discogs.php

<?php

ini_set('user_agent', 'ThybziDiscogsClient/1.1 +http://thybzi.com/wishlist');
define('BASE_URI', 'https://api.discogs.com/');
define('API_TOKEN', 'YOUR_TOKEN_HERE'); // get one on https://www.discogs.com/settings/developers
define('CACHE_DIR', __DIR__ . '/../cache/');
define('CACHE_LIFE', 24 * 60 * 60);
define('PER_PAGE', 100);

function getUriContent($uri) {
    $context = stream_context_create([
        'http' => [
            'method' => 'GET',
            'header' => 'Authorization: Discogs token=' . API_TOKEN . "\r\n",
        ]
    ]);
    if (strpos($uri, 'http') !== 0) {
        $uri = BASE_URI . $uri;
    }
    return file_get_contents($uri, false, $context);
}

function getPaginatedUriContent($uri) {
    $data = [];
    $next_page_uri = $uri . '?' . http_build_query(['per_page' => PER_PAGE]);
    while (!is_null($next_page_uri)) {
        $content = getUriContent($next_page_uri);
        $data = array_merge_recursive($data, json_decode($content, true));
        if (isset($data['pagination'])) {
            $next_page_uri = isset($data['pagination']['urls']['next']) ?
                $data['pagination']['urls']['next'] :
                null;
            unset($data['pagination']);
        } else {
            $next_page_uri = null;
        }
    }
    return json_encode($data);
}

function getCacheFilePath($cmd, $id) {
    return CACHE_DIR . $cmd . (is_null($id) ? '' : "_$id") . '.json';
}

function getCommand($cmd, $id) {
    $cachefile_path = getCacheFilePath($cmd, $id);
    if (file_exists($cachefile_path) && filemtime($cachefile_path) >= (time() - CACHE_LIFE)) {
        return file_get_contents($cachefile_path);
    }

    switch ($cmd) {
        case 'wantlist':
            $content = getPaginatedUriContent('users/thybzi/wants');
            break;
        case 'collection':
            $content = getPaginatedUriContent('users/thybzi/collection/folders/0/releases');
            break;
        case 'master':
            $content = getUriContent('masters/' . $id);
            break;
    }

    file_put_contents($cachefile_path, $content);
    return $content;
}


$cmd = isset($_GET['cmd']) ? $_GET['cmd'] : 'wantlist';
if (in_array($cmd, ['wantlist', 'collection', 'master'])) {
    $id = isset($_GET['id']) ? $_GET['id'] : NULL;
    header('Access-Control-Allow-Origin: *');
    header('Content-Type: application/json');
    echo getCommand($cmd, $id);
} else {
    die('Unknown command: ' . $cmd);
}