Files
py-libp2p/libp2p/discovery/bootstrap/bootstrap.py
2025-08-29 17:34:47 +05:30

313 lines
12 KiB
Python

import logging
from multiaddr import Multiaddr
from multiaddr.resolvers import DNSResolver
import trio
from libp2p.abc import ID, INetworkService, PeerInfo
from libp2p.discovery.bootstrap.utils import validate_bootstrap_addresses
from libp2p.discovery.events.peerDiscovery import peerDiscovery
from libp2p.network.exceptions import SwarmException
from libp2p.peer.peerinfo import info_from_p2p_addr
from libp2p.peer.peerstore import PERMANENT_ADDR_TTL
logger = logging.getLogger("libp2p.discovery.bootstrap")
resolver = DNSResolver()
DEFAULT_CONNECTION_TIMEOUT = 10
class BootstrapDiscovery:
"""
Bootstrap-based peer discovery for py-libp2p.
Connects to predefined bootstrap peers and adds them to peerstore.
"""
def __init__(self, swarm: INetworkService, bootstrap_addrs: list[str]):
"""
Initialize BootstrapDiscovery.
Args:
swarm: The network service (swarm) instance
bootstrap_addrs: List of bootstrap peer multiaddresses
"""
self.swarm = swarm
self.peerstore = swarm.peerstore
self.bootstrap_addrs = bootstrap_addrs or []
self.discovered_peers: set[str] = set()
self.connection_timeout: int = DEFAULT_CONNECTION_TIMEOUT
async def start(self) -> None:
"""Process bootstrap addresses and emit peer discovery events in parallel."""
logger.info(
f"Starting bootstrap discovery with "
f"{len(self.bootstrap_addrs)} bootstrap addresses"
)
# Show all bootstrap addresses being processed
for i, addr in enumerate(self.bootstrap_addrs):
logger.debug(f"{i + 1}. {addr}")
# Validate and filter bootstrap addresses
self.bootstrap_addrs = validate_bootstrap_addresses(self.bootstrap_addrs)
logger.info(f"Valid addresses after validation: {len(self.bootstrap_addrs)}")
# Use Trio nursery for PARALLEL address processing
try:
async with trio.open_nursery() as nursery:
logger.debug(
f"Starting {len(self.bootstrap_addrs)} parallel address "
f"processing tasks"
)
# Start all bootstrap address processing tasks in parallel
for addr_str in self.bootstrap_addrs:
logger.debug(f"Starting parallel task for: {addr_str}")
nursery.start_soon(self._process_bootstrap_addr, addr_str)
# The nursery will wait for all address processing tasks to complete
logger.debug(
"Nursery active - waiting for address processing tasks to complete"
)
except trio.Cancelled:
logger.debug("Bootstrap address processing cancelled - cleaning up tasks")
raise
except Exception as e:
logger.error(f"Bootstrap address processing failed: {e}")
raise
logger.info("Bootstrap discovery startup complete - all tasks finished")
def stop(self) -> None:
"""Clean up bootstrap discovery resources."""
logger.info("Stopping bootstrap discovery and cleaning up tasks")
# Clear discovered peers
self.discovered_peers.clear()
logger.debug("Bootstrap discovery cleanup completed")
async def _process_bootstrap_addr(self, addr_str: str) -> None:
"""Convert string address to PeerInfo and add to peerstore."""
try:
try:
multiaddr = Multiaddr(addr_str)
except Exception as e:
logger.debug(f"Invalid multiaddr format '{addr_str}': {e}")
return
if self.is_dns_addr(multiaddr):
resolved_addrs = await resolver.resolve(multiaddr)
if resolved_addrs is None:
logger.warning(f"DNS resolution returned None for: {addr_str}")
return
peer_id_str = multiaddr.get_peer_id()
if peer_id_str is None:
logger.warning(f"Missing peer ID in DNS address: {addr_str}")
return
peer_id = ID.from_base58(peer_id_str)
addrs = [addr for addr in resolved_addrs]
if not addrs:
logger.warning(f"No addresses resolved for DNS address: {addr_str}")
return
peer_info = PeerInfo(peer_id, addrs)
await self.add_addr(peer_info)
else:
peer_info = info_from_p2p_addr(multiaddr)
await self.add_addr(peer_info)
except Exception as e:
logger.warning(f"Failed to process bootstrap address {addr_str}: {e}")
def is_dns_addr(self, addr: Multiaddr) -> bool:
"""Check if the address is a DNS address."""
return any(protocol.name == "dnsaddr" for protocol in addr.protocols())
async def add_addr(self, peer_info: PeerInfo) -> None:
"""
Add a peer to the peerstore, emit discovery event,
and attempt connection in parallel.
