eth ｜ RPC 的自我封装

由于 web3.py 在速度上无法满足我的需求，所以决定自己封装一下。

• JSON RPC API
• How to call a contract method using the eth_call JSON-RPC API
• Python用以太坊JSON-RPC请求对智能合约进行部署和交易

使用 curl 通过 rpc 进行访问

curl https://bsc-dataseed.binance.org/ -X POST --data '{"jsonrpc":"2.0","method":"eth_getBlockByNumber","params":["latest", false],"id":56}' -x 127.0.0.1:1087

注意看上面的引号。

使用 python 进行协程封装

由于 web3.py 的部分底层并不是协程，所以，想要发挥全部的方法，只能通过多线程。但是，多线程一个是不优雅，另一个就是耗费的资源过多，这里用协程自己封装一套 SDK。

这里仅仅举两个例子。后面看情况，要不要开源相关的轮子。

get_block_info

import asyncio

import aiohttp

from Config.config import proxies, is_proxy


class EvmRequest:
    evm_url = "https://bsc-dataseed.binance.org/"

    def __init__(self):
        pass

    async def get_block_info(self, block_type):
        print(1)
        if is_proxy:
            proxy = proxies
        else:
            proxy = ""
        data = {
            "jsonrpc": "2.0",
            "method": "eth_getBlockByNumber",
            "params": [block_type, False],
            "id": 1
        }
        async with aiohttp.request(method="POST", url=self.evm_url, json=data, proxy=proxy) as r:
            reponse = await r.text(encoding="utf-8")
            return reponse


evm_request = EvmRequest()


def init():
    asyncio.run(run())


async def run():
    functions = []
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))
    functions.append(evm_request.get_block_info("latest"))

    results = await asyncio.gather(*functions)
    print(results)


if __name__ == '__main__':
    init()

注意看 post 的传递数值的方式是 json。

RPC 和自己的合约做交互

不耗费 gas 的 eth_call

生成 data 的其他方式请参考

• solidity | python 编码 abi data

使用 ganache 部署一个简单合约。

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract test{

    function add(uint a,uint b) public pure returns(uint){
        return a + b;
    }
}

这里假设合约地址是: 0x5CF5F2dAFDF7998D9085ffafF5beB1B2b6e4c13c

交互脚本为

import requests
import sha3
import web3
import json

w3 = web3.Web3()
URL = 'http://localhost:8545'
session = requests.Session()

myAddress = '0xF464A67CA59606f0fFE159092FF2F474d69FD675'  # address funded in genesis file

abi = """[{"inputs":[{"internalType":"uint256","name":"a","type":"uint256"},{"internalType":"uint256","name":"b","type":"uint256"}],"name":"add","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"pure","type":"function"}]"""

value1, value2 = 10, 32
result = sha3.keccak_256()
result.update(b"add(uint256,uint256)")
methodId = a = result.hexdigest()[0:8]
param1 = (value1).to_bytes(32, byteorder='big').hex()
param2 = (value2).to_bytes(32, byteorder='big').hex()
data = "0x" + methodId + param1 + param2

json_data = {"jsonrpc": "2.0",
             "method": "eth_call",
             "params": [{'from': myAddress,
                         'to': "0x5CF5F2dAFDF7998D9085ffafF5beB1B2b6e4c13c",
                         'data': data}, "latest"],  # must be an array [value1, value2, ..., valueN]
             "id": 1}

s = session.post(URL,
                 json=json_data,
                 headers={'Content-type': 'application/json'})
print(int(json.loads(s.text).get("result"), 16))

ps: 2022-09-16

这里要提示一下，通过 json-rpc 调用返回的数据，需要自己进行解析，举一个简单的例子。

下面是我调用某一个合约返回的数据。

0x0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000cfcc03efdd344811f5a90000000000000000000000000000000000000000000000bff77b8447ab536e2400000000000000000000000000000000000000000000016ff8d994f69a7293c900000000000000000000000000000000000000000000000156abcf0f93ab3e4f

