How to catch curl errors in PHP

When working with PHP curl functions it is always best to know if your curl has failed in any way.

Using the basic PHP curl function below.

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
$result = curl_exec($ch);
if (curl_exec($ch) === false) {
    echo "ok";
} else {
    echo "error";
}
curl_close($ch);

All we have to add in this function is the curl_error() function to detect if there were any errors. Here is a very basic function that can be used below that will also detect HTTP client errors as well.

function curl_error_test($url) {
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

    $responseBody = curl_exec($ch);
    /*
     * if curl_exec failed then
     * $responseBody is false
     * curl_errno() returns non-zero number
     * curl_error() returns non-empty string
     * which one to use is up too you
     */
    if ($responseBody === false) {
        return "CURL Error: " . curl_error($ch);
    }

    $responseCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    /*
     * 4xx status codes are client errors
     * 5xx status codes are server errors
     */
    if ($responseCode >= 400) {
        return "HTTP Error: " . $responseCode;
    }

    return "No CURL or HTTP Error";
}