Running JavaScript code by Terminal: “Uncaught Reference Error: callback is not defined”


Running JavaScript code by Terminal: “Uncaught Reference Error: callback is not defined”



I want to get the output of following JavaScript code (i.e. a signed message) by Terminal (cmd).


Terminal


cmd




function constructPaymentMessage(contractAddress, amount) {
return ethereumjs.ABI.soliditySHA3(
["address", "uint256"],
[contractAddress, amount],
);
}

function signMessage(message, callback) {
web3.personal.sign("0x" + message.toString("hex"), web3.eth.defaultAccount,
callback);
}

// contractAddress is used to prevent cross-contract replay attacks.
// amount, in wei, specifies how much ether should be sent.
function signPayment(contractAddress, amount, callback) {
var message = constructPaymentMessage(contractAddress, amount);
signMessage(message, callback);
}

signPayment('0xca35b7d915458ef540ade6068dfe2f44e8fa733c', 1, callback);



I have already installed ethereumjs-abi that is needed for this code.
So, I have saved this code in a example.js file, however, it seems that I need to add invoking signPayment function in this file.
For example:


ethereumjs-abi


signPayment


signPayment('0xca35b7d915458ef540ade6068dfe2f44e8fa733c', 1, callback);



However, I am not sure about this approach of running .js file by Terminal. And I do not know eventually how to run this file to see its output (i.e. a signed message.)
Meanwhile, apparently signPayment does not return any value as output.


js


Terminal


signPayment


return


output



Here is the message that i receive:


root@ubuntu:/home/s# node sign.js
/home/s/sign.js:20
signPayment('0xca35b7d915458ef540ade6068dfe2f44e8fa733c', 1, callback);
^

ReferenceError: callback is not defined
at Object.<anonymous> (/home/s/sign.js:20:62)
at Module._compile (internal/modules/cjs/loader.js:654:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:665:10)
at Module.load (internal/modules/cjs/loader.js:566:32)
at tryModuleLoad (internal/modules/cjs/loader.js:506:12)
at Function.Module._load (internal/modules/cjs/loader.js:498:3)
at Function.Module.runMain (internal/modules/cjs/loader.js:695:10)
at startup (internal/bootstrap/node.js:201:19)
at bootstrapNodeJSCore (internal/bootstrap/node.js:516:3)



How to get the out put of this JavaScript code ?



Note: I saved the JavaScript code in a .js file (You can see the content of this .js file HERE.) However, when I run this file by node filename.js I receive the error message that I uploaded the screen shot HERE. I do not know where I am going wrong.


JavaScript


.js


node filename.js









By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

-

Popular posts from this blog

PHP contact form sending but not receiving emails

PHP contact form sending but not receiving emails I have created a contact form using PHP to send the data. The form seems to send fine as there are no errors and success message appears, however I am not receving the emails into the designated inbox. I am using PHPMailer as I originally tried just using the php 'mail' command which I now understand is a bit hit and miss. I cannot see why I would not be receving the emails so I would be very grateful for any help that could be given. I'm quite new to PHP so please be patient with me :) <?php use PHPMailerPHPMailerPHPMailer; use PHPMailerPHPMailerException; $msg = ""; if (isset($_POST['submit'])) { require 'phpmailer/src/Exception.php'; require 'phpmailer/src/PHPMailer.php'; require 'phpmailer/src/SMTP.php'; function sendemail ($to, $from, $body) { $mail = new PHPMailer(true); $mail->setFrom($from); $mail->addAddress($to); $ma...
Read more

Do graphics cards have individual ID by which single devices can be distinguished?

Do graphics cards have individual ID by which single devices can be distinguished? I have several graphics cards of the same manufacturer and same model and I want to distinguish them not only by the pcie socket they reside in but by some individual value I can read from the hardware. Is there such value and if so what would it be called and how could I access it? Right now I'm using modern nvidia cards (10xx series) and nvidia inspector.but I'd prefer if there was any value that was also applicable to amd. I have programming and scripting knowledge. I am running Windows 10 1 Answer 1 This is a powershell example to pull information from video cards. The DeviceID is supposed to be unique but only if the manufacturer supports Windows Display Driver Model (WDDM). (I copied this directly from docs.microsoft.com) $strComputer = "." $colItems = get-wmiobject -class "Win32_VideoC...
Read more

iOS Top Alignment constraint based on screen (superview) height

Image
iOS Top Alignment constraint based on screen (superview) height Let's say for example i want my view's top margin be 30 px for iPhone 6s and for the other screen i want to change this constants from 30 to X where X is proportional to total height of screen i.e. 36.5 for iPhone X, 33 for iPhone 6s plus, 25 for iPhone SE And so on .... I know i can take @IBOutlet of NSLayoutConstraint and change it programmatically but what i want is i want to set it like aspect ratio that we have for height width like subview's heigh width is proportional it's superview it changes with super view's height and width @IBOutlet NSLayoutConstraint 2 Answers 2 The constraint you need here is the superView's centerY set multiplier to 0.5 if you want the top anchor's constant to be 0.25 of screen height from the top , so adjust the multiplier according to this logic which is height_of_scre...
Read more