swap_tokens
Swap tokens using the CoW Protocol. This is the main high-level function for executing token swaps.
CowContractAddress.VAULT_RELAYER needs to be approved to spend the sell token before calling this function.
async def swap_tokens(
amount: Wei,
account: LocalAccount,
chain: Chain,
sell_token: ChecksumAddress,
buy_token: ChecksumAddress,
safe_address: ChecksumAddress | None = None,
app_data: str = DEFAULT_APP_DATA_HASH,
valid_to: int | None = None,
env: Envs = "prod",
slippage_tolerance: float = 0.005,
partially_fillable: bool = False,
) -> CompletedOrder
Parameters
| Parameter | Type | Required | Default | Description |
|---|
amount | Wei | Yes | - | Amount of tokens to sell (in Wei) |
account | LocalAccount | Yes | - | Ethereum account to sign the order with |
chain | Chain | Yes | - | Blockchain network to execute on |
sell_token | ChecksumAddress | Yes | - | Address of the token to sell |
buy_token | ChecksumAddress | Yes | - | Address of the token to buy |
safe_address | ChecksumAddress | None | No | None | Safe address (uses pre-signature scheme if provided) |
app_data | str | No | DEFAULT_APP_DATA_HASH | Application metadata hash |
valid_to | int | None | No | None | Order expiration (Unix timestamp). Uses quote validity if not set |
env | Envs | No | "prod" | Environment ("prod", "staging") |
slippage_tolerance | float | No | 0.005 | Slippage tolerance (0.005 = 0.5%) |
partially_fillable | bool | No | False | Allow partial fills |
Returns
Returns a CompletedOrder object.
Usage
from web3 import Web3
from eth_account import Account
from cowdao_cowpy.cow.swap import swap_tokens
from cowdao_cowpy.common.chains import Chain
account = Account.from_key("your_private_key")
usdc = Web3.to_checksum_address("0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48")
weth = Web3.to_checksum_address("0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2")
result = await swap_tokens(
amount=Web3.to_wei(1000, "mwei"),
account=account,
chain=Chain.MAINNET,
sell_token=usdc,
buy_token=weth,
slippage_tolerance=0.01,
)
print(f"Order UID: {result.uid}")
print(f"Track order: {result.url}")
With Safe Multi-Sig
safe_address = Web3.to_checksum_address("0x...")
result = await swap_tokens(
amount=Web3.to_wei(1000, "mwei"),
account=account,
chain=Chain.MAINNET,
sell_token=usdc,
buy_token=weth,
safe_address=safe_address,
)
CompletedOrder
A Pydantic model representing a successfully created order.
class CompletedOrder(BaseModel):
uid: UID
url: str
Fields
| Field | Type | Description |
|---|
uid | UID | Unique order identifier (56 bytes) |
url | str | CoW Explorer URL for tracking |
Explorer URLs
The URL points to CoW Explorer based on the chain:
- Mainnet:
https://explorer.cow.fi/ethereum/orders/{uid}
- Gnosis Chain:
https://explorer.cow.fi/gc/orders/{uid}
- Arbitrum:
https://explorer.cow.fi/arb1/orders/{uid}
result = await swap_tokens(...)
order_id = result.uid
explorer_url = result.url
