Executing a standalone script

If you're looking to run a javascript files to interact with the blockchain, you can use the tsx package to run the files directly from the command line.

This guide will walk you through setting up a simple project using MeshSDK. By the end, you'll have a working environment that can create a wallet, build and sign transactions, and submit them to the blockchain.

In this tutorial, we'll cover:

Creating a package.json file to manage your project dependencies.
Installing the necessary packages, including MeshSDK.
Writing a TypeScript script to create a wallet and send a transaction.
Running your project to see the results.

Let's get started!

Setting up

Create a package.json file

First, create a new `package.json` file in the root of your project with the following content:

{
  "type": "module",
  "dependencies": {},
  "scripts": {
    "dev": "tsx index.ts"
  }
}

Install the necessary packages

Open your terminal and run these commands to install the required packages and MeshSDK:

npm install
npm install tsx @meshsdk/core

Here's how your `package.json` file should look after installing the packages:

{
  "type": "module",
  "dependencies": {
    "@meshsdk/core": "^1.5.18",
    "tsx": "^4.9.4"
  },
  "scripts": {
    "dev": "tsx index.ts"
  }
}

@meshsdk/core: Core functionality for network interactions, wallets, and transactions.
tsx: Allows running TypeScript files directly from the command line.

Make a simple transaction

Create the index.ts file

Next, create a new `index.ts` file in the root of your project and add the following code:

import { BlockfrostProvider, MeshWallet, Transaction } from "@meshsdk/core";

// Set up the blockchain provider with your key
const blockchainProvider = new BlockfrostProvider("YOUR_KEY_HERE");

// Initialize the wallet with a mnemonic key
const wallet = new MeshWallet({
  networkId: 0,
  fetcher: blockchainProvider,
  submitter: blockchainProvider,
  key: {
    type: "mnemonic",
    words: [
      "your", "mnemonic", "...", "here",
    ],
  },
});

// Create and send a transaction
const tx = new Transaction({ initiator: wallet }).sendLovelace(
  "addr_test1qp2k7wnshzngpqw0xmy33hvexw4aeg60yr79x3yeeqt3s2uvldqg2n2p8y4kyjm8sqfyg0tpq9042atz0fr8c3grjmysdp6yv3",
  "1000000"
);

const unsignedTx = await tx.build();
const signedTx = await wallet.signTx(unsignedTx);
const txHash = await wallet.submitTx(signedTx);

Explanation:

Wallet Initialization: The code sets up a new wallet using MeshWallet with a mnemonic key and a blockchain provider.
Transaction Creation: A new transaction is created to send 1 ADA to a specific address. The transaction is built, signed, and submitted to the blockchain.
Output: The transaction hash is logged to the console.

Run Your Application

In the code, you must replace `YOUR_KEY_HERE` with a valid blockfrost key, and replace the mnemonic words with your own. You can visit Blockfrost to get a free API key, and generate a new mnemonic key from the Mesh website.

Finally, start your application by running this command:

npm run dev

If everything is set up correctly, you should see the transaction hash logged to the console. Congratulations! You've successfully created a wallet and sent a transaction using MeshSDK.

You can find the complete code for this guide in the Mesh GitHub repo.