curl --location --request POST '/EasypayMPSystem/SignServet' \
--data-urlencode 'channelId=' \
--data-urlencode 'tradeTrace=' \
--data-urlencode 'version=' \
--data-urlencode 'sign='
{
"resultCode": "00",
"resultMsg": "string",
"key": "string",
"sign": "string",
"channelId": "string"
}