fix: standardize logger names in core modules (phase 1)

[PankajJaisu]

Issue

Fix logging standardization in core modules (Phase 1)

Changes

• Updated 7 core modules to use logging.getLogger(__name__)
• Verified module-specific logging control works correctly
• Ensured no import errors or functionality changes

Testing

1. Unit Tests

Added comprehensive unit tests to verify logger functionality:

pytest -v tests/core/test_libp2p/test_logger_names.py

Results:

• test_logger_names: Verified all logger names are correct
• test_loggers_exist_and_callable: Confirmed loggers work without errors

2. Module-Specific Logging Control

Network Module (Ping Example)

LIBP2P_DEBUG=network:DEBUG python examples/ping/ping.py

Observed logs:

• libp2p.network.swarm logger correctly outputs debug messages
• Listening started and connection information displayed successfully
• Module-specific debug control working as expected

PubSub Module Example

LIBP2P_DEBUG=pubsub:DEBUG python examples/pubsub/pubsub.py

Observed logs:

• libp2p.pubsub.gossipsub logger correctly outputs debug messages
• Node started, topic subscription succeeded, and gossip messages logged
• PubSub debug control functioning properly

Combined Module Logging

LIBP2P_DEBUG=network:DEBUG,pubsub:INFO python examples/pubsub/pubsub.py

• Network modules show DEBUG level messages
• PubSub modules show INFO+ level messages
• Hierarchical logging control verified

3. Logger Name Verification

python -c "
import libp2p.network.swarm
import libp2p.pubsub.gossipsub
print(f'Swarm logger: {libp2p.network.swarm.logger.name}')
print(f'GossipSub logger: {libp2p.pubsub.gossipsub.logger.name}')
"

Output:

Swarm logger: libp2p.network.swarm
GossipSub logger: libp2p.pubsub.gossipsub

4. Basic Functionality Test

cd examples/ping/
python ping.py

• No import errors observed
• All existing functionality works as expected
• No breaking changes introduced

Files Modified

Network & Host Modules

• libp2p/network/swarm.py: logging.getLogger("libp2p.network.swarm") → logging.getLogger(__name__)
• libp2p/host/basic_host.py: logging.getLogger("libp2p.network.basic_host") → logging.getLogger(__name__)
• libp2p/transport/tcp/tcp.py: logging.getLogger("libp2p.transport.tcp") → logging.getLogger(__name__)

PubSub Modules

• libp2p/pubsub/floodsub.py: logging.getLogger("libp2p.pubsub.floodsub") → logging.getLogger(__name__)
• libp2p/pubsub/gossipsub.py: logging.getLogger("libp2p.pubsub.gossipsub") → logging.getLogger(__name__)
• libp2p/pubsub/pubsub.py: logging.getLogger("libp2p.pubsub") → logging.getLogger(__name__)
• libp2p/pubsub/validators.py: logging.getLogger("libp2p.pubsub") → logging.getLogger(__name__)

Verification Checklist

• All 7 target files updated with logging.getLogger(__name__)
• Unit tests added and passing
• Module-specific logging control verified with LIBP2P_DEBUG
• Logger names confirmed to match module paths
• Basic functionality tests pass
• No breaking changes to existing logging behavior
• No import errors or functionality regressions

Learning

Working on this issue provided valuable insights into:

• py-libp2p's logging architecture: Understanding how the custom logging system in libp2p/utils/logging.py enables module-specific control via LIBP2P_DEBUG
• Logger hierarchy importance: How proper logger naming enables granular debugging control across the entire library
• Benefits of __name__: Automatic module path detection eliminates hardcoded strings and ensures consistency
• Testing strategies: Balancing unit tests with integration testing for logging systems

Impact

After these changes, developers now have:

• Granular logging control: LIBP2P_DEBUG=network:DEBUG,pubsub:INFO
• Consistent logger hierarchy: All core modules follow the same naming pattern
• Improved debugging experience: Module-specific logs make troubleshooting more efficient
• Foundation for Phase 2/3: Standardized approach ready for discovery, relay, and DHT modules

References

• based on instruction from: issue_template_logging_phase1.md
• Issue: #906