> For the complete documentation index, see [llms.txt](https://docs.envio.dev/llms.txt).

# Scaffold-Eth-2 Envio Extension

## Introduction

The [Scaffold-ETH 2](https://scaffoldeth.io/extensions) Envio extension makes indexing your deployed smart contracts as simple as possible. Generate a boilerplate indexer for your deployed contracts with a single click and start indexing their events immediately.

With this extension, you get:
- 🔍 **Automatic indexer generation** from your deployed contracts
- 📊 **Status dashboard** with links to Envio metrics and database
- 🔄 **One-click regeneration** to update the indexer when you deploy new contracts
- 📈 **GraphQL API** for querying your indexed blockchain data

## Prerequisites

Before starting, ensure you have the following installed:

- **[Node.js v20](https://nodejs.org/en/download/current)** _(v20 or newer required)_
- **[pnpm](https://pnpm.io/installation)** _(for Envio indexer)_
- **[Docker Desktop](https://www.docker.com/products/docker-desktop/)** _(required to run the Envio indexer locally)_
- **[Yarn](https://yarnpkg.com/getting-started/install)** _(for Scaffold-ETH)_

## Step 1: Create a New Scaffold-ETH 2 Project with Envio Extension

To create a new Scaffold-ETH 2 project with the Envio extension already integrated:

```bash
npx create-eth@latest -e enviodev/scaffold-eth-2-extension
```


## Step 2: Start the Local Blockchain

Navigate to your project directory and start the local blockchain:

```bash
cd your-project-name
yarn chain
```

This will start a local blockchain node for development.

## Step 3: Deploy Your Contracts

In a new terminal window, navigate to your project directory and deploy the default smart contracts:

```bash
cd your-project-name
yarn deploy
```

This will deploy the default contracts to the local blockchain. This step is optional and can also be done once you've created your own smart contracts and deployed them using `yarn deploy`.

## Step 4: Start Scaffold-ETH Frontend

From your project directory, start the Scaffold-ETH frontend:

```bash
yarn start
```

This will start the Scaffold-ETH frontend at `http://localhost:3000`.

## Step 5: Generate the Indexer

Navigate to the Envio page in your Scaffold-ETH frontend at `http://localhost:3000/envio` and click the **"Generate"** button. This should only be done once you've created a smart contract and ran `yarn deploy`. This will create the boilerplate indexer from your deployed contracts.

<img src="/img/scaffold-eth-2-envio-page.png" alt="Scaffold-ETH 2 Envio Dashboard" width="100%"/>

The Envio page also includes a helpful "How to Use" section with step-by-step instructions.

## Step 6: Start the Indexer

Navigate to the Envio package directory and start the indexer:

```bash
cd packages/envio
pnpm dev
```

This will begin indexing your contract events.

## Regenerating the Indexer

When you deploy new contracts or make changes to existing ones, you'll need to regenerate the indexer:

### Via Frontend Dashboard
1. Go to the Envio page at `http://localhost:3000/envio`
2. Click "Generate" to regenerate the boilerplate indexer

### Via Command Line
```bash
cd packages/envio
pnpm update
pnpm codegen
```

> **Note:** Regenerating will overwrite any custom handlers, config, and schema changes, creating a fresh boilerplate indexer based on your deployed contracts. After regenerating, you'll need to stop the running indexer (Ctrl+C) and restart it with `pnpm dev` for the changes to take effect.