Post to facebook page from php

Facebook has very weird documentation. If you have facebook page and want to post on page with php script here what you need:

1. Facebook page
2. Your user never ending access token. Here normal guide how to get it https://medium.com/@Jenananthan/how-to-create-non-expiry-facebook-page-token-6505c642d0b1
3. Get your pageId. Go to your page Information (or About)->In the very bottom your pageId. At the moment of the article it is here https://www.facebook.com/pg/<pageUrl>/about/. Where <pageUrl> is your facebook page slug.
4. Get facebook php sdk  https://github.com/facebook/php-graph-sdk with composer

composer require facebook/graph-sdk

Note: this command is good at the moment of this article. But you better go to github and copy, because they can change it.

Now here the script

$appId = ''; //your App Id
$appSecret = ''; //your app secret
$pageId = '0000000000'; //id of the page you want to publish on
$userAccessToken = ''; //Your never expire user access token

$fb = new \Facebook\Facebook([
    'app_id' => $appId,
    'app_secret' => $appSecret,
    'default_graph_version' => 'v3.0',
]);
$linkData = [
    'link' => 'http://google.com', //TODO  change
    'message' => "My message", //TODO  change
];


$longLivedToken = $fb->getOAuth2Client()->getLongLivedAccessToken($userAccessToken);
$fb->setDefaultAccessToken($longLivedToken);
$response = $fb->sendRequest('GET', $pageId, ['fields' => 'access_token'])
    ->getDecodedBody();

$foreverPageAccessToken = $response['access_token'];
$fb->setDefaultAccessToken($foreverPageAccessToken);
$response = $fb->post("/$pageId/feed", $linkData);

Note: If you're using github then values for first 4 variables should be outside of git. For example in env file or php file which is in gitignore.

php get substring after character or word

Here we will get substring after word '/'

$item = 'posts/p10504';

substr(strrchr($item, '/'),1);
substr($item , strpos($item , '/') + 1);

//both lines has value of p10504