{ "code": "SIGN_ERROR", "detail": { "detail": { "issue": "sign not match" }, "field": "signature", "location": "authorization", "sign_information": { "method": "POST", "sign_message_length": 953, "truncated_sign_message": "POST\n/v3/vehicle/etc/preopen\n1569052402\n1569052402\n{\"sp_app\n", "url": "/v3/vehicle/etc/preopen" } }, "message": "错误的签名，验签失败" }

谁 能给我来个详细的 API签名详解 跪求大神 引导 讲解