Olaoluwa Osuntokun b8ca876409 discovery/test: add comprehensive tests for state handler error exits
Add comprehensive test coverage to verify that state handler errors cause
the channelGraphSyncer goroutine to exit cleanly without entering endless
retry loops. These tests use mutation testing principles to ensure they
would fail if the fixes were removed.

TestGossipSyncerStateHandlerErrors is a table-driven test covering four
scenarios: context cancellation and peer disconnect during syncingChans
state, and context cancellation and network errors during queryNewChannels
state. Each test case verifies both attempt count (no endless loop) and
clean shutdown (no deadlock).

TestGossipSyncerProcessChanRangeReplyError verifies that errors from
processChanRangeReply in the waitingQueryRangeReply state cause clean
exit. This test sends multiple malformed messages and checks that only
the first is processed before the goroutine exits, using channel queue
depth to detect if the goroutine is still running.

All tests are race-detector clean and use mutation testing validation:
removing any of the error return statements causes the corresponding
tests to fail, confirming the tests properly verify the fixes.
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Lightning Network Daemon

Release build MIT licensed Irc Godoc Go Report Card

The Lightning Network Daemon (lnd) - is a complete implementation of a Lightning Network node. lnd has several pluggable back-end chain services including btcd (a full-node), bitcoind, and neutrino (a new experimental light client). The project's codebase uses the btcsuite set of Bitcoin libraries, and also exports a large set of isolated re-usable Lightning Network related libraries within it. In the current state lnd is capable of:

  • Creating channels.
  • Closing channels.
  • Completely managing all channel states (including the exceptional ones!).
  • Maintaining a fully authenticated+validated channel graph.
  • Performing path finding within the network, passively forwarding incoming payments.
  • Sending outgoing onion-encrypted payments through the network.
  • Updating advertised fee schedules.
  • Automatic channel management (autopilot).

Lightning Network Specification Compliance

lnd fully conforms to the Lightning Network specification (BOLTs). BOLT stands for: Basis of Lightning Technology. The specifications are currently being drafted by several groups of implementers based around the world including the developers of lnd. The set of specification documents as well as our implementation of the specification are still a work-in-progress. With that said, the current status of lnd's BOLT compliance is:

  • BOLT 1: Base Protocol
  • BOLT 2: Peer Protocol for Channel Management
  • BOLT 3: Bitcoin Transaction and Script Formats
  • BOLT 4: Onion Routing Protocol
  • BOLT 5: Recommendations for On-chain Transaction Handling
  • BOLT 7: P2P Node and Channel Discovery
  • BOLT 8: Encrypted and Authenticated Transport
  • BOLT 9: Assigned Feature Flags
  • BOLT 10: DNS Bootstrap and Assisted Node Location
  • BOLT 11: Invoice Protocol for Lightning Payments

Developer Resources

The daemon has been designed to be as developer friendly as possible in order to facilitate application development on top of lnd. Two primary RPC interfaces are exported: an HTTP REST API, and a gRPC service. The exported APIs are not yet stable, so be warned: they may change drastically in the near future.

An automatically generated set of documentation for the RPC APIs can be found at api.lightning.community. A set of developer resources including guides, articles, example applications and community resources can be found at: docs.lightning.engineering.

Finally, we also have an active Slack where protocol developers, application developers, testers and users gather to discuss various aspects of lnd and also Lightning in general.

First-time contributors are highly encouraged to start with code review first, before creating their own Pull Requests.

Installation

In order to build from source, please see the installation instructions.

Docker

To run lnd from Docker, please see the main Docker instructions

IRC

  • irc.libera.chat
  • channel #lnd
  • webchat

Safety

When operating a mainnet lnd node, please refer to our operational safety guidelines. It is important to note that lnd is still beta software and that ignoring these operational guidelines can lead to loss of funds.

Security

The developers of lnd take security very seriously. The disclosure of security vulnerabilities helps us secure the health of lnd, privacy of our users, and also the health of the Lightning Network as a whole. If you find any issues regarding security or privacy, please disclose the information responsibly by sending an email to security at lightning dot engineering, preferably encrypted using our designated PGP key (91FE464CD75101DA6B6BAB60555C6465E5BCB3AF) which can be found here.

Further reading

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