Error using PHP Simple HTML DOM Parser in Symfony - php

Question

Here is a basic example of how simple_html_dom works in a standalone php file.
test.php:
include ('simple_html_dom.php');
$url = "http://www.google.com";
$html = new simple_html_dom();
$html->load_file($url);
print $html;
If I execute it with the command: php test.php
It dumps correctly the html of the website (in this example, google.com)
Now let's take a look at a basic example of code using a Symfony task:
class parserBasic extends sfBaseTask {
public function configure()
{
$this->namespace = 'parser';
$this->name = 'basic';
}
public function execute($arguments = array(), $options = array())
{
$url = "http://www.google.com";
$html = new simple_html_dom();
$html->load_file($url);
print $html;
}
}
This file it's located under: <appname>/lib/task
I don't need to include the library in the file because being under the lib/task folder, it gets automatically loaded.
I execute the task using this command: php symfony parser:basic
And I get the following error message:
PHP Fatal error:
Call to a member function innertext() on a non-object in
/home/<username>/<appname>/lib/task/simple_html_dom.php on line 1688
Any suggestions?

Answer 1

The problem comes from Symfony.
In fact, if an error occur when loading the file with simple_html_dom, it won't say anything but returning false.
For example, if you perform this in your task:
$url = "http://www.google.com";
$html = new simple_html_dom();
$res = $html->load_file($url);
if (false === $res)
{
throw new Exception("load_file failed.");
}
print $html;
You will get an exception. If you tweak simple_html_dom to display en error when loading a file, around line 1085:
// load html from file
function load_file()
{
$args = func_get_args();
$this->load(call_user_func_array('file_get_contents', $args), true);
// Throw an error if we can't properly load the dom.
if (($error=error_get_last())!==null) {
// I added this line to see any errors
var_dump($error);
$this->clear();
return false;
}
}
You will see:
array(4) {
["type"]=>
int(8)
["message"]=>
string(79) "ob_end_flush(): failed to delete and flush buffer. No buffer to delete or flush"
["file"]=>
string(62) "/home/.../symfony.1.4/lib/command/sfCommandApplication.class.php"
["line"]=>
int(541)
}
I usually got this error (which is, in fact, a notice) when using task. The problem is here, in sfCommandApplication, with ob_end_flush:
/**
* Fixes php behavior if using cgi php.
*
* #see http://www.sitepoint.com/article/php-command-line-1/3
*/
protected function fixCgi()
{
// handle output buffering
#ob_end_flush();
ob_implicit_flush(true);
To fix that, I comment the line with #ob_end_flush();. And every thing goes fine. I know, it's an ugly fix, but it works. An other way to fix that, is to disable notice from PHP (in php.ini), like :
// Report all errors except E_NOTICE
error_reporting = E_ALL ^ E_NOTICE