python

gistfile1.txt

#this uses the uniswap smart contract to find the exchange rate on uniswap from one token to another

import requests, logging, json, os, time, sys
from web3 import Web3

tokens = json.load(open('abi/kyber_currencies.json', 'r'))["data"]
tokenarray = {}
for i in tokens: tokenarray[i["symbol"].lower()] = (Web3.toChecksumAddress(i["address"]), i["decimals"])
#print(tokenarray)	

web3 = Web3(Web3.HTTPProvider('https://mainnet.infura.io/v3/4766db13619a4175aa7cf834d3eeae42'))
erc20abi = json.load(open('abi/erc20.json', 'r'))


uniswapabi= json.load(open('abi/UniswapV2Router02.json', 'r'))
uniswapcontract = Web3.toChecksumAddress('0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D')
uniswap = web3.eth.contract(abi=uniswapabi, address=uniswapcontract)

#for item in dir(uniswap.functions): print(item) # inspect properties and methods of web3 contract object

ethprovider_url = 'https://mainnet.infura.io/v3/4766db13619a4175aa7cf834d3eeae42' # infura project ID
baseaccount = Web3.toChecksumAddress('0x2e9f3eb1e287b1081f4bc8ef5adbb80f063ae19e') # pubkey

amount = Web3.toWei(sys.argv[3], 'ETHER')

def main():
	afterslippage = getuniswapprice(tokenarray[sys.argv[1]][0], tokenarray[sys.argv[2]][0], amount)
	output = sys.argv[3] + " " + sys.argv[1] + " after slippage will get " + str(afterslippage) + " " + sys.argv[2]
	print(output)

def getuniswapprice(token1address, token2address, amount):
	expectedreturn = uniswap.functions.getAmountsOut(amount, (token1address, token2address)).call({'from': baseaccount})[1]
	return float(expectedreturn/10**tokenarray[sys.argv[2]][1])

if __name__ == '__main__':
    main()