进行拆开

0x
0000000000000000000000000000000000000000000000000000000000000020
0000000000000000000000000000000000000000000000000000000000000002
00000000000000000000000000000000000000000000cfcc03efdd344811f5a9
0000000000000000000000000000000000000000000000bff77b8447ab536e24
00000000000000000000000000000000000000000000016ff8d994f69a7293c9
00000000000000000000000000000000000000000000000156abcf0f93ab3e4f

然后根据你的合约情况进行相应的解析。

耗费 gas 的合约交互

import json

import requests
import sha3
import web3
from eth_abi import encode
from eth_account import Account
from web3 import Web3

w3 = web3.Web3()
URL = 'http://localhost:8545'
session = requests.Session()

myAddress = ''  # address funded in genesis file

abi = """[]"""


def get_submit_order_data():
    encode_data_info = [...]
    encode_data = encode(['address[]', 'address[]', 'address', 'uint256'], encode_data_info).hex()
    encryption = sha3.keccak_256()
    encryption.update(b"swapCoin(address[],address[],address,uint256)")
    method_hex = encryption.hexdigest()[0:8]
    method_encryption = method_hex

    transaction = {
        "from": "...",  # 发送交易的钱包地址
        'to': "...",  # 合约地址
        "gas": "0x300000",  # Gas 限制
        "gasPrice": Web3.toWei(3, 'gwei'),  # Gas 价格
        'nonce': 2000,  # 交易 nonce
        "data": "0x" + method_encryption + encode_data  # 合约方法和参数的十六进制数据
    }

    return Account.sign_transaction(transaction, "rhino_order.sign_secret")


def submit_order():
    contract_data = get_submit_order_data()
    data = {
        "jsonrpc": "2.0",
        "method": "eth_sendRawTransaction",
        "params": [
            contract_data.rawTransaction.hex()
        ],
        "id": 1
    }

    s = session.post(URL,
                     json=data,
                     headers={'Content-type': 'application/json'})
    print(int(json.loads(s.text).get("result"), 16))


if __name__ == '__main__':
    submit_order()

上述代码只是用来展示用，其主要是与 tomoon | cex2dex 合约再次优化 进行交互。

struct 进行交互

solidity 的代码如下

pragma solidity ^0.8.4;

...


contract MultiSwap {

    ...

    struct coinAmount{
        uint amountIn;
        uint amountOut;
        address receiveAddress;
        address[] routers;
        address[] tokenContracts;
    }

    ...

    function swapExactSupportingFeeCoin(coinAmount memory coin) external onlySign(msg.sender) {
        ...
    }
}

交互如下

import json

import requests
import sha3
import web3
from eth_abi import encode
from eth_account import Account
from web3 import Web3

w3 = web3.Web3()
URL = 'http://localhost:8545'
session = requests.Session()

myAddress = ''  # address funded in genesis file

abi = """[]"""


def get_submit_order_data():
    encode_data_info = [...]
    encode_data = encode(['uint256', 'uint256', 'address', 'address[]', 'address[]'], encode_data_info).hex()
    encryption = sha3.keccak_256()
    encryption.update(b"swapExactSupportingFeeCoin((uint256,uint256,address,address[],address[]))") # 特别注意这是一个 tuple
    method_hex = encryption.hexdigest()[0:8]
    method_encryption = method_hex

    transaction = {
        "from": "...",  # 发送交易的钱包地址
        'to': "...",  # 合约地址
        "gas": "0x300000",  # Gas 限制
        "gasPrice": Web3.toWei(3, 'gwei'),  # Gas 价格
        'nonce': 2000,  # 交易 nonce
        "data": "0x" + method_encryption + encode_data  # 合约方法和参数的十六进制数据
    }

    return Account.sign_transaction(transaction, "rhino_order.sign_secret")


def submit_order():
    contract_data = get_submit_order_data()
    data = {
        "jsonrpc": "2.0",
        "method": "eth_sendRawTransaction",
        "params": [
            contract_data.rawTransaction.hex()
        ],
        "id": 1
    }

    s = session.post(URL,
                     json=data,
                     headers={'Content-type': 'application/json'})
    print(int(json.loads(s.text).get("result"), 16))


if __name__ == '__main__':
    submit_order()