如何使用PHP进行JWT鉴权和认证？

composer require firebase/php-jwt lcobucci/jwt

<?php

use FirebaseJWTJWT;
use LcobucciJWTBuilder;
use LcobucciJWTSignerHmacSha256;

// 用户登录成功后，生成JWT
function generateJWT($userId, $secretKey) {
    $time = time();
    $token = (new Builder())
        ->issuedBy('example.com') // 发行者
        ->permittedFor('example.com') // 接受者
        ->identifiedBy('1', true) // 标识符
        ->issuedAt($time) // 发行时间
        ->expiresAt($time + 3600) // 过期时间
        ->withClaim('userId', $userId) // 自定义声明
        ->getToken(new Sha256(), new Key($secretKey));

    return $token;
}

$jwt = generateJWT(1, 'your-secret-key');
echo $jwt;

<?php

use FirebaseJWTJWT;

// 验证并解析JWT
function verifyJWT($jwt, $secretKey) {
    try {
        $decoded = JWT::decode($jwt, $secretKey, ['HS256']);
        return $decoded;
    } catch (Exception $e) {
        return null;
    }
}

$jwt = $_SERVER['HTTP_AUTHORIZATION'];
$decoded = verifyJWT($jwt, 'your-secret-key');

if ($decoded) {
    $userId = $decoded->userId;
    echo "用户ID：$userId";
} else {
    echo "无效的JWT";
}

<?php

use FirebaseJWTJWT;
use LcobucciJWTBuilder;
use LcobucciJWTSignerHmacSha256;

// 刷新JWT
function refreshJWT($jwt, $secretKey) {
    $current = time();
    $decoded = JWT::decode($jwt, $secretKey, ['HS256']);
    
    if ($decoded->exp - $current > 1800) { // 如果剩余有效期超过30分钟，则不刷新JWT
        return $jwt;
    }
    
    $newToken = (new Builder())
        ->issuedBy($decoded->iss)
        ->permittedFor($decoded->aud)
        ->identifiedBy($decoded->jti, true)
        ->issuedAt($current)
        ->expiresAt($current + 3600)
        ->withClaim('userId', $decoded->userId)
        ->getToken(new Sha256(), new Key($secretKey));
        
    return $newToken;
}

$jwt = $_SERVER['HTTP_AUTHORIZATION'];
$refreshedJWT = refreshJWT($jwt, 'your-secret-key');

echo $refreshedJWT;