Introduction to Clients & Transports #

Clients #

A Client provides access to a subset of Actions.

A Client in the context of viem is similar to an Ethers.js Provider.

There are three types of Clients in viem:

• A Public Client which provides access to Public Actions, such as getBlockNumber and getBalance.
• A Wallet Client which provides access to Wallet Actions, such as sendTransaction and signMessage.
• A Test Client which provides access to Test Actions, such as mine and impersonate.

Transports #

A Client is instantiated with a Transport, which is the intermediary layer that is responsible for executing outgoing requests (ie. RPC requests).

There are three types of Transports in viem:

• A HTTP Transport that executes requests via a HTTP JSON-RPC API.
• A WebSocket Transport that executes requests via a WebSocket JSON-RPC API.
• A Custom Transport that executes requests via an EIP-1193 Provider (such as window.ethereum).