Deploy an EVM contract

Overview

The x/evm Warden module allows executing Ethereum Virtual Machine (EVM) contracts charged by Evmos. They are written in Solidity.

This guide explains how to create and deploy a simple "Hello World" Solidity smart contract on the Warden chain. Since it's intended for testing purposes, you'll be running a local chain.

Prerequisites

Before you start, complete the following prerequisites:

Install Node.js and npm by running the following command:
```
brew install node
```
Install Truffle globally:
```
npm install -g truffle
```
Run a local chain and make sure you have wardend correctly installed.

In Step 3, you'll need your Warden private key. You can get it by executing the command below. Specify your key name (local account name).
```
wardend keys export my-key-name --unarmored-hex --unsafe
```
tip
If you used a just script or a devnet snapshot to run your node, the local account name is shulgin. You can check the names of available keys by running wardend keys list.

1. Create an EVM project

Create a new directory /warden-smart-contract for your project and navigate there:
```
mkdir warden-smart-contract
cd warden-smart-contract
```
Initialize a new Truffle project:
```
truffle init
```

2. Create a smart contract

In the /warden-smart-contract/contracts directory, create a new file HelloWarden.sol with the following contents:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract HelloWarden {
    string public message;

    constructor() {
        message = "Hello, Warden!";
    }

    function setMessage(string memory newMessage) public {
        message = newMessage;
    }

    function getMessage() public view returns (string memory) {
        return message;
    }
}

3. Configure Truffle

Install HDWalletProvider:
```
npm install @truffle/hdwallet-provider
```

In the /warden-smart-contract directory, find the truffle-config.js file and update it with the code below.

Replace your_private_key with your actual private key (see Prerequisites).

const HDWalletProvider = require('@truffle/hdwallet-provider');

// Your private key (keep this secret and never commit it to version control!)
const PRIVATE_KEY = 'your_private_key';

module.exports = {
networks: {
    warden: {
    provider: function() {
        return new HDWalletProvider(PRIVATE_KEY, "http://localhost:8545");
    },
    network_id: 1337, // Match any network id
    host: "127.0.0.1",
    port: 8545,
    gas: 5500000,
    gasPrice: 20000000000,  // 20 gwei
    },
},
compilers: {
    solc: {
    version: "0.8.0",
    }
}
};

4. Create a migration script

In /warden-smart-contract/migrations, create a new file 2_deploy_hello_warden.js with the following s:

const HelloWarden = artifacts.require("HelloWarden");

module.exports = function(deployer) {
deployer.deploy(HelloWarden);
};

5. Compile the contract

To compile your contract, run this command:

truffle compile

You'll see an output similar to the following:

Compiling your contracts...
===========================
> Compiling ./contracts/HelloWarden.sol
> Artifacts written to /build/contracts
> Compiled successfully using:
   - solc: 0.8.0+commit.c7dfd78e.Emscripten.clang

6. Deploy the contract

To deploy the contract, run this:

truffle migrate --network warden

You should see the following output, confirming the successful deployment.

Compiling your contracts...
===========================
> Everything is up to date, there is nothing to compile.


Starting migrations...
======================
> Network name:    'warden'
> Network id:      1337
> Block gas limit: 4294967295 (0xffffffff)


2_deploy_hello_warden.js
========================

   Deploying 'HelloWarden'
   -----------------------
   > transaction hash:    0x14ed62fcb105a3b5d315738767f288101f4db2d13ee4924a217090080abe0fef
   > Blocks: 0            Seconds: 0
   > contract address:    0x2AAbb1a9b8EdE05f183FfD90A324ce02A349F6e5
   > block number:        2993
   > block timestamp:     1725617534
   > account:             0x6Ea8aC1673402989e7B653aE4e83b54173719C30
   > balance:             9999999.83499999999011708
   > gas used:            2750000 (0x29f630)
   > gas price:           20 gwei
   > value sent:          0 ETH
   > total cost:          0.055 ETH

   > Saving artifacts
   -------------------------------------
   > Total cost:               0.055 ETH

Summary
=======
> Total deployments:   1
> Final cost:          0.055 ETH

7. Interact with the contract

Open the Truffle console:
```
truffle console --network warden
```

In the console, interact with your contract:

let instance = await HelloWarden.deployed()
let message = await instance.getMessage()
console.log(message) // Should print "Hello, Warden!"
await instance.setMessage("Hello, EVM on Warden!")
message = await instance.getMessage()
console.log(message) // Should print "Hello, EVM on Warden!"

The console log should first print Hello, Warden! and then Hello, EVM on Warden!

If you encounter any issues, please reach out to us in Discord or Twitter.

Happy coding! 🚀

Overview​

Prerequisites​

1. Create an EVM project​

2. Create a smart contract​

3. Configure Truffle​

4. Create a migration script​

5. Compile the contract​

6. Deploy the contract​

7. Interact with the contract​