How to loop the result from findnodes() with HTML::TreeBuilder::XPath - perl

Question

I have my script to monitor some Facebook pages. Since Facebook API banned page public access permission on 4-SEP-2019. I need to parse the content by xpath method.
Each Facebook post is wrap by div[contains(#class,"userContentWrapper")]. I would like to loop posts one by one to find a desired data.
I don't known why $message = $post->findvalue('//div[#data-testid="post_message"]//p'); show all text in <p> of every posts.
use LWP::UserAgent;
$ua = new LWP::UserAgent;
$request = new HTTP::Request;
$request->url('https://www.facebook.com/pg/FIFA/posts/');
$request->method('GET');
$request->header('User-Agent' => 'Mozilla/5.0 Chrome/71.0.3578.98 Safari/537.36');
$response = $ua->request($request);
open(HTM, ">zzz.htm");
print HTM $response->content;
close(HTM);
use HTML::TreeBuilder::XPath;
$tree = HTML::TreeBuilder::XPath->new_from_content($response->content);
$posts = $tree->findnodes('//div[contains(#class,"userContentWrapper")]');
for my $post (#{$posts})
{
$id = $post->findnodes('//div[#data-testid="story-subtitle"]/#id');
$id = $id->[0]->getValue;
print "id = $id\n\n";
$object_id = $post->findnodes('//div[#data-testid="story-subtitle"]//a/#href');
$object_id = 'https://www.facebook.com' . $object_id->[0]->getValue;
print "object_id = $object_id\n\n";
$message = $post->findvalue('//div[#data-testid="post_message"]//p');
# $message = $message->[0]->getValue;
print "$message\n\n";
$ajaxify = $post->findnodes('//div[#class="mtm"]//a/#ajaxify');
$ajaxify = $ajaxify->[0]->getValue;
print "ajaxify = $ajaxify\n\n";
$ploi = $post->findnodes('//div[#class="mtm"]//a/#data-ploi');
$ploi = $ploi->[0]->getValue;
print "ploi = $ploi\n\n";
# $plsi = $post->findnodes('//div[#class="mtm"]//a/#data-plsi');
# $plsi = $plsi->[0]->getValue;
# print "plsi = $plsi\n\n";
$href = $post->findnodes('//div[#class="mtm"]//a/#href');
$href = 'https://www.facebook.com' . $href->[0]->getValue;
print "href = $href\n\n";
print "---------------------------------------------------------\n\n";
}

Answer 1

The post is unclear and it seems to contain multiple questions. This needs to be fixed, but in the mean time, I'll address the following:
I would like to loop posts one by one to find a desired data.
From HTML::TreeBuilder::XPath,
findnodes ($path)
Returns a list of nodes found by $path. In scalar context returns an Tree::XPathEngine::NodeSet object.
From Tree::XPathEngine::NodeSet,
get_nodelist()
Returns a list of nodes. See Tree::XPathEngine::XMLParser for the format of the nodes.
So,
my #posts = $tree->findnodes('...');
for my $post (#posts) { ... }
or
my $posts = $tree->findnodes('...');
for my $post ($posts->get_nodelist()) { ... }
Any other questions should be posted as separate Questions.