Note: This question is related to this : "Updated :" How to see "output" of "web3.personal.sign" in "browser"? ("Method personal_sign not supported")
I do following steps to sign a message using web3.personal.sign. However, I am not to MetaMask. (Note: apparently, web3.personal.sign is not supported by testRPC.)
Here are steps that I do:
(1) I open cmd and run testrpc
(2) I click on MetaMask icon and selecting localhost 8545
(3) I select one of private keys generated by testrpc
(4) I select import account from MetaMask and paste this private key in text box of Paste your private key string here
(5) now balance of this address is 100 eth
(6) I insert this address (public key) in web3.personal.sign function to sign the message (Please see the full code below)
(7) I open html file by Google Chrome
(8) I receive this messages : No web3? You should consider trying MetaMask! and Error: Method personal_sign not supported. Here is screen shot: https://ibb.co/i93oRy
Here is the full code for signing a message using web3.personal.sign:
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>EthereumJS - Browser Example</title>
</head>
<body>
<script src="https://rawgit.com/ethereumjs/browser-builds/master/dist/ethereumjs-abi/ethereumjs-abi-0.6.5.js"></script>
<script src="https://rawgit.com/ethereum/web3.js/develop/dist/web3.js"></script>
<script src="https://cdn.jsdelivr.net/gh/ethereum/web3.js/dist/web3.min.js"></script>
<script>
window.addEventListener('load', function() {
// Checking if Web3 has been injected by the browser (Mist/MetaMask)
if (typeof web3 !== 'undefined') {
// Use Mist/MetaMask's provider
web3 = new Web3(web3.currentProvider);
} else {
console.log('No web3? You should consider trying MetaMask!')
// fallback - use your fallback strategy (local node / hosted node + in-dapp id mgmt / fail)
web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
}
// var Web3
// web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
function constructPaymentMessage(contractAddress, amount)
{
return ethereumjs.ABI.soliditySHA3(
["address", "uint256"],
[contractAddress, amount],
);
}
var message = constructPaymentMessage("message to be signed", 100);
console.log(message);
web3.personal.sign("0x" + message.toString("hex"), "0x01e7D1D50804fDc2fD5A134081076A8E487Ca747", function(err, signature) {
console.log(signature);
console.log(err);
// Be sure to make use of the signature only here.
// It will not be defined until this callback is invoked.
});
})
</script>
</body>
</html>
Apparently, I am not connected to MetaMask and if so, How can I solve this problem?
Here is screen shot of MetaMask when is opened and connected to localhost 8545 (As you can see the balance of testRPC address is 100 eth) :
Web3 Detected! MetamaskInpageProviderscreen shot : ibb.co/gZfwDd