How to debug curl error messages in php

How to debug curl error information in php: 1. Use the functions [curl_errno] and [curl_error] to return the HTTP error code and error category respectively; 2. Set [CURLOPT_VERBOSE] to true and set it to A file opened with fopen.

How to debug curl error messages in php:

The first method, First What can be used is the curl_errno and curl_error functions, which return the HTTP error code and error category respectively. For example:

<?php
$ch = curl_init(&#39;http://example.com/&#39;);
curl_exec($ch);
if (curl_errno($ch)) {
    echo &#39;Curl error: &#39; . curl_error($ch);
}
curl_close($ch);
?>

Secondly, if you need to get more detailed information, you can use the curl_getinfo function. For example:

<?php
$ch = curl_init(&#39;http://example.com/&#39;);
curl_setopt($ch, CURLINFO_HEADER_OUT, true);
curl_exec($ch);
if (!curl_errno($ch)) {
    print_r(curl_getinfo($ch));
}
curl_close($ch);
?>

After setting the CURLINFO_HEADER_OUT option, the array returned by the curl_getinfo function will contain the header information of the cURL request. To see the response header information, you can set the CURLOPT_HEADER option to true in curl_setopt.

curl_exec When the function is executed successfully, the response body information will be processed according to the value of the CURLOPT_RETURNTRANSFER option: if it is true, it will be returned as a string, if it is false, it will be directly output. The result is FALSE if execution fails. That is to say, if the execution fails (assuming it is a 400 error), the response text (which may contain more specific error information) cannot be seen from the result of the curl_exec function. There are two ways to see the response text. The first method is to set 400 as the success code. The example is as follows:

curl_setopt($ch, CURLOPT_FAILONERROR, false);
curl_setopt($ch, CURLOPT_HTTP200ALIASES, array(400));

The second method is to set CURLOPT_VERBOSE to true and CURLOPT_STDERR is set to a file opened with fopen. In this way cURL will record all interaction information with the server into this file.

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