Using the Uniswap Universal Router Without Permission2: A Guide to Web3.py

As a developer using Web3.py and a Geth node-hosted account, you are probably aware of the importance of securely managing private keys. However, when it comes to implementing smart contracts on the Ethereum blockchain, there are certain requirements that must be met to avoid security risks and ensure cross-platform compatibility.

What is Permit2?

Permit2 is a mechanism provided by the Ethereum Foundation that allows developers to sign transactions using a single private key without revealing sensitive information about their wallet or account. This feature was introduced in 2017 as an alternative to the traditional public key signature scheme used on the Ethereum network.

Problem with Permit2 signature generation

Unfortunately, Web3.py does not support the generation of Permit2 signatures. According to Ethereum’s documentation, Permit2 currently only supports decentralized application (dApp) wallets that use the Web3.js library and are configured to use a private key to sign transactions.

Using the Uniswap Universal Router

Fortunately, there is an alternative solution: using the Uniswap Universal Router. The Universal Router allows you to execute smart contract functions on behalf of your Geth node without requiring direct access to your private key or a Permit2 signature.

To get started with the Uniswap Universal Router, follow these steps:

• Install the Uniswap Library: First, install the uniswap library in Python using pip:

pip install uniswap

`

• Configure the Universal Router:

Uniswap provides an easy way to configure the Universal Router. You can do this by creating a “config.json” file with your node’s private key and other configuration information.

Here is an example of a “config.json” file for a Geth node hosted account:

{
"node": {
"host": "
"ports": 8545,
"privateKey": ""
},
"uniswapRouterAddress": "0x... Universal Router Address..."
}

Replace “” with your actual Geth node private key and “…” with the universal router address.

• Create a Web3 provider:

To use the Uniswap universal router, you need to create a Web3 provider that can connect to your Geth node.

Here is an example of using the “eth-apis” library:

from eth import client as EthClient

Create a new client instance with your private key and other configuration information
client = EthClient(config={"node": " "port": 8545, "privateKey": ""})

Get an instance of the Uniswap router
uniswap_router = client.uniswap()

Execute the function using the universal router
def execute_function(func):
result = func()
return result
@execute_function
def my_uniswap_function():

Call the Uniswap function here
pass

• Call the function using the Uniswap universal router:

Now that you have created the Web3 provider and executed your function using Uniswap router, you can call it directly without revealing any sensitive information about your private key or Permit2 signature.

Remember to replace “” with your actual Geth node private key. With this setup, you should be able to execute smart contract functions on behalf of your Geth node hosted account using the Uniswap universal router without generating a Permit2 signature.

Please note that this is an example implementation and may require additional modifications to suit your specific use case. Be sure to review the Ethereum documentation and other resources for more information on deploying smart contracts on the Ethereum network.