"""
logger.debug(
f"Adding peer {peer_info.peer_id} with {len(peer_info.addrs)} addresses"
)
# Skip if it's our own peer
if peer_info.peer_id == self.swarm.get_peer_id():
logger.debug(f"Skipping own peer ID: {peer_info.peer_id}")
return
# Filter addresses to only include IPv4+TCP (only supported protocol)
ipv4_tcp_addrs = []
filtered_out_addrs = []
for addr in peer_info.addrs:
if self._is_ipv4_tcp_addr(addr):
ipv4_tcp_addrs.append(addr)
else:
filtered_out_addrs.append(addr)
# Log filtering results
logger.debug(
f"Address filtering for {peer_info.peer_id}: "
f"{len(ipv4_tcp_addrs)} IPv4+TCP, {len(filtered_out_addrs)} filtered"
)
# Skip peer if no IPv4+TCP addresses available
if not ipv4_tcp_addrs:
logger.warning(
f"❌ No IPv4+TCP addresses for {peer_info.peer_id} - "
f"skipping connection attempts"
)
return
# Add only IPv4+TCP addresses to peerstore
self.peerstore.add_addrs(peer_info.peer_id, ipv4_tcp_addrs, PERMANENT_ADDR_TTL)
# Only emit discovery event if this is the first time we see this peer
peer_id_str = str(peer_info.peer_id)
if peer_id_str not in self.discovered_peers:
# Track discovered peer
self.discovered_peers.add(peer_id_str)
# Emit peer discovery event
peerDiscovery.emit_peer_discovered(peer_info)
logger.info(f"Peer discovered: {peer_info.peer_id}")
# Connect to peer (parallel across different bootstrap addresses)
logger.debug("Connecting to discovered peer...")
await self._connect_to_peer(peer_info.peer_id)
else:
logger.debug(
f"Additional addresses added for existing peer: {peer_info.peer_id}"
)
# Even for existing peers, try to connect if not already connected
if peer_info.peer_id not in self.swarm.connections:
logger.debug("Connecting to existing peer...")
await self._connect_to_peer(peer_info.peer_id)
async def _connect_to_peer(self, peer_id: ID) -> None:
"""
Attempt to establish a connection to a peer with timeout.
Uses swarm.dial_peer to connect using addresses stored in peerstore.
Times out after self.connection_timeout seconds to prevent hanging.
"""
logger.debug(f"Connection attempt for peer: {peer_id}")
# Pre-connection validation: Check if already connected
if peer_id in self.swarm.connections:
logger.debug(
f"Already connected to {peer_id} - skipping connection attempt"
)
return
# Check available addresses before attempting connection
available_addrs = self.peerstore.addrs(peer_id)
logger.debug(f"Connecting to {peer_id} ({len(available_addrs)} addresses)")
if not available_addrs:
logger.error(f"❌ No addresses available for {peer_id} - cannot connect")
return
# Record start time for connection attempt monitoring
connection_start_time = trio.current_time()
try:
with trio.move_on_after(self.connection_timeout):
# Log connection attempt
logger.debug(
f"Attempting connection to {peer_id} using "
f"{len(available_addrs)} addresses"
)
# Use swarm.dial_peer to connect using stored addresses
await self.swarm.dial_peer(peer_id)
# Calculate connection time
connection_time = trio.current_time() - connection_start_time
# Post-connection validation: Verify connection was actually established
if peer_id in self.swarm.connections:
logger.info(
f"✅ Connected to {peer_id} (took {connection_time:.2f}s)"
)
else:
logger.warning(
f"Dial succeeded but connection not found for {peer_id}"
)
except trio.TooSlowError:
logger.warning(
f"❌ Connection to {peer_id} timed out after {self.connection_timeout}s"
)
except SwarmException as e:
# Calculate failed connection time
failed_connection_time = trio.current_time() - connection_start_time
# Enhanced error logging
error_msg = str(e)
if "no addresses established a successful connection" in error_msg:
logger.warning(
f"❌ Failed to connect to {peer_id} after trying all "
f"{len(available_addrs)} addresses "
f"(took {failed_connection_time:.2f}s)"
)
# Log individual address failures if this is a MultiError
if (
e.__cause__ is not None
and hasattr(e.__cause__, "exceptions")
and getattr(e.__cause__, "exceptions", None) is not None
):
exceptions_list = getattr(e.__cause__, "exceptions")
logger.debug("📋 Individual address failure details:")
for i, addr_exception in enumerate(exceptions_list, 1):
logger.debug(f"Address {i}: {addr_exception}")
# Also log the actual address that failed
if i <= len(available_addrs):
logger.debug(f"Failed address: {available_addrs[i - 1]}")
else:
logger.warning("No detailed exception information available")
else:
logger.warning(
f"❌ Failed to connect to {peer_id}: {e} "
f"(took {failed_connection_time:.2f}s)"
)
except Exception as e:
# Handle unexpected errors that aren't swarm-specific
failed_connection_time = trio.current_time() - connection_start_time
logger.error(
f"❌ Unexpected error connecting to {peer_id}: "
f"{e} (took {failed_connection_time:.2f}s)"
)
# Don't re-raise to prevent killing the nursery and other parallel tasks
def _is_ipv4_tcp_addr(self, addr: Multiaddr) -> bool:
"""
Check if address is IPv4 with TCP protocol only.
Filters out IPv6, UDP, QUIC, WebSocket, and other unsupported protocols.
Only IPv4+TCP addresses are supported by the current transport.
"""
try:
protocols = addr.protocols()
# Must have IPv4 protocol
has_ipv4 = any(p.name == "ip4" for p in protocols)
if not has_ipv4:
return False
# Must have TCP protocol
has_tcp = any(p.name == "tcp" for p in protocols)
if not has_tcp:
return False
return True
except Exception:
# If we can't parse the address, don't use it
return False