Blocknative Python SDK

Install

VirtualEnv QuickStart

$ virtualenv bn
$ . ./bn/bin/activate
(bn) $ pip3 install --upgrade pip
(bn) $ pip3 install blocknative-sdk
(bn) $ curl 'https://raw.githubusercontent.com/blocknative/python-sdk/main/examples/subscribe.py' > subscribe.py
(bn) $ python3 subscribe.py myapikey.key

Manual Install

python3 setup.py install

API Key

To get started using the Blocknative Python SDK you must first obtain an API Key. You can do so by heading over to Blocknative.com!

Usage

Basic usage

from blocknative.stream import Stream
import json

# Initialize the stream
stream = Stream('<API_KEY>')

# Define your transaction handler which has the context of a specific subscription.
async def txn_handler(txn, unsubscribe):
    # Output the transaction data to the console
    print(json.dumps(txn, indent=4))

# Define the address you want to watch
uniswap_v2_address = '0x7a250d5630b4cf539739df2c5dacb4c659f2488d'

# Register the subscription
stream.subscribe_address(uniswap_v2_address, txn_handler)

# Start the websocket connection and start receiving events!
stream.connect()

Unsubscribing

from blocknative.stream import Stream
import json

# Initialize the stream
stream = Stream('<API_KEY>')

# Define your transaction handler
async def txn_handler(txn, unsubscribe):
    if txn['status'] == "confirmed":
        # Output the transaction data to the console
        print(json.dumps(txn, indent=4))

        # Unsubscribe from this subscription
        unsubscribe()

# Define the address you want to watch
uniswap_v2_address = '0x7a250d5630b4cf539739df2c5dacb4c659f2488d'

# Register the subscription
stream.subscribe_address(uniswap_v2_address, txn_handler)

# Start the websocket connection and start receiving events!
stream.connect()

Using Filters

from blocknative.stream import Stream
import json

stream = Stream('<API_KEY>')

async def txn_handler(txn, unsubscribe):
    # This will only get called with transactions that have status of 'confirmed'
    # This is due to the global filter above
    print(json.dumps(txn, indent=4))

uniswap_v2_address = '0x7a250d5630b4cf539739df2c5dacb4c659f2488d'

filters = [{
    'status': 'confirmed'
}]

# Global filter will apply to all of these subscriptions
stream.subscribe_address(curve_fi_address, txn_handler, filter=filters)

# Start the websocket connection and start receiving events!
stream.connect()

Using Global Filters

Similar as above but this time we use global filters which will apply to all subscriptions.

from blocknative.stream import Stream
import json

global_filters = [{
    'status': 'confirmed'
}]

stream = Stream('<API_KEY>', global_filters=global_filters)

async def txn_handler(txn, unsubscribe):
    # This will only get called with transactions that have status of 'confirmed'
    # This is due to the global filter above
    print(json.dumps(txn, indent=4))

uniswap_v2_address = '0x7a250d5630b4cf539739df2c5dacb4c659f2488d'
curve_fi_address = '0xdf5e0e81dff6faf3a7e52ba697820c5e32d806a8'
sushi_swap_address = '0xd9e1ce17f2641f24ae83637ab66a2cca9c378b9f'

# Global filter will apply to all of these subscriptions
stream.subscribe_address(curve_fi_address, txn_handler)
stream.subscribe_address(uniswap_v2_address, txn_handler)
stream.subscribe_address(sushi_swap_address, txn_handler)

# Start the websocket connection and start receiving events!
stream.connect()

Connecting to Binance Smart Chain

from blocknative.stream import Stream
import json

BSC_NETWORK_ID = 56

# Initialize the stream - specify network_id `56` to connect to bsc main
stream = Stream('<API_KEY>', network_id=BSC_NETWORK_ID)

# Define your transaction handler which has the context of a specific subscription.
async def txn_handler(txn, unsubscribe):
    # Output the transaction data to the console
    print(json.dumps(txn, indent=4))

# Define the address you want to watch
pancakeswap_v2_address = '0x10ed43c718714eb63d5aa57b78b54704e256024e'

# Register the subscription
stream.subscribe_address(pancakeswap_v2_address, txn_handler)

# Start the websocket connection and start receiving events!
stream.connect()