I have the same code running on multiple sites/servers. 2 days ago the code started returning http_code = 0 and the error message "empty reply from server" on one of the servers.
Can anyone shed any light as to why a particular server would be working one day, then not working the next? I have submitted a ticket to the ISP explaining the issue but they cannot seem to find what is wrong (yet).
I guess the question really is, what would/could change on a server to stop this from working?
What is interesting tho is the url I am referencing doesnt get touched on the server returning the error. If I change the url to point to something that doesnt exist, the same error is returned. So it appears that CURL POST references in total are being rejected by the server. I currently have other CURL scripts that are hitting these problem sites that are still working, but they do not have POST options in them.
The issue is definitely related to CURL POST requests on this server, and they are being rejected pretty much immediately.
On the server in question I have 15+ separate accounts and every one of them returns the same result so I dont think its anything I have changed as I know I havent made any wholesale changes to ALL the sites at the time when this issue arose. Of the 6 other sites I have hosted elsewhere, everything is still working fine with exactly the same code.
I have tried various combinations/changes to options from posts I have read but nothing has really made a difference, the working sites still work and the non-working sites still dont.
function sendWSRequest($url, $xml) {
// $headers[] = 'Content-Type: application/xml; charset=utf-8';
$headers[] = 'Content-Type: text/xml; charset=utf-8';
$headers[] = 'Content-Length: ' . strlen($xml);
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_HEADER, true);
// curl_setopt($ch, CURLINFO_HEADER_OUT, false);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_POSTFIELDS, $xml);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
// curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
// curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 20);
$result = curl_exec($ch);
if($result===false) {
print 'error with curl - '.curl_error($ch).'<br />';
}
$info = curl_getinfo($ch);
curl_close($ch);
return $result;
}
Any help would be greatly appreciated.
EDIT To summarise based on further investigations, when the script errors, nothing registers in the server access logs. So it appears that CURL requests containing POST options are being rejected before access is granted/logged...
Cheers
Greg J
According to the PHP manual, upload should be urlencoded:
CURLOPT_POSTFIELDS The full data to post in a HTTP "POST" operation. [...] This parameter can either be passed as a urlencoded string like 'para1=val1¶2=val2&...' or as an array with the field name as key and field data as value. If value is an array, the Content-Type header will be set to multipart/form-data. As of PHP 5.2.0, value must be an array if files are passed to this option with the @ prefix. As of PHP 5.5.0, the @ prefix is deprecated and files can be sent using CURLFile.
So you might try with
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_HEADER, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, 'xml=' . urlencode($xml));
and see what happens. Or, anyway, start with an empty or very simple FIELD to see if it at least arrives to the destination server.
I've checked this setup on a test machine and it works. The problem is then likely not to be PHP or cURL side at all, at this point. Can you request a list of software/hardware updates on that machine and network in the last days?
Otherwise, I'd try to capture outgoing traffic so as to determine whether the request leaves the server (and the problem is in between, e.g. a misconfigured firewall: hence my inclusion of "hardware" in the change list), or doesn't leave the server at all. In this latter case the culprits could be:
OK, as it turns out, a rather reluctant host recompiled Apache2 and PHP which has resolved the issue.
The host claims (their opening statement to my support ticket) that no updates to either Apache2 or PHP had been performed around the time the issue occurred.
the behavior was as such that it wasnt even acknowledging a CURL request that contained the POST commands. The target URL was never reached.
Thank you so much to all who provided their advice. Particularly Isemi who has gone to great lengths to find a resolution.
I know this is an old thread, but I found a solution that may save someone else a headache:
I just began encountering this exact problem with a web site hosted at GoDaddy which was working until recently. To investigate the problem I created an HTML page with a form containing the same fields being submitted in the POST data via cURL.
The browser-submitted HTML form worked while the cURL POST resulted in the Empty reply from server error. So I examined the difference between the headers submitted by the browser and those submitted by cURL using the PHP apache_request_headers() function on my development system where both the cURL and browser submissions worked.
As soon as I added the "User-Agent" header submitted by my browser to the cURL POST, the problem site worked as expected instead of returning an empty reply:
CURLOPT_HTTPHEADER =>
array("User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Firefox/31.0")
I did not experiment with other/simpler User-Agent headers since this quick fix solved my problem.