func.php

<?php
function checkUser($username) {
    $url = "https://api.scratch.mit.edu/users/$username";
    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_HEADER, true);

    $response = curl_exec($ch);
    $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    curl_close($ch);

    // 404の場合はfalse、それ以外はtrue
    if ($http_code == 404) {
        return false;
    } else {
        return true;
    }
}

function getScratchProjectComments($authorName, $projectId, $limit, $offset) {
    $cacheBust = rand(0, 9999);
    $url = "https://api.scratch.mit.edu/users/{$authorName}/projects/{$projectId}/comments/?limit={$limit}&offset={$offset}&cachebust={$cacheBust}";
    
    $response = file_get_contents($url);
    $comments = json_decode($response, true);

    if (!is_array($comments)) {
        return [];
    }

    foreach ($comments as &$comment) {
        $comment["source"] = "project";
        $comment["source_id"] = $projectId;
    }

    return parseObjectList($comments);
}

function parseObjectList($comments) {

    return $comments;
}