PHP Parser - Find String in HTML - php

Question

I want to find a string on another website. I have been looking at parsers and I do not know the best way to do it. I looked at an HTML DOM parser but I need just a simple one line output. I just want to get the link "url: 'http://s2.example.com/streams/i23374.mp4?k=12f34588cf171f3bbf3d35da4db43b06'" to a variable.
<script>
flowplayer("player", "http://www.example.com/flowplayer-3.2.16.swf", {
canvas: {
backgroundGradient: "none",
backgroundColor: "#000000"
},
clip: {
provider: 'lighttpd',
url: 'http://s1.example.com/streams/i23374.mp4?k=12f34588cf171f3bbf3d35da4db43b06',
scaling: 'fit'
},
plugins: {
lighttpd: {
url: 'http://www.example.com/flowplayer.pseudostreaming-3.2.12.swf'
}
}
});
</script>

Answer 1

Here's a handy function for grabbing the text from between two delimiters;
<?php
function extract_unit($string, $start, $end)
{
$pos = stripos($string, $start);
$str = substr($string, $pos);
$str_two = substr($str, strlen($start));
$second_pos = stripos($str_two, $end);
$str_three = substr($str_two, 0, $second_pos);
$unit = trim($str_three); // remove whitespaces
return $unit;
}
echo extract_unit($webpageSource, 'flowplayer("player", "', '", {');
?>

Answer 2

I would use DOMDocument:
For getting a link off of an anchor, it's:
$dd = new DOMDocument;
#$dd->loadHTMLFile('http://s2.example.com/streams/i23374.mp4?k=12f34588cf171f3bbf3d35da4db43b06');
if($a = $dd->getElementsByTagName('a')){
foreach($a as $t){
$links[] = $t->getAttribute('href');
}
}
Now $links is an Array with each href, or if(!isset($links)) there are no results.
To get JSON from a script tag:
$dd = new DOMDocument;
#$dd->loadHTMLFile('http://s2.example.com/streams/i23374.mp4?k=12f34588cf171f3bbf3d35da4db43b06');
if($s = $dd->getElementsByTagName('script')){
$c = $dd->sameHTML($s->item(0)));
}
Change item(0) to the level where the script tag is on their page. Now $c is a String. So:
preg_match_all("/url: '.+'/", $c, $results);
$results is an Array should contain url: 'whatever'.
So:
foreach($results as $v){
$a[] = preg_replace('/url: /', '', $v);
}
$a is Array of results.

Answer 3

Mostly RegExp is the best way to parse string, although it's not recommended to handle JSON.
Here's an example(I encoded the string, it's the same as your raw HTML):
<?php
$data = base64_decode("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");
if(preg_match('/clip:\s*\{[\s\S]+url:\s*\'(\S+)\',\s*scaling/', $data, $match) === 1)
echo $match[1];
?>
Although it's encoded in JSON, it can't be parsed by PHP's json_decode because PHP's JSON format is too strict (attributes should be wrapped in quotes).