Getting error while connecting to smart contract using web 3
Question
i referred https://medium.com/@amkurian/interacting-with-ethereum-smart-contracts-through-web3-js-e0efad17977 to connect to smart contract, where i want to simply access the get() method of the smart contract.
Here is the code:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Web 3</title>
<link rel="stylesheet" type="text/css" href="index.css">
<script src="./node_modules/web3/dist/web3.min.js"></script>
</head>
<body>
<div class="container">
<h1>First Smart Contract</h1>
<h2 id="instructor"></h2>
<label for="name" class="col-lg-2 control-label">Instructor Name</label>
<input id="name" type="text">
<label for="name" class="col-lg-2 control-label">Instructor Age</label>
<input id="age" type="text">
<button id="button">Update Instructor</button>
</div>
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js "></script>
<script>
if (typeof web3 !== 'undefined') {
web3 = new Web3(web3.currentProvider);
}
else {
// set the provider you want from Web3.providers
web3 = new Web3(new Web3.providers.HttpProvider("http://my_ip_address:8545"));
}
web3.eth.defaultAccount = 'account address';
var CoursesContract = web3.eth.contract(my abi);
var Courses = CoursesContract.at('my smart contract address');
console.log(Courses.getName());
</script>
</body>
</html>
But i m getting the below error in the console:
web3.min.js:1 Uncaught Error: CONNECTION ERROR: Couldn't connect to node
http://my ip here:8545.
at Object.InvalidConnection (web3.min.js:1)
at i.send (web3.min.js:1)
at s.send (web3.min.js:1)
at _.e [as call] (web3.min.js:1)
at c.call (web3.min.js:1)
at c.execute (web3.min.js:1)
at index.html:40
Kindly help
1 answers
solution1
0 2018-06-21 17:03:47
EDITED Answer:
Run the command ganache-cli and leave it running. Replace http://my_ip_address:8545 with http://localhost:8545/
This will resolve your problem.
Previous Deleted Answer:
The problem is, presumably, your ganache local node not being configured properly, or not running. Can you show the output of running ganache-cli in the commandline?
And, where you have 'my_ip_address' You can simple replace that with http://localhost:8545/
Can you also, in a browse, go to http://localhost:8545 If it works, you should see a '400 Bad Request'. If it does not work, you will see a site cannot be reached.
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