RESTJSONhttps://secure-staging.setu.solutions/https://secure.setu.solutions/application/json。响应正文为 JSON。application/json。GET、DELETE 无正文时不需要。SHA512withRSA 签名的标准 Base64。算法见签名章节。{
"Accept": "application/json",
"Content-Type": "application/json",
"MerchantID": "FX100001",
"Signature": "<SHA512withRSA 的标准 Base64>",
"Timestamp": "1750553505"
}