Github Push Webhook - https://lejenome.tik.tn/post/github-push-webhook-implementation

github_webhook.php

<?php
// Webhook code to update repo clone and execute required deployement code when new commit was pushed
// Webhook content-type should be set to application/json and a random secret code should be set too.

// Secret Random Code You set on github webhook settings
const SECRET_TOKEN = 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX';

if(strcasecmp($_SERVER['REQUEST_METHOD'], 'POST') != 0){
        throw new Exception('Request method must be POST!');
}
if (! in_array($_SERVER['HTTP_X_GITHUB_EVENT'], ['push', 'ping'])) {
    throw new Exception('Request event should be either "push" or "ping"!');
}

$contentType = isset($_SERVER["CONTENT_TYPE"]) ? trim($_SERVER["CONTENT_TYPE"]) : '';
if(strcasecmp($contentType, 'application/json') != 0){
        throw new Exception('Content type must be: application/json');
}

$hash =  hash_hmac('sha1', file_get_contents('php://input'), SECRET_TOKEN, false);

if ($_SERVER['HTTP_X_HUB_SIGNATURE'] == 'sha1=' . $hash) {
    $json = json_decode(file_get_contents('php://input'), true);
    if(!is_array($json)){
            throw new Exception('Received content contained invalid JSON!');
    }
    $commands = array();
    if ($json['repository']['full_name'] == 'USERNAME/REPO1-DJANGO-APP') {
        $commands = array(
            'whoami',
            'cd /PATH/TO/SITE1 && git pull',
            'cd /PATH/TO/SITE1 && git status',
            // 'cd /PATH/TO/SITE && git submodule sync',
            // 'cd /PATH/TO/SITE1 && git submodule update',
            // 'cd /PATH/TO/SITE1 && git submodule status',
            'cd /PATH/TO/SITE1 && bash -c "source env/bin/activate && pip3 install -r requirements.txt"',
            'cd /PATH/TO/SITE1 && bash -c "source env/bin/activate && python3 manage.py migrate --noinput"',
            'cd /PATH/TO/SITE1 && bash -c "source env/bin/activate && python3 manage.py collectstatic --clear --link --noinput"',
            'kill -HUP $(pidof uwsgi) && echo "Server reloaded" || echo "Can not reload the server"',
        );
    } else if ($json['repository']['full_name'] == 'USERNAME/REPO2-STATIC-WEBSITE') {
        $commands = array(
            'whoami',
            'cd /PATH/TO/SITE2 && git pull',
            'cd /PATH/TO/SITE2 && git status',
        );
    } else {
        throw new Exception('Repo is not in the list');
    }
    // Run the commands for output
    foreach($commands AS $command){
        // Run it
        try {
            $tmp = shell_exec($command);
        } catch (Exception $e) {
            $tmp = "ERROR!\n";
            $tmp = 'Caught exception: '.  $e->getMessage(). "\n";
        }
        // Output
        echo "sh> $command\n";
        echo htmlentities(trim($tmp)) . "\n";
    }
} else {
    throw new Exception('Wrong signature hash!');
}
?>

Blog post: https://lejenome.tik.tn/post/github-push-webhook-implementation