# Wallet Integration

### Implementation Checklist <a href="#implementation-checklist" id="implementation-checklist"></a>

The integration implementation checklist for dApp developers consists of three categories:

1. Frontend features
2. Transactions and wallet interactions
3. Client-side provider

#### Frontend <a href="#frontend" id="frontend"></a>

Make sure to create a wallet-connection button for Metamask and/or Keplr on the frontend of the application. For instance, consider the "Connect to a wallet" button on the interface of [Diffusion Finance](https://app.diffusion.fi/).

#### Transactions <a href="#transactions" id="transactions"></a>

Developers enabling transactions on their dApp have to determine wallet type of the user, create the transaction, request signatures from the corresponding wallet, and finally broadcast the transaction to the network.

**Determining Wallet Type**

Developers should determine whether users are using Keplr or MetaMask. Whether MetaMask or Keplr is installed on the user device can be determined by checking the corresponding `window.ethereum` or `window.keplr` value.

* **For MetaMask**: `await window.ethereum.enable(chainId);`
* **For Keplr**: `await window.keplr.enable(chainId);`

If either `window.ethereum` or `window.keplr` returns `undefined` after `document.load`, then MetaMask (or, correspondingly, Keplr) is not installed. There are several ways to wait for the load event to check the status: for instance, developers can register functions to `window.onload`, or they can track the document's ready state through the document event listener.

After the user's wallet type has been determined, developers can proceed with creating, signing, and sending transactions.

**Create the Transaction**

{% hint style="info" %}
The example below uses the BlockX Testnet `chainID`. For more info, check the BlockX Chain IDs reference document here.
{% endhint %}

Developers can create `MsgSend` transactions.

```javascript
import { createMessageSend } from @tharsis/transactions

const chain = {
    chainId: 50,
    cosmosChainId: 'blockx_50-1',
}

const sender = {
    accountAddress: 'blockx1mx9nqk5agvlsvt2yc8259nwztmxq7zjq50mxkp',
    sequence: 1,
    accountNumber: 9,
    pubkey: 'AgTw+4v0daIrxsNSW4FcQ+IoingPseFwHO1DnssyoOqZ',
}

const fee = {
    amount: '20',
    denom: 'abcx',
    gas: '200000',
}

const memo = ''

const params = {
    destinationAddress: 'blockx1pmk2r32ssqwps42y3c9d4clqlca403yd9wymgr',
    amount: '1',
    denom: 'abcx',
}

const msg = createMessageSend(chain, sender, fee, memo, params)

// msg.signDirect is the transaction in Keplr format
// msg.legacyAmino is the transaction with legacy amino
// msg.eipToSign is the EIP712 data to sign with metamaskjs
```

**Sign and Broadcast the Transaction**

{% hint style="info" %}
The example below uses an BlockX Testnet RPC node.
{% endhint %}

After creating the transaction, developers need to send the payload to the appropriate wallet to be signed ([`msg.signDirect` ](https://docs.keplr.app/api/#sign-direct-protobuf)is the transaction in Keplr format, and `msg.eipToSign` is the [`EIP712`](https://eips.ethereum.org/EIPS/eip-712) data to sign with MetaMask).

#### Connections <a href="#connections" id="connections"></a>

For Ethereum RPC, BlockX gRPC, and/or REST queries, dApp developers should implement providers client-side, and store RPC details in the environment variable as secrets.