curl --location --request POST 'http://dev-cn.your-api-server.com/api/apps/trade/v2/merchant_cancel_book' \
--header 'access_token: xxxxxxxx' \
--header 'Content-Type: application/json' \
--data-raw '{
"book_id" : "mock_book_id",
"cancel_reason" : "xxxxxx"
}'
"extra": {
"sub_error_code": 0,
"sub_description": "success",
"logid": "2022092115392201020812109511046",
"now": 1663745962686,
"error_code": 0,
"description": "success"
}
预约单id,len(book_id) <= 64 byte