PHP cURL timeout

cURL is a library for PHP that allows you to connect and communicate with servers using different protocols. One of its most useful features is the ability to set timeouts for requests, which can help prevent your script from waiting too long for a response.

Setting a timeout

To set a timeout for a cURL request in PHP, you can use the CURLOPT_TIMEOUT option. This option sets the maximum amount of time that cURL will wait for a response before timing out.

// create a new cURL resource
$ch = curl_init();

// set the URL and other options
curl_setopt($ch, CURLOPT_URL, "http://example.com");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_TIMEOUT, 10); // set timeout to 10 seconds

// execute the request and get the response
$response = curl_exec($ch);

// close cURL resource
curl_close($ch);

In the example above, we set the timeout to 10 seconds using the CURLOPT_TIMEOUT option. If the request takes longer than 10 seconds to complete, cURL will return with an error.

You can also set a separate timeout for the connection phase of the request using the CURLOPT_CONNECTTIMEOUT option. This sets the maximum amount of time that cURL will wait for the server to respond before giving up and returning an error.

// create a new cURL resource
$ch = curl_init();

// set the URL and other options
curl_setopt($ch, CURLOPT_URL, "http://example.com");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_TIMEOUT, 10); // set timeout to 10 seconds
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 5); // set connect timeout to 5 seconds

// execute the request and get the response
$response = curl_exec($ch);

// close cURL resource
curl_close($ch);

In the example above, we set the CURLOPT_CONNECTTIMEOUT option to 5 seconds. If the server does not respond within 5 seconds, cURL will give up and return an error. If the connection is successful, the CURLOPT_TIMEOUT option will apply during the rest of the request.

Handling timeouts

When a cURL request times out, it will return with an error code. You can check for these error codes using curl_errno() and curl_error().

// create a new cURL resource
$ch = curl_init();

// set the URL and other options
curl_setopt($ch, CURLOPT_URL, "http://example.com");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_TIMEOUT, 10); // set timeout to 10 seconds

// execute the request and get the response
$response = curl_exec($ch);

// check for errors
if(curl_errno($ch)) {
    $error_message = curl_error($ch);
    echo "cURL error ({$error_message})";
}

// close cURL resource
curl_close($ch);

In the example above, we use curl_errno() to check for any error codes returned by cURL. If there is an error, we use curl_error() to get the error message and display it to the user.

Conclusion

Setting a timeout for cURL requests in PHP is a simple and effective way to prevent your script from waiting too long for a response. By using the CURLOPT_TIMEOUT and CURLOPT_CONNECTTIMEOUT options, you can set separate timeouts for the request and connection phases of the request. When a timeout occurs, you can use curl_errno() and curl_error() to handle the error and display a message to the user.