Evm Extension

Overview

Discover how the EVM Extension for the Credenza Web SDK enhances blockchain interactions by providing streamlined management of the Ethereum Virtual Machine environment. This extension is pivotal for developers aiming to integrate Ethereum-based operations efficiently within their applications.

Installation

npm i @credenza3/core-web-evm-ext

import { EvmExtension } from '@credenza3/core-web-evm-ext'

Create SDK Instance

const sdk = new CredenzaSDK({
  extensions: [
    new EvmExtension({
      chainConfig,
      provider
    }),
  ],
});

Provider

Optional property Provider allows you to pass your own, custom provider (metamask window.ethereum for example) to the EvmExtension configuration. This is basically needed for loginWithSignature method

Define Chain Configuration

To define a chain configuration object for Credenza's EVM Extension, use the following details. The chainConfig object includes several properties, each specifying important parameters for the chain connection.

Here's an example of how you can define a chain configuration object:

const chainConfig = {
  chainId: '0x13881',
  rpcUrl: 'https://polygon-mumbai-bor.publicnode.com',
  displayName: 'Mumbai',
  blockExplorer: 'https://mumbai.polygonscan.com/',
  nativeCurrency: {
    name: 'MATIC',
    symbol: 'MATIC',
    decimals: 18, // defaults to 18
  }
}

Methods and Properties

Evm Login

sdk.evm.loginWithSignature(): Promise<void>

If custom provider was set when initing the extension, you can use sdk.evm.loginWithSignature to authenticate through your provider.

Switch Chain

sdk.evm.switchChain(chainConfig): Promise<void>

To switch chains, use the sdk.evm.switchChain method. This method's implementation depends on the login provider (e.g., Metamask or OAuth).

Get Current Chain Config

sdk.evm.getChainConfig(): Promise<object>

To retrieve the current chain configuration, you can use the sdk.evm.getChainConfig method. This method returns the configuration details of the chain being used.

Here is a code snippet demonstrating how to get the current chain configuration:

const config = await sdk.evm.getChainConfig();
console.log(config);

Get Provider

sdk.evm.getEthersProvider(): Promise<ethers.providers.Provider>

To interact with the blockchain, you need to get the EVM provider or the ethers provider using the EvmExtension. These providers facilitate communication with the chain and the ethers.js library for more complex actions.

Obtaining the EVM provider

sdk.evm.getProvider(): Promise<object>

The above steps provide you with the necessary providers for blockchain interaction and utilizing the ethers.js functionalities. The EvmExtension methods getProvider and getEthersProvider simplify this process.

Complete the wrapping to use ethers.js for performing further operations efficiently.

const provider = await sdk.evm.getEthersProvider();

EVM provider lets you interact directly with the blockchain.

Wrapping the EVM provider with ethers.BrowserProvider:

const evmProvider = await sdk.evm.getProvider();