苹果授权登录(Sign in with Apple)-JAVA后端开发

1、 业务逻辑分析

IOS授权登录流程与微信授权登录大同小异，唯一区别的在于需要调用苹果api获取公钥，接口地址为：https://appleid.apple.com/auth/keys。
首先是IOS APP端拿到identifyToken交给后端，后端拿到identifyToken后，首先调用IOS的公钥API拿到IOS的公钥，这里会获取到两个公钥，然后使用公钥对identifyToken进行校验，校验通过后，对identityToken进行解码，解码后可以到授权的唯一标识sub,之后做业务侧的注册登录逻辑。
这里有一个坑，就是在校验identifyToken的时候，偶尔会校验不通过，原因是我们通过IOS的公钥API会拿到两个密钥，如果只拿其中一个去做校验，就会出现这种情况，所以当第一个密钥校验不通过的时候，再拿第二个密钥再做一次校验。

大致流程如下图：

代码实现

需要添加的依赖：

        <dependency>
            <groupId>io.jsonwebtokengroupId>
            <artifactId>jjwtartifactId>
            <version>0.9.1version>
        dependency>
        <dependency>
            <groupId>com.auth0groupId>
            <artifactId>jwks-rsaartifactId>
            <version>0.9.0version>
        dependency>

工具类实现

public class AppleUitl {
     

    private static final Logger logger = LoggerFactory.getLogger(AppleUitl.class);

    /**
     * 获取苹果的公钥
     * @return
     * @throws Exception
     */
    private static JSONArray getAuthKeys() throws Exception {
     
        String url = "https://appleid.apple.com/auth/keys";
        RestTemplate restTemplate = new RestTemplate();
        JSONObject json = restTemplate.getForObject(url,JSONObject.class);
        JSONArray arr = json.getJSONArray("keys");
        return arr;
    }

    public static Boolean verify(String jwt) throws  Exception{
     
        JSONArray arr = getAuthKeys();
        if(arr == null){
     
            return false;
        }
        JSONObject authKey = null;

        //先取苹果第一个key进行校验
        authKey = JSONObject.parseObject(arr.getString(0));
        if(verifyExc(jwt, authKey)){
     
            return true;
        }else{
     
            //再取第二个key校验
            authKey = JSONObject.parseObject(arr.getString(1));
            return verifyExc(jwt, authKey);
        }

    }

    /**
     * 对前端传来的identityToken进行验证
     * @param jwt 对应前端传来的 identityToken
     * @param authKey 苹果的公钥 authKey
     * @return
     * @throws Exception
     */
    public static Boolean verifyExc(String jwt, JSONObject authKey) throws Exception {
     

        Jwk jwa = Jwk.fromValues(authKey);
        PublicKey publicKey = jwa.getPublicKey();

        String aud = "";
        String sub = "";
        if (jwt.split("\\.").length > 1) {
     
            String claim = new String(Base64.decodeBase64(jwt.split("\\.")[1]));
            aud = JSONObject.parseObject(claim).get("aud").toString();
            sub = JSONObject.parseObject(claim).get("sub").toString();
        }
        JwtParser jwtParser = Jwts.parser().setSigningKey(publicKey);
        jwtParser.requireIssuer("https://appleid.apple.com");
        jwtParser.requireAudience(aud);
        jwtParser.requireSubject(sub);

        try {
     
            Jws<Claims> claim = jwtParser.parseClaimsJws(jwt);
            if (claim != null && claim.getBody().containsKey("auth_time")) {
     
                System.out.println(claim);
                return true;
            }
            return false;
        } catch (ExpiredJwtException e) {
     
            logger.error("apple identityToken expired", e);
            return false;
        } catch (Exception e) {
     
            logger.error("apple identityToken illegal", e);
            return false;
        }
    }



    /**
     * 对前端传来的JWT字符串identityToken的第二部分进行解码
     * 主要获取其中的aud和sub，aud大概对应ios前端的包名，sub大概对应当前用户的授权的openID
     * @param identityToken
     * @return  {"aud":"com.xkj.****","sub":"000***.8da764d3f9e34d2183e8da08a1057***.0***","c_hash":"UsKAuEoI-****","email_verified":"true","auth_time":1574673481,"iss":"https://appleid.apple.com","exp":1574674081,"iat":1574673481,"email":"****@qq.com"}
     */
    public static JSONObject parserIdentityToken(String identityToken){
     
        String[] arr = identityToken.split("\\.");
        Base64 base64 = new Base64();
        String decode = new String (base64.decodeBase64(arr[1]));
        String substring = decode.substring(0, decode.indexOf("}")+1);
        JSONObject jsonObject = JSON.parseObject(substring);
        return  jsonObject;
    }

}

业务侧注册登录,具体的注册登录逻辑这里不再详细介绍

 /**
     * iOS appleid 授权登录
     * @param identityToken
     * @param request
     * @return
     */
    @Transactional
    public ApiResult appleLogin(String identityToken,HttpServletRequest request){
     
        try {
     
            Map<String, String> map = new HashMap<String, String>();
            //验证identityToken
            if(!AppleUitl.verify(identityToken)){
     
                return new ApiResult(ApiCode.VALIDATION_ERROR, "授权验证失败");
            }
            //对identityToken解码
            JSONObject json = AppleUitl.parserIdentityToken(identityToken);
            if(json == null){
     
                return new ApiResult(ApiCode.VALIDATION_ERROR, "授权解码失败");
            }
            String ip = Servlets.getRemoteAddr(request);
            User user = oauthAppleService.apple_login(json, ip);
            //将用户信息存到redis并返回token, token有效期为31天
            String token = tokenRedisService.put(user);
            map.put("token",token);
            return new ApiResult(ApiCode.SUCCESS, "success", map);
        }catch (Exception e){
     
            logger.error("app wxLogin error:" + e.getMessage(),e);
            return new ApiResult(ApiCode.SYS_EXCEPTION, "系统错误");
        }

    }