Solution for "Fatal error: Maximum function nesting level of '100' reached, aborting!" in PHP

I have made a function that finds all the URLs within an html file and repeats the same process for each html content linked to the discovered URLs. The function is recursive and can go on endlessly. However, I have put a limit on the recursion by setting a global variable which causes the recursion to stop after 100 recursions.

However, php returns this error:

Fatal error: Maximum function nesting level of '100' reached, aborting! in D:\wamp\www\crawler1\simplehtmldom_1_5\simple_html_dom.php on line 1355

I found a solution here: Increasing nesting function calls limit but this is not working in my case.

I am quoting one of the answers from the link mentioned above. Please do consider it.

"Do you have Zend, IonCube, or xDebug installed? If so, that is probably where you are getting this error from.

I ran into this a few years ago, and it ended up being Zend putting that limit there, not PHP. Of course removing it will let >you go past the 100 iterations, but you will eventually hit the memory limits."

Is there a way to increase the maximum function nesting level in PHP

Solution 1:

Increase the value of xdebug.max_nesting_level in your php.ini

Solution 2:

A simple solution solved my problem. I just commented this line:

zend_extension = "d:/wamp/bin/php/php5.3.8/zend_ext/php_xdebug-2.1.2-5.3-vc9.dll

in my php.ini file. This extension was limiting the stack to 100 so I disabled it. The recursive function is now working as anticipated.

Solution 3:

Rather than going for a recursive function calls, work with a queue model to flatten the structure.

$queue = array('http://example.com/first/url');
while (count($queue)) {
    $url = array_shift($queue);

    $queue = array_merge($queue, find_urls($url));
}

function find_urls($url)
{
    $urls = array();

    // Some logic filling the variable

    return $urls;
}

There are different ways to handle it. You can keep track of more information if you need some insight about the origin or paths traversed. There are also distributed queues that can work off a similar model.

Solution 4:

Another solution is to add xdebug.max_nesting_level = 200 in your php.ini

Solution 5:

Rather than disabling the xdebug, you can set the higher limit like

xdebug.max_nesting_level=500