compress.php

<?php

  function compress($source, $type) {
    global $lastError;
    global $yuiPath;
    
		$cmd = sprintf('java -jar %s --type %s --charset UTF-8 --line-break 1000', escapeshellarg($yuiPath), $type);
		$process = proc_open(
			$cmd,
			array(
				0 => array("pipe", "r"),
				1 => array("pipe", "w"),
				2 => array("pipe", "w"),
			),
			$pipes
		);

		fwrite($pipes[0], $source);
		fclose($pipes[0]);

		$output = array (
			"stdout" => "",
			"stderr" => "",
		);

		$readSockets = array (
			"stdout" => $pipes[1],
			"stderr" => $pipes[2]
		);
		$empty = array ();
		while (false !== stream_select($readSockets, $empty, $empty, 1))
		{
			$eof = true;
			foreach ($readSockets as $key => $stream)
			{
				$output[$key] = stream_get_contents($stream);
				$meta = stream_get_meta_data($stream);
				$eof = $eof && true === $meta['eof'];
			}
			if ($eof)
			{
				break;
			}

			$readSockets = array (
				"stdout" => $pipes[1],
				"stderr" => $pipes[2]
			);
		}

		$compressed = $output['stdout'];
		$errors = $output['stderr'];
		$lastError = "" !== $errors;

		if ($lastError)
		{
			$compressed = "";
			$lastError = sprintf(
				"alert('compression errors, check your source and console for details'); console.error(%s); ",
				json_encode($errors)
			);
		}

		proc_close($process);
		return $compressed;
	}