UniswapV2 Python

An unofficial Python wrapper for Uniswap V2.

I am not affiliated with Uniswap, use at your own risk.

Features

• Simplistic library capable of interacting with most contract functions and variables.
• Factory - query for information regarding existing pairs.
• Router - add/remove liquidity and perform swaps using either ETH or ERC20 tokens.

Getting Started

This module presents a simplistic interface to Uniswap V2, however I highly recommend you to familiarize yourself with the official documentation before using uniswap-v2-py in order to unlock its full potential and have a better understanding regarding what is actually going on behind the scenes.

Installation:

The module can be installed via pip:

pip install uniswap-v2-py
# or
pip install git+git://github.com/asynctomatic/uniswap-v2-py.git

Alternatively you can clone this repository and install it manually:

git clone https://github.com/asynctomatic/uniswap-v2-py.git
cd uniswap-v2-py
python setup.py install

Configuration

The client expects a web3 provider to be passed to it as an argument. Alternatively you can set the PROVIDER environment variable with your provider of choice.

export PROVIDER=https://mainnet.infura.io/v3/<PROJECT_SECRET>

Documentation

from uniswap.uniswap import UniswapV2Client
client = UniswapV2Client(address, private_key)

from uniswap.uniswap import UniswapV2Client

my_provider = "https://mainnet.infura.io/v3/<PROJECT_SECRET>"
client = UniswapV2Client(address, private_key, provider=my_provider)

Factory Read-Only Methods

get_pair

token_a = "0x20fe562d797a42dcb3399062ae9546cd06f63280"
token_b = "0xc778417E063141139Fce010982780140Aa0cD5Ab"
pair = client.get_pair(token_a, token_b)

Returns the address of the pair for token_a and token_b, if it has been created, else 0x0000000000000000000000000000000000000000.

get_pair_by_index

pair = client.get_pair_by_index(42)

Returns the address of the nth pair (0-indexed) created through the factory, or 0x0000000000000000000000000000000000000000 if not enough pairs have been created yet.

get_num_pairs

num_pairs = client.get_num_pairs()

Returns the total number of pairs created through the factory so far.

get_fee

fee = client.get_fee()

Returns the protocol wide fee. See Protocol Charge Calculation for details.

get_fee_setter

num_pairs = client.get_fee_setter()

Returns the address allowed to change the protocol fee.

Router Read-Only Methods

get_factory

factory = client.get_factory()

Returns the factory address.

get_weth_address

factory = client.get_weth_address()

Returns the canonical WETH address on the Ethereum mainnet, or the Ropsten, Rinkeby, Görli, or Kovan testnets.

State-Changing Methods

add_liquidity

import time

token_a = "0x20fe562d797a42dcb3399062ae9546cd06f63280"
token_b = "0xc778417E063141139Fce010982780140Aa0cD5Ab"
amount_a = 1 * 10**18
amount_b = 2 * 10**17
min_a = int((amount_b / amount_a) * 1.01)  # allow 1% slippage on B/A
min_b = int((amount_a / amount_b) * 1.01)  # allow 1% slippage on A/B
deadline = int(time.time()) + 1000

tx = client.add_liquidity(token_a, token_b, amount_a, amount_b, min_a, min_b, address, deadline)

Adds liquidity to an ERC20-ERC20 pool.

• Always adds assets at the ideal ratio, according to the price when the transaction is executed.
• If a pool for the passed tokens does not exists, one is created automatically, and exactly amount_a/amount_b tokens are added.

add_liquidity_eth

import time

token = "0x20fe562d797a42dcb3399062ae9546cd06f63280"
amount_token = 1 * 10**18
amount_eth = 2 * 10**17
min_token = int((amount_eth / amount_token) * 1.01)  # allow 1% slippage on B/A
min_eth = int((amount_token / amount_eth) * 1.01)  # allow 1% slippage on A/B
deadline = int(time.time()) + 1000

tx = client.add_liquidity_eth(token, amount_token, amount_eth, min_token, min_eth, address, deadline)

Adds liquidity to an ERC20-WETH pool with ETH.

• Always adds assets at the ideal ratio, according to the price when the transaction is executed.
• The amount_eth is sent as msg.value.
• Leftover ETH, if any, is returned to msg.sender.
• If a pool for the passed token and WETH does not exists, one is created automatically, and exactly amount_token/amount_eth tokens are added.

remove_liquidity

liquidity = 1 * 10**16  # amount of liquidity tokens.
tx = client.remove_liquidity(token_a, token_b, liquidity, min_a, min_b, to, deadline)

Removes liquidity from an ERC20-ERC20 pool.

remove_liquidity_eth

liquidity = 1 * 10**16  # amount of liquidity tokens.
tx = client.remove_liquidity(token, liquidity, min_token, min_eth, to, deadline)

Removes liquidity from an ERC-20-WETH pool and returns ETH.

swap_exact_tokens_for_tokens

amount_in = 1 * 10**17
min_amount_out = 1 * 10**15
path = [
    "0x20fe562d797a42dcb3399062ae9546cd06f63280",
    "0xc778417e063141139fce010982780140aa0cd5ab"
]

tx = client.swap_exact_tokens_for_tokens(amount_in, min_amount_out, path, to_address, deadline)

Swaps an exact amount of input tokens for as many output tokens as possible, along the route determined by the path. The first element of path is the input token, the last is the output token, and any intermediate elements represent intermediate pairs to trade through (if, for example, a direct pair does not exist).

Donate

If you found this library useful and want to support my work feel free to donate.

• BTC: 36wpJNSZ4mKHh526D5Zo7qsTvWk8eCkzru
• ETH: 0x1209cEc8CBBa5C67e8A3a154258FEaaCd99D5F20

Disclaimer

I am not affiliated with the Uniswap team nor am I responsible for possible losses of funds resulting from bugs or incorrect usage of this module, use at your own risk.