Metamask: How to deploy smart contract using truffle and ropsten with Metamask account

Implementing Smart Contracts with Metamask and Truffle

In this article, we will walk through the process of deploying smart contracts using Metamask and Truffle on a Ropsten testnet. We will also cover an issue you might encounter when trying to migrate your contract.

Prerequisites

• Node.js (LTS or newer)

• Truffle CLI (npm install -g truffle)

• Metamask Wallet

Step 1: Create a new project and configure settings

Create a new directory for your project. and initialize it with truffle init. Add the following configuration to your metamask.js file:

const Metamask = require('metamask');
module.exports = {
// Your account name. (e.g. "your_account")
mnemonic: "Your mnemonic",
// The network you want to use
network: {
ropsten,
},
// Metamask wallet password (this will be used as the key for the contract)
password: "",
};

Step 2: Create a new smart contract

Create a new file called “contract.js” and add the following code:

const Web3 = require('web3');
const Web3Contract = require('web3-ethereum-contracts');
class MySmartContract {
constructor() {
this.web3 = new Web3(new Web3.providers.HttpProvider('
const contractAddress = '0xYourContractAddress';
const contractabi = {"version": "1", "name": "MyContract", "functions": ["myFunction"]};
this.contracts = new Web3Contract(this.web3, contractAddress, contractabi);
}
myFunction() {
// Call the function you want to implement
console.log("Hello from my function!");
}
}
module.exports = MySmartContract;

Step 3: Compile and deploy your smart contract

Create a new file called “compile.js” and add the following code:

const Truffle = require('truffe');
module.exports = {
compiler() {
returns new Trufflesolid();
},
};

Step 4: Use Truffle to migrate your contract from Ropsten

Run the following command in your terminal:

npm run compile

This will create a compiled version of your smart contract. Then use Truffle to migrate it from Ropsten:

truffle migration -- ropsten network

Step 5: Update your Metamask account

Update the “metamask.js” file with the following configuration:

const Metamask = require('metamask');
const ropstenAddress = "0xYourRopstenAccount";
const ropstenPassword = "";
module.exports = {
mnemonic: ropstenPassword,
network: {
ropsten: {
address: ropstenAddress,
password: ropstenPassword,
},
},
};

Step 6: Deploy the contract using Metamask

Update the “metamask.js” file with the following configuration:

const Metamask = require('metamask');
const ropstenAddress = "0xYourRopstenAccount";
const ropstenPassword = "";
module.exports = {
mnemonic: ropstenPassword,
network: {
ropsten: {
address: ropstenAddress,
password: ropstenPassword,
},
},
};

Error Message

When you run truffle migrate --network ropsten, you should get an error similar to this:

npm run build

This is because of the compiled version of your contract. It does not include any metadata that Truffle needs for implementation.

Solution

To fix this, you need to update the compiled contract to include the required metadata. You can do this by adding the following code to your compile.js file:

“`javascript

const Web3Contract = require(‘web3-ethereum-contracts’);

class MySmartContract {

constructor() {

const web3 = new Web3(new Web3.providers.HttpProvider(‘

this.

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