index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/4.0.0/core.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.9-1/md5.js"></script>

    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <script src="https://cdnjs.cloudflare.com/ajax/libs/axios/1.0.0-alpha.1/axios.min.js"
        integrity="sha512-xIPqqrfvUAc/Cspuj7Bq0UtHNo/5qkdyngx6Vwt+tmbvTLDszzXM0G6c91LXmGrRx8KEPulT+AfOOez+TeVylg=="
        crossorigin="anonymous" referrerpolicy="no-referrer"></script>
    <title>Document</title>
</head>
<body>

<script>


let example = {
    m_shop: "1693427769",
    m_orderid: "12345",
    m_amount: "121.00",
    m_curr: "USD",
    m_desc: btoa("Test121"),
    m_key : "12345" // 515100
}


    function hash(string) {
        const utf8 = new TextEncoder().encode(string);
        return crypto.subtle.digest('SHA-256', utf8).then((hashBuffer) => {
            const hashArray = Array.from(new Uint8Array(hashBuffer));
            const hashHex = hashArray
                .map((bytes) => bytes.toString(16).padStart(2, '0'))
                .join('');
            return hashHex;
        });
    }


let sendRequest = (obj)=>{
      let params = "";
        Object.keys(obj).forEach(key=> params +=`${key}=${obj[key]}&`)
        console.log(`https://payeer.com/merchant/?${params}`);
        let url  =  `https://payeer.com/merchant/?${params}`;
        fetch(url , {
            method : "POST",
            cors : "no-cors"
        })
     .then((response) => {
                return response.json();
            })
            .then((data) => {
                console.log("data" , data);
            });
}


let arr =  Object.values(example) ;
   let result =    hash(arr.join(":")).then(res=>{
       example.m_sign =  res.toUpperCase();

       document.body.insertAdjacentHTML('beforeend', `<form method="post" action="https://payeer.com/merchant/">
           <input type = "hidden" name = "m_shop" value = "${example.m_shop}" >
           <input type="hidden" name="m_orderid" value="${example.m_orderid}">
               <input type="hidden" name="m_amount" value="${example.m_amount}">
                   <input type="hidden" name="m_curr" value="${example.m_curr}">
                       <input type="hidden" name="m_desc" value="${example.m_desc}">
                           <input type="hidden" name="m_sign" value="${example.m_sign}">
                               <button id="send" type="submit" name="m_process" value="sendTestRequest">SENDAAAA</button>
                           </form>`);
   });
    
   setTimeout(()=>{
   let btn  =  document.getElementById("send");
       btn && btn.click();}, 2000) 


    </script>
    
</body>
</html>