Lemmy User Comment Scraper

index.php

<?php
function fetchContent($url) {
    $production = false; //Change as needed
    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    if (empty($production)) {
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
    }
    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
    curl_setopt($ch, CURLOPT_MAXREDIRS, 10);
    curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36');
    $content = curl_exec($ch);
    if (curl_errno($ch)) {
        die('Curl error: ' . curl_error($ch));
    }
    curl_close($ch);
    return $content;
}

$instance = isset($_POST['instance']) ? $_POST['instance'] : (isset($_GET['instance']) ? $_GET['instance'] : null);
$username = isset($_POST['username']) ? $_POST['username'] : (isset($_GET['username']) ? $_GET['username'] : null);

if (!$instance || !$username) {
    die(json_encode(['error' => 'Both "instance" and "username" parameters are required.']));
}

//Sanitize the user input
$instance = filter_var($instance, FILTER_SANITIZE_URL);
$username = preg_replace("/[^a-zA-Z0-9_\-]/", '', $username);

if (!$instance || !$username) {
    die(json_encode(['error' => 'Invalid "instance" or "username" provided.']));
}

$url = "$instance/api/v3/user/?username=$username&limit=50";

//Initial fetch to get the comment_count
$content = fetchContent($url);
$data = json_decode($content, true);
$all_comments = [];
$total_pages = ceil($data['person_view']['counts']['comment_count'] / 50);
$date = date("m-d-Y_H-i-s");

//Fetch all comments
for ($i = 1; $i <= $total_pages; $i++) {
    $page_url = "$url&page=$i";
    $page_content = fetchContent($page_url);
    $page_data = json_decode($page_content, true);
    
    $all_comments = array_merge($all_comments, $page_data['comments']);
}

//Replace the 'comments' section in the last page_data with our merged comments
$page_data['comments'] = $all_comments;

//Append additional data
$page_data['website'] = $instance;
$page_data['username'] = $username;
$page_data['date'] = $date;

$filename = str_replace(["https://", "https://www."], "", $instance) . "-$username-" . $date . ".json";
header('Content-Disposition: attachment; filename=' . $filename);
header('Content-Type: application/json');
echo json_encode($page_data);