PHP 单文件短链服务：SQLite 存储，零依赖，支持自定义短码 [复制链接]

短链服务是站长工具里很常用的功能。这里给出一个 PHP + SQLite 的单文件实现，不依赖任何第三方扩展（SQLite3 通常在 PHP 里默认启用），支持自动生成短码和自定义短码，做完直接能用。

完整代码（shorturl.php）

<?php
declare(strict_types=1);

$dbFile = __DIR__ . '/shorturl.db';
$baseUrl = 'https://你的域名/';
$pdo = new PDO('sqlite:' . $dbFile);
$pdo->exec('CREATE TABLE IF NOT EXISTS links (
    code TEXT PRIMARY KEY,
    url TEXT NOT NULL,
    created_at INTEGER NOT NULL
)');

// 路由判断
$path = parse_url($_SERVER['REQUEST_URI'], PHP_URL_PATH);
$path = trim($path, '/');

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    // 生成短链: POST { "url": "https://...", "code": "可选" }
    $input = json_decode(file_get_contents('php://input'), true);
    $url = filter_var($input['url'] ?? '', FILTER_VALIDATE_URL);
    if (!$url) { json(['code' => 1, 'message' => 'url 无效'], 400); }

    $code = isset($input['code']) ? preg_replace('/[^a-zA-Z0-9_-]/', '', $input['code']) : '';
    if ($code === '') {
        $code = base62(bin2hex(random_bytes(6)));
    }
    $stmt = $pdo->prepare('SELECT 1 FROM links WHERE code = ?');
    $stmt->execute([$code]);
    if ($stmt->fetchColumn()) { json(['code' => 2, 'message' => '短码已存在'], 409); }

    $pdo->prepare('INSERT INTO links (code, url, created_at) VALUES (?, ?, ?)')
         ->execute([$code, $url, time()]);
    json(['code' => 0, 'short' => $baseUrl . $code]);
}

if ($path !== '') {
    // 跳转: 访问短码
    $stmt = $pdo->prepare('SELECT url FROM links WHERE code = ?');
    $stmt->execute([$path]);
    $url = $stmt->fetchColumn();
    if ($url) {
        header('Location: ' . $url, true, 302);
        exit;
    }
    http_response_code(404);
    echo '短链不存在';
    exit;
}

json(['code' => 0, 'message' => '短链服务运行中', 'usage' => 'POST {url, code?} => 生成，GET /code => 跳转']);

function base62(string $hex): string {
    $chars = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    $num = hexdec($hex);
    if ($num === 0) return '0';
    $out = '';
    while ($num > 0) {
        $out = $chars[$num % 62] . $out;
        $num = intdiv($num, 62);
    }
    return $out;
}

function json(array $data, int $status = 200): never {
    http_response_code($status);
    header('Content-Type: application/json; charset=utf-8');
    echo json_encode($data, JSON_UNESCAPED_UNICODE);
    exit;
}

使用说明

文件放任意 PHP 站点目录即可运行。生成短链用 POST 传 JSON，自动生成短码约 8~11 位；想用自己的短码传 code 字段。访问 https://域名/短码 即 302 跳转。SQLite 数据自动落库到同级 shorturl.db，备份时拷走这个文件即可。