利用MYSQL的函数实现用户登录功能，进出都是JSON(第二版)

利用MYSQL的函数实现用户登录功能，进出都是JSON(第二版)

CREATE DEFINER=`root`@`%` FUNCTION `uc_session_login`(
    `reqjson` JSON,
    `srvjson` JSON
)
RETURNS json
LANGUAGE SQL
NOT DETERMINISTIC
CONTAINS SQL
SQL SECURITY DEFINER
COMMENT 'UC的用户登录，返回JSON'
BEGIN
    #调用例子
    #SELECT `uc_session_login`(JSON_OBJECT('appid',1,'email','[e-mail]','pwdmd5',MD5('test')),JSON_OBJECT('ipaddress','1.1.1.1'))json
    DECLARE retjson JSON DEFAULT JSON_OBJECT('error',0);
    #密钥表
    DECLARE _keyid INT(10)UNSIGNED;
    DECLARE _secretkey CHAR(32);
    #登录表
    DECLARE _uid INT(10)UNSIGNED;
    DECLARE _username VARCHAR(50);
    DECLARE _password CHAR(32);
    DECLARE _salt CHAR(6);
    #地址记录表
    DECLARE _failedlogins INT(10)UNSIGNED;
    DECLARE _resetwhen TIMESTAMP;#计次重置时间
    #与字段无关的输入
    DECLARE failedlogins_max INT(10)UNSIGNED DEFAULT 3;#密码错误次数上限
    DECLARE failedlogins_timeout INT(10)UNSIGNED DEFAULT 20;#时间范围内清零计数
    DECLARE failedlogins_unlocktime INT(10)UNSIGNED DEFAULT 10;#密码错误次数超限后锁定时间
    #DECLARE srvjson JSON DEFAULT IFNULL(CAST(@srvjson AS CHAR),JSON_OBJECT());#已由会话变量改为函数的参数
    DECLARE secretkey2 VARCHAR(32)DEFAULT IFNULL(srvjson->>'$.secretkey2','');#二级密钥
    DECLARE useripaddress VARCHAR(39)DEFAULT srvjson->>'$.ipaddress';#用户IP地址
    DECLARE req_appid INT UNSIGNED DEFAULT reqjson->>'$.appid';
    DECLARE req_email VARCHAR(50)DEFAULT reqjson->>'$.email';
    DECLARE req_pwdmd5 CHAR(32)DEFAULT reqjson->>'$.pwdmd5';
    #与字段无关的输出
    DECLARE userjson JSON DEFAULT JSON_OBJECT();
    #首先判断IP地址是否已被禁止尝试密码
    #DELETE FROM uc_session_ipaddress WHERE resetwhen<CURRENT_TIMESTAMP();#删除较早的IP
    UPDATE uc_session_ipaddress SET failedlogins=0 WHERE resetwhen<CURRENT_TIMESTAMP();#重置已超时的计数
    SET _failedlogins=0;
    SELECT failedlogins,resetwhen INTO _failedlogins,_resetwhen FROM uc_session_ipaddress WHERE ipaddress=useripaddress FOR UPDATE;
    IF _failedlogins>=failedlogins_max THEN
        RETURN JSON_SET(retjson,'$.errno',-11,'$.message',CONCAT('由于密码错误次数过多，已被锁定。解锁时间：',_resetwhen));
    END IF;
    SELECT uid,username,`password`,salt INTO _uid,_username,_password,_salt FROM uc_members WHERE email=req_email FOR UPDATE;
    IF ISNULL(_uid) THEN RETURN JSON_SET(retjson,'$.errno',-1,'$.message','您输入的E-Mail尚未注册');END IF;
    IF MD5(CONCAT(req_pwdmd5,_salt))<>_password THEN
        INSERT INTO uc_session_loginlog(appid,uid,ipaddress,errno,error)VALUES(req_appid,_uid,useripaddress,-2,'登录密码错误');
        SET @curfailed=_failedlogins+1;#当前计数值
        SET @resetwhen_timeout=TIMESTAMPADD(SECOND,failedlogins_timeout,CURRENT_TIMESTAMP());#清零计数的时间
        IF ISNULL(_resetwhen) THEN#记录为空只能新增
