@ethereum-tag-service/contracts/README.md

Composable content tagging service for Web3

# Ethereum Tag Service Contracts

Ethereum Tag Service (ETS) is an experimental tagging service running on several EVM testnets.

ETS allows developers to integrate tokenized tags into their applications. These tags can be owned, traded, and used across different platforms, fostering a universal and interconnected tagging system.

## Core Features

- Fully composable tags and tagging data
- Contract-to-contract interaction support
- Relayer interfaces for custom implementations

## Installation

With Hardhat or Truffle:

```bash
npm install @ethereum-tag-service/contracts
```

or with pnpm:

```sh
pnpm install @ethereum-tag-service/contracts
```

## Implementing a Relayer

The IETSRelayer interface provides core tagging functionality:

```solidity
pragma solidity ^0.8.10;

import {IETSRelayer} from "@ethereum-tag-service/contracts/relayers/interfaces/IETSRelayer.sol";

contract MyRelayer is IETSRelayer {
    // Implement required interface methods
}
```

Key Relayer capabilities:

- Apply, replace, and remove tags in tagging record
- Create new tags
- Compute tagging fees
- Ownership and pause controls

## Usage Example

This implementation allows your contract to leverage an existing Relayer's functionality to apply tags through the ETS protocol. The msg.value is forwarded to cover any tagging fees.

```solidity
pragma solidity ^0.8.10;

import {IETSRelayer} from "@ethereum-tag-service/contracts/relayers/interfaces/IETSRelayer.sol";
import {IETS} from "@ethereum-tag-service/contracts/interfaces/IETS.sol";

contract MyContract {
    // Initialize with specific deployed relayer address
    IETSRelayer public relayer = IETSRelayer(0xd2499cf4a47a959217efeacefb7edbd524661f59);

    // Or set via constructor
    constructor(address _relayerAddress) {
        relayer = IETSRelayer(_relayerAddress);
    }

    function applyTags(IETS.TaggingRecordRawInput[] calldata _rawInput) external payable {
        // Forward the tagging request to the relayer
        relayer.applyTags{value: msg.value}(_rawInput);
    }
}

```