Check if links are broken in php

Question

I wonder if there is any good PHP script (libraries) to check if link are broken? I have links to documents in a mysql table and could possibly just check if the link leads to a the document, or if I am redirected to anther url. Any idea? I would prefer to do it in PHP.

Might be related to: Check link works and if not visually identify it as broken

Answer 1

You can check for broken link using this function:

function check_url($url) {

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_HEADER, 1);
    curl_setopt($ch , CURLOPT_RETURNTRANSFER, 1);
    $data = curl_exec($ch);
    $headers = curl_getinfo($ch);
    curl_close($ch);

    return $headers['http_code'];
}

You need to have CURL installed for this to work. Now you can check for broken links using:

$check_url_status = check_url($url);
if ($check_url_status == '200')
   echo "Link Works";
else
   echo "Broken Link";

Also check this link for HTTP status codes : HTTP Status Codes

I think you can also check for 301 and 302 status codes.

Also another method would be to use get_headers function . But this works only if your PHP version is greater than 5 :

function check_url($url) {
   $headers = @get_headers( $url);
   $headers = (is_array($headers)) ? implode( "\n ", $headers) : $headers;

   return (bool)preg_match('#^HTTP/.*\s+[(200|301|302)]+\s#i', $headers);
}

In this case just check the output :

if (check_url($url))
   echo "Link Works";
else
   echo "Broken Link";

Hope this helps you :).

Answer 2

You can do this in few ways:

First way - curl

function url_exists($url) {
    $ch = @curl_init($url);
    @curl_setopt($ch, CURLOPT_HEADER, TRUE);
    @curl_setopt($ch, CURLOPT_NOBODY, TRUE);
    @curl_setopt($ch, CURLOPT_FOLLOWLOCATION, FALSE);
    @curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
    $status = array();
    preg_match('/HTTP\/.* ([0-9]+) .*/', @curl_exec($ch) , $status);
    return ($status[1] == 200);
}

Second way - if you dont have curl installed - get headers

function url_exists($url) {
    $h = get_headers($url);
    $status = array();
    preg_match('/HTTP\/.* ([0-9]+) .*/', $h[0] , $status);
    return ($status[1] == 200);
}

Third way - fopen

function url_exists($url){
    $open = @fopen($url,'r');
    if($handle !== false){
       return true;
    }else{
       return false;
    }
}

First & second solutions