PHP - How to add content to the log?

Question

The log points error of undefined variables and functions. But it is not constant (error/s).

These variables are defined through POST, so if a GET is made the error is generated.

Analyzing the file individually it contains neither syntax nor logic errors, but daily the error repeats.

I would like to know the path the user makes to generate the error.

There is a way to add at the end of every log record the last page accessed by the user ? Looking for found error_prepend_string and error_handler

The result I want to get is something like :

Call to undefined function have_posts() in D:\home\site\index.php on line 22 - **ultima pagina visitada .com.br**

What I must do to get this result ?

Answer 1

You can use set_error_handler to generate customized error messages for all levels or only those that interest you. This function is called before the standard PHP error handling.

Example of the manual (reduced):

// error handler function
function myErrorHandler($errno, $errstr, $errfile, $errline)
{
    if (!(error_reporting() & $errno)) {
        // This error code is not included in error_reporting, so let it fall
        // through to the standard PHP error handler
        return false;
    }

    switch ($errno) {
    case E_USER_ERROR:
        echo "<b>My ERROR</b> [$errno] $errstr<br />\n";
        echo "  Fatal error on line $errline in file $errfile";
        echo ", PHP " . PHP_VERSION . " (" . PHP_OS . ")<br />\n";
        echo "Aborting...<br />\n";
        exit(1);
        break;

    case E_USER_WARNING:
        echo "<b>My WARNING</b> [$errno] $errstr<br />\n";
        break;

    case E_USER_NOTICE:
        echo "<b>My NOTICE</b> [$errno] $errstr<br />\n";
        break;

    default:
        echo "Unknown error type: [$errno] $errstr<br />\n";
        break;
    }

    /* Don't execute PHP internal error handler */
    return true;
}

// set to the user defined error handler
$old_error_handler = set_error_handler("myErrorHandler");

Answer 2

I would use Try/catch along with file_put_contents to save the data. For example:

try {
    function_que_pode_dar_erro();
} catch (Exception $e) {
    file_put_contents('logfile.log', 'Caught exception: ',  $e->getMessage(), PHP_EOL . print_r($_POST, true).PHP_EOL, FILE_APPEND);
    exit; // pode dar exit para não continuar a execução ou fazer outra coisa
}