git webhook pull code

update_code.php

<?php
function exitJson($err, $msg , $result='')
{
	echo json_encode(array('err'=>$err, 'msg'=>$msg , 'result'=>$result));
	exit();
}
$postdata = file_get_contents("php://input");
$jsondata = json_decode($postdata);
if($jsondata->ref == 'refs/heads/master'){ // only deploy on master branch
	$return_val;
	$output = array();
	$ok_str = 'ok';
    $current_directory = dirname(__FILE__);
	if(strpos($jsondata->compare, basename($current_directory))>0){
		$cmd = 'cd ' . $current_directory . ' && git pull origin master';
	}
	else{
		$cmd = 'git pull origin master';
	}
	$cmd .= ' 2>&1';
	exec($cmd, $output, $return_val);
	if($return_val != 0){
		// record error log
		$err_msg = join("\n", $output);
		exitJson(1, $output);
	}
	else{
		exitJson(0, $ok_str);
	}
}
else{
	exitJson(1,'invalid request');
}
?>