Web3 JSON RPC

sync vs async vs batch

import timeit
import asyncio
import contextlib
import requests

from aiohttp import ClientSession

from web3.providers.base import JSONBaseProvider
from web3.providers import HTTPProvider
from web3 import Web3


@contextlib.contextmanager
def profile(name):
	start_time = timeit.default_timer()
	yield
	print('{}: {:.3f}s'.format(name, timeit.default_timer() - start_time))


# synchronously request receipts for given transactions
def sync_receipts(web3, transactions):
	for tran in transactions:
		web3.eth.getTransactionReceipt(tran)

# asynchronous JSON RPC API request
async def async_make_request(session, url, method, params):
    base_provider = JSONBaseProvider()
    request_data = base_provider.encode_rpc_request(method, params)
    async with session.post(url, data=request_data,
                        headers={'Content-Type': 'application/json'}) as response:
        content = await response.read()
    response = base_provider.decode_rpc_response(content)
    return response

async def run(node_address, transactions):
    tasks = []

    # Fetch all responses within one Client session,
    # keep connection alive for all requests.
    async with ClientSession() as session:
        for tran in transactions:
            task = asyncio.ensure_future(async_make_request(session, node_address,
                                                            'eth_getTransactionReceipt',[tran.hex()]))
            tasks.append(task)

        responses = await asyncio.gather(*tasks)

# batch request
def batch(node_address, transactions):
	base_provider = JSONBaseProvider()
	request_data = b'[' + b','.join(
		[base_provider.encode_rpc_request('eth_getTransactionReceipt', [tran.hex()]) for tran in transactions]
		) + b']'
	r = requests.post(eth_node_address, data=request_data, headers={'Content-Type': 'application/json'})
	responses = base_provider.decode_rpc_response(r.content)

if __name__ == "__main__":
    eth_node_address = "http://localhost:8545"
    web3 = Web3(HTTPProvider(eth_node_address))

    transactions = []
    for i in range(0,20):
        block = web3.eth.getBlock(web3.eth.blockNumber-i)
        transactions.extend(block['transactions'])

    with profile('sync'):
	    sync_receipts(web3, transactions)

    with profile('async'):
	    loop = asyncio.get_event_loop()
	    future = asyncio.ensure_future(run(eth_node_address, transactions))
	    loop.run_until_complete(future)

    with profile('batch'):
	    batch(eth_node_address, transactions)