js/get/verifiy_given_message.html


<!-- file:///C:/WWW/APINTIO/js/get/sign_message_with_private_key.html?q=0xf80ce241657b57c495133bde43d281869ab1d08f9e4c28d2c8e17ed1c9283da7|EloiTeaching 

Example result: 
?q=EloiTeaching|0xA3398ad7fB6aE44a542629De9d4426acfb4daE07|0x96f873575cc7a425b44035d0cd09313f092005d9c312b6405d58ad2d29cf398200bd76fdba9da2de86cbad99993292fbc2b1e731a14735f62a6e710149bfdb0b1b
-->
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Sign Message with Web3</title>
    <script src="https://cdn.jsdelivr.net/npm/web3/dist/web3.min.js"></script>

    <style>
        body {
            font-family: 'Courier New', Courier, monospace;
            margin: 0;
            padding: 0;
            background-color: black;
            color: #00FF00;
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
            width: 100vw;
            flex-direction: column;
            box-sizing: border-box;
        }

        #error {
            color: red;
        }  
    </style>
</head>
<body>
    <script>
        (async function() {
            // Parse the query parameter `q`
            const urlParams = new URLSearchParams(window.location.search);
            const qParam = urlParams.get('q');

            if (!qParam) {
                document.getElementById('error').textContent = "Missing ?q= query parameter.";
                return;
            }

            try {
                const web3 = new Web3();
                //EloiTeaching|0xA3398ad7fB6aE44a542629De9d4426acfb4daE07|0x96f873575cc7a425b44035d0cd09313f092005d9c312b6405d58ad2d29cf398200bd76fdba9da2de86cbad99993292fbc2b1e731a14735f62a6e710149bfdb0b1b
                const [message_to_sign, public_address, signed_message] = qParam.split('|'); 
                
                const recoveredAddress = web3.eth.accounts.recover(message_to_sign, signed_message);

                if (recoveredAddress.toLowerCase() === public_address.toLowerCase()) {
                    document.body.innerText = 'VALIDE:TRUE'
                    + '\n' + 'MESSAGE:' + message_to_sign
                    + '\n' + 'PUBLIC_ADDRESS:' + public_address
                    + '\n' + 'SIGNED_MESSAGE:' + signed_message
                    + '\n' + 'RECOVERED_ADDRESS:' + recoveredAddress
                    +" \n "
                    ;
                } else {
                    document.body.innerText = 'VALIDE:FALSE';
                }
            } catch (error) {
                document.body.innerText = 'ERROR:' + error.message;
            }
        })();
    </script>
</body>
</html>