in php how do I use preg replace to turn a url into a tinyurl

Question

I need to convert a string of text containing a long url into the same string but with a tinyurl (using the tinyurl api). eg. convert "blah blah blah /http://example.com/news/sport blah blah blah" into "blah blah blah http://tinyurl.com/yaeocnv blah blah blah".

How can it be done? PLEASE NOTE I added a slash before the long url as I'm only allowed to post one link

Answer 1

In order to shorten an arbitrary number of URLs in your text, put the API stuff in a function which takes the long URL and returns the short URL. Then apply this function via PHP's preg_replace_callback function to your text. This would look something like this:

<?php

function shorten_url($matches) {
    // EDIT: the preg function will supply an array with all submatches
    $long_url = $matches[0];

    // API stuff here...
    $url = "http://tinyurl.com/api-create.php?url=$long_url";
    return file_get_contents($url);
}

$text = 'I have a link to http://www.example.com in this string';

$textWithShortURLs = preg_replace_callback('|http://([a-z0-9?./=%#]{1,500})|i', 'shorten_url', $text);
echo $textWithShortURLs;

?>

Don't count on that pattern too much, just wrote it on-the-fly without any testing, maybe someone else can help. See http://php.net/preg-replace-callback

Answer 2

To answer your question of how to do this with preg_replace, you can use the e modifyer.

function tinyurlify($href) {
 return file_get_contents("http://tinyurl.com/api-create.php?url=$href");
}
$str = preg_replace('/(http:\/\/[^\s]+)/ie', "tinyurlify('$1')", $str);