How to generate signature
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API Params Example{ "amount": 10000, "orderId": "5f61cf4f41e2b", "orderInfo": "test thanh toan", "bankCode": "VCB", "paymentMethod": "ATM", "clientIp": "103.53.171.140", "extraData": "", "notifyUrl": "http://yourwebsite.com/ipn", "redirectUrl": "http://yourwebsite.com/redirect"}
Params are sorted by alphabet
amount=10000&bankCode=VCB&clientIp=103.53.171.140&extraData=& notifyUrl=http://yourwebsite.com/ipn& orderId=5f61cf4f41e2b&orderInfo=test thanh toan&paymentMethod=ATM&redirectUrl=http://yourwebsite.com/redirect
signature = HMAC_SHA256("amount=10000&bankCode=VCB&clientIp=103.53.171.140& extraData=& notifyUrl=http://yourwebsite.com/ipn& orderId=5f61cf4f41e2b&orderInfo=test thanh toan&paymentMethod=ATM&redirectUrl=http://yourwebsite.com/redirect", YOUR_SECRET_KEY)