (typeof aPostData == "undefined" || aPostData == null || aPostData == "")
{
// GET request
xmlhttp.open("GET", aURI, true);
xmlhttp.send();
}
else
{
// POST request
var parameters = "";
if (aPostData.constructor.toString().indexOf("Array") != -1)
{
// Use parameters passed as array
for (var postCount = 0; postCount < aPostData.length; postCount++)
{
if (parameters != "")
{
parameters = parameters + "&";
}
parameters = parameters + aPostData[postCount][0] + "=" + encodeURIComponent(aPostData[postCount][1]);
}
}
else
{
// Use parameters passed as string
parameters = aPostData;
}
xmlhttp.open("POST", aURI, true);
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlhttp.send(parameters);
}
}
So for example, either of the following AJAX POST requests will pass POST data if they are the absolute first AJAX request (whether GET or POST); otherwise, the POST data is not passed:
ajaxRequest("test.aspx", "", [["name1","value1"],["name2","value2"]], "eval");
or
ajaxRequest("test.aspx", "", "name1=value1&name2=value2", "eval");
I have added debug statements all throughout my AJAX library, and the POST parameters are being created in the "parameters" variable as expected prior to each POST request. I have absolutely no idea why, only in Safari 5 (out of the mentioned browsers), I have this problem. Any ideas?
Thanks in advance!
Jesse

Answer 1

The reason the call is failing is because of a bug in Safari when working with Windows Authentication under IIS. Go to the Authentication settings of your website. Right click on Windows Authentication, choose providers and remove Negotiate, leaving NTLM which works fine. I haven't tested Kerberos.
This issue only appears in certain builds of safari.

Answer 2

Came here from the thread you mentioned might be a dupe. I never solved our problem, but have you tried a simple page making post requests? With our issue it's a post problem, not an AJAX problem, we're still stumped though.
What version of IIS are you running on the server?

Answer 3

I can confirm that the problem seems related to some sort of interaction between Safari & IIS. Luckily, I only develop and test this portion of the code on Windows. I moved it unchanged to a LAMP (Linux/Apache) staging server (prior to moving to our LAMP production server) and the problem went away. I was seeing the problem with Safari 5, IIS 5.1, & an ActiveState Perl 5.6 CGI.
Under RHEL 5, Apache 2.2, & Perl 5.8, it is gone.