            INSERT INTO uc_session_ipaddress SET ipaddress=useripaddress,failed=CURRENT_TIMESTAMP(),failedlogins=1,faileduid=_uid,resetwhen=@resetwhen_timeout ON DUPLICATE KEY UPDATE failed=VALUES(failed),failedlogins=VALUES(failedlogins),faileduid=VALUES(faileduid),resetwhen=VALUES(resetwhen);
        ELSEIF _failedlogins=0 THEN
            #记录第一次密码错误，并设置新的计数超时时间
            UPDATE uc_session_ipaddress SET failed=CURRENT_TIMESTAMP(),failedlogins=@curfailed,faileduid=_uid,resetwhen=@resetwhen_timeout WHERE ipaddress=useripaddress;
        ELSE
            UPDATE uc_session_ipaddress SET failed=CURRENT_TIMESTAMP(),failedlogins=@curfailed,faileduid=_uid,resetwhen=TIMESTAMPADD(SECOND,failedlogins_unlocktime,CURRENT_TIMESTAMP()) WHERE ipaddress=useripaddress;
        END IF;
        IF @curfailed>=failedlogins_max THEN
            RETURN JSON_SET(retjson,'$.errno',-3,'$.message',CONCAT('由于密码错误次数已达',failedlogins_max,'次，现已被锁定',failedlogins_unlocktime,'秒'));
        END IF;
        RETURN JSON_SET(retjson,'$.errno',-2,'$.message',CONCAT('您已输错',@curfailed,'次密码，如再错',failedlogins_max-@curfailed,'次将被锁定',failedlogins_unlocktime,'秒'));
    END IF;
    #登录校验已通过
    #开始取得secretkey并出hmac
    SELECT id,secretkey INTO _keyid,_secretkey FROM uc_session_keycenter WHERE appid=req_appid AND expired>CURRENT_TIMESTAMP() LIMIT 1;
    IF ISNULL(_keyid) OR ISNULL(_secretkey) THEN RETURN JSON_SET(retjson,'$.errno',-4,'$.message','secretkey获取失败');END IF;
    SET userjson=JSON_SET(userjson,'$.logintime',UNIX_TIMESTAMP(CURRENT_TIMESTAMP()),'$.loginip',useripaddress);
    SET userjson=JSON_SET(userjson,'$.uid',_uid,'$.email',req_email,'$.username',_username,'$.password',_password,'$.salt',_salt);
    IF ISNULL(_resetwhen) THEN#记录为空只能新增
        INSERT INTO uc_session_ipaddress SET ipaddress=useripaddress,failedlogins=0,succeed=CURRENT_TIMESTAMP(),succeeduid=_uid,succeedlogins=1 ON DUPLICATE KEY UPDATE failedlogins=VALUES(failedlogins),succeed=VALUES(succeed),succeeduid=VALUES(succeeduid),succeedlogins=succeedlogins+1;
    ELSE
        UPDATE uc_session_ipaddress SET failedlogins=0,succeed=CURRENT_TIMESTAMP(),succeeduid=_uid,succeedlogins=succeedlogins+1 WHERE ipaddress=useripaddress;
    END IF;
    INSERT INTO uc_session_loginlog(appid,uid,ipaddress,errno,error)VALUES(req_appid,_uid,useripaddress,0,'登录成功');
    SET retjson=JSON_SET(retjson,'$.userjson',CAST(userjson AS CHAR),'$.keyid',_keyid);
    SET retjson=JSON_SET(retjson,'$.hmacsha1',uc_session_hmacsha1(CONCAT(_secretkey,secretkey2),retjson->>'$.userjson'));
    RETURN JSON_SET(retjson,'$.errno',0,'$.message','登录成功');
END