I am trying to implement an SPV client in python (for my own learning). I want to start by making a simple TCP connection to a full node, but I either cannot get a response to my version message, or to my verack message if the version message goes through. I have referenced this and this is the code that I am trying to run:
#Import dependencies
import socket
import time
import random
import struct
import hashlib
import binascii
import ssl
import socks
# Binary encode the sub-version
def create_sub_version():
sub_version = "/Satoshi:0.7.2/"
return b'\x0F' + sub_version.encode()
# Binary encode the network addresses
def create_network_address(ip_address, port):
network_address = struct.pack('>8s16sH', b'\x01',
bytearray.fromhex("00000000000000000000ffff") + socket.inet_aton(ip_address), port)
return(network_address)
# Create the TCP request object
def create_message(magic, command, payload):
checksum = hashlib.sha256(hashlib.sha256(payload).digest()).digest()[0:4]
return(struct.pack('L12sL4s', magic, command.encode(), len(payload), checksum) + payload)
# Create the "version" request payload
def create_payload_version(peer_ip_address):
version = 60002
services = 1
timestamp = int(time.time())
addr_local = create_network_address("127.0.0.1", 8333)
addr_peer = create_network_address(peer_ip_address, 8333)
nonce = random.getrandbits(64)
start_height = 645953
payload = struct.pack('The server I connect to in the code is among the only ones that would respond to the version message, returning b’7b226a736f6e727063223a2022322e30222c20226572726f72223a207b22636f6465223a202d33323730302c20226d657373616765223a20226d65737361676573206d75737420626520656e636f64656420696e205554462d38227d2c20226964223a206e756c6c7d0a’.
I also tried referencing: this stack exchange question and Ken Shirriff’s github code, but none seem to work, either because I am using python3 or from other causes. I am a beginner in this, so if somebody could help me understand why I cannot get my messages across in the above code or has another implementation in python3, I would be grateful.
