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I have a laravel project that makes a cURL request to a Canvas API endpoint. This project runs perfectly on my virtual machine. But on the centOS 7 server I've ported it to, its cURL requests don't work at all.
I get the following errors:
curl_getinfo($curl, CURLINFO_HTTP_CODE) returns curl error number 0. From what research I've done, this implies the server is refusing the connection
curl_exec($curl) returns false.
a dd of $curl or $resp dd($curl) returns a very empty string.
Below are some sample curl functions I use:
//NOTE: $this->headers = ["Authorization: Bearer " . myServerAccessToken];
//sets URL and $curl
public function getAdmins() {
$adminsURL = "https://my.test.instructure.com/api/v1/accounts/1/admins?per_page=20";
$curl = curl_init();
self::requestCurl($curl, $adminsURL, $this->headers);
$resp = curl_exec($curl);
dd($resp); //shows false
return self::setHeaders($curl);
}
//something missing here?
public function requestCurl($curl, $url, $headers) {
return curl_setopt_array($curl, [
CURLOPT_RETURNTRANSFER => TRUE,
CURLINFO_HEADER_OUT => TRUE,
CURLOPT_URL => $url,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_SSL_VERIFYPEER => TRUE,
CURLOPT_HTTPHEADER => $headers,
CURLOPT_CUSTOMREQUEST => 'GET',
CURLOPT_HEADER => TRUE
]);
}
//returns "curl errno: 0"
public function setHeaders($curl) {
$resp = curl_exec($curl);
$header_size = curl_getinfo( $curl, CURLINFO_HEADER_SIZE );
$header = substr( $resp, 0, $header_size );
$body = substr( $resp, $header_size); //$header_size
$code = curl_getinfo($curl, CURLINFO_HTTP_CODE);
if (curl_getinfo($curl, CURLINFO_HTTP_CODE) != 200) {
echo "<h3>Curl errno: " . curl_getinfo($curl, CURLINFO_HTTP_CODE) . "</h3>";
dd($body); //EMPTY.
return null; //TODO error handling (I think returning null will be enough?)
}
$data = json_decode($body, true);
return $data;
}
Can anyone suggest why this might be happening, and what I could try to fix it? Any advice would be appreciated
Typically CURL error 0 means (host no found). Are you behind a firewall? Can you run this code outside the server. Things to note, is your url redirecting? You'll need to make it follow via CURLOPT_FOLLOWLOCATION = true. Don't forget to set the CURLOPT_MAXREDIRS to say 10 or whatever your comfortable with.
You could try bumping up the timeout limit?
Additionally use curl_error after the exec call to find the hidden errors;
print curl_error($ch);
check FIRST curl is installed on Centos 7 or NOT?
please run command curl -V .
cURL is definitely installed, curl -V works fine
@braunson curl_error($ch) gave me the following:
Failed connect to my.test.instructure.com:443; Operation now in progress
From what I've read, it seems this is a timeout error?
I think it might be the program being behind a firewall. How can I check if it is?
please check your hosts settings reference link: https://stackoverflow.com/questions/45554344/curl-7-failed-to-connect-to-port-80-and-443-on-one-domain/48617092
Thank you for that. I tried both commands. To the curl --ipv4 -v "https://my.test.instructure.com/api/v1/accounts/1/admins?per_page=20" command, I got a full cURL log trace. Of the lines there, these two stood out:
HTTP/1.1 401 Unauthorized
...
"status":"unauthenticated","errors":[{"message":"user authorisation required"}
A check of my /etc/hosts file read like this:
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
143.239.2.37 buzzi buzzi.website.com
What exactly should be there instead?
As a followup to this, I've replaced buzzi with a different, matching server:
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
10.65. myServer myServer.website.com
However, I still have a curl error number zero. This method here:
//gets the data from a successful curl request, and returns said data
public function setHeaders($curl) {
echo "<h1>SetHeaders()</h1>";
$resp = curl_exec($curl);
$header_size = curl_getinfo( $curl, CURLINFO_HEADER_SIZE );
$header = substr( $resp, 0, $header_size );
$body = substr( $resp, $header_size); //$header_size
$code = curl_getinfo($curl, CURLINFO_HTTP_CODE);
if (curl_getinfo($curl, CURLINFO_HTTP_CODE) != 200) {
echo "<h3>Curl errno: " . curl_getinfo($curl, CURLINFO_HTTP_CODE) . "</h3>";
echo "<h3>Curl error(): " . curl_error($curl) . "</h3>";
dd($body);
return null;
}
$data = json_decode($body, true);
return $data;
}
This gives me the following output on the screen:
"SetHeaders()"
"Curl errno: 0"
"Curl error(): Failed connect to my.test.instructure.com:443; Operation now in progress"
"" [dd($body) returns an empty string]
I am trying to understand the curl error message: what does 443 mean? And why would a cURL request that succeeds on my local machine fail when coming from my server?
Any help would be very valuable.
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