3.0 的说我的key太短是为啥

[Dandelion246]

复制的配置未修改 'login_type' => 'mpo', 'signer_key' => 'oP0qmqzHS4Vvml5a', 'public_key' => 'file://path/public.key', 'private_key' => 'file://path/private.key', 'expires_at' => 3600, 'refresh_ttL' => 7200, 'leeway' => 0, 'signer' => 'HS256', 'type' => 'Header', 'auto_refresh' => false, 'iss' => 'webman.client.admin',

error: Lcobucci\JWT\Signer\InvalidKeyProvided: Key provided is shorter than 256 bits, only 96 bits provided in /Users/prw/Desktop/Quick/peng/webman/vendor/lcobucci/jwt/src/Signer/InvalidKeyProvided.php:39

[yuanzhihai]

'signer_key' => hash("sha256", $string);