@cowprotocol/hook-dapp-lib
v1.3.1
Published
CoW Swap Hook Dapp Library. Allows you to develop pre/post hooks dapps for CoW Protocol.
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CoW Protocol hooks
CoW Hooks allow users to call arbitrary Ethereum action before and/or after swap.
For example: before swap give a permission to CoW Protocol smart-contract and after swap bridge tokens to another chain.
Docs: https://docs.cow.fi/cow-protocol/tutorials/hook-dapp
CoW Hooks Dapp library
CoW Swap provides an opportunity to use external dapps to build hooks.
So, you can put a link to some hook-daap and it will be automatically integrate in CoW Swap!
This library is for developers who are interested in developing dapps for CoW Hooks. It provides:
EIP-1193provider to interact with a user walletHookDappContextwhich contains environment parameters (chainId, account, etc.) and current order parameters (sell token, validTo, etc.)
And it expects calling two callbacks:
addHook()when a hook data is ready and can be added to an ordereditHook()when hook parameters were changed
Quick start
npm install @cowprotocol/hook-dapp-lib --saveyarn add @cowprotocol/hook-dapp-libLet's create a simple hook-dapp that will check the COW token balance of the order creator.
<html>
<body>
<button id="actionButton">Add hook</button>
<script>
import { initCoWHookDapp, HookDappContext } from '@cowprotocol/hook-dapp-lib'
const COW_TOKEN_ADDRESS = '0xdef1ca1fb7fbcdc777520aa7f396b4e015f497ab'
// ERC20.balanceOf(account)
const CALL_DATA = (account: string) => `0x70a08231000000000000000000000000${account.slice(2)}`
let context: HookDappContext | null = null
const { actions } = initCoWHookDapp({ onContext: (_context) => context = _context })
document.getElementById('actionButton').addEventListener('click', () => {
if (!context) {
console.log('App is not loaded yet, please wait a bit.')
return
}
if (context.hookToEdit) {
// Implement a logic for editing an existing hook
// And call actions.editHook() with new parameters
}
actions.addHook({
hook: {
target: COW_TOKEN_ADDRESS,
callData: CALL_DATA(context.account),
gasLimit: '32000'
}
})
})
</script>
</body>
</html>Developers
Test
nx test hook-dapp-libBuild the library
nx build hook-dapp-lib