Vault
The Vault module provides utilities for integrating CoW Protocol with Balancer Vault, enabling advanced trading features like internal balance usage and batch swaps.
Constants
VAULT_INTERFACE
A partial ABI interface for the Balancer Vault containing methods for manageUserBalance and batchSwap:
const VAULT_INTERFACE: Interface;
Key Addresses (Mainnet)
| Contract | Address |
|---|
| Balancer Vault | 0xBA12222222228d8Ba445958a75a0704d566BF2C8 |
| CoW Protocol Vault Relayer | 0xC92E8bdf79f0507f65a392b0ab4667716BFE0110 |
Functions
grantRequiredRoles
Grants necessary permissions to the CoW Protocol Vault Relayer.
async function grantRequiredRoles(
vault: Contract,
vaultRelayerAddress: string
): Promise<void>;
This function is intended to be called by the Balancer Vault admin, not by traders.
Balance Types
Users can configure token handling through three balance types:
| Type | Description | Gas Cost |
|---|
| ERC20 | Standard transfers requiring token approval | Standard |
| EXTERNAL | Leverages existing Vault approvals | Reduced |
| INTERNAL | Uses Vault internal balances | Lowest |
Example
import { ethers } from "ethers";
const provider = new ethers.providers.JsonRpcProvider("YOUR_RPC_URL");
// Balancer Vault on mainnet
const vaultAddress = "0xBA12222222228d8Ba445958a75a0704d566BF2C8";
const vaultRelayer = "0xC92E8bdf79f0507f65a392b0ab4667716BFE0110";
// Check internal balance
const vault = new ethers.Contract(vaultAddress, VAULT_INTERFACE, provider);
Internal balance operations have different gas cost characteristics than standard ERC20 transfers. Test thoroughly on testnets before using Vault integration in production.
