lnd.xprv/chainntnfs
Olaoluwa Osuntokun bf6001074c
chainntnfs: fix spend notification registration race condition
In this commit, we fix a race condition related to the way we attempt
to query to see if an outpoint has already been spent by the time it’s
registered within the ChainNotifier. If the transaction creating the
outpoint hasn’t made it into the mempool by the time we execute the
GetTxOut call, then we’ll attempt to query for the transaction itself.
In this case, if we query for the transaction, then the block hash
field will be empty as it hasn’t yet made it into a block. Under the
previous logic, we’d then attempt to force a rescan. This is an issue
as the forced rescan will fail since it’ll try to fetch the block hash
of all zeroes.

In this commit, we fix this issue by only entering this “fallback to
rescan” logic iff, the transaction has actually been mined.
2018-01-28 14:48:56 -08:00
..
bitcoindnotify chainntnfs: fix spend notification registration race condition 2018-01-28 14:48:56 -08:00
btcdnotify chainntnfs: fix spend notification registration race condition 2018-01-28 14:48:56 -08:00
neutrinonotify multi: fix several typos in godoc comments 2017-12-17 18:40:05 -08:00
interface_test.go chainntfns: stop neutrino service before closing DB in interface_test.go 2018-01-15 13:59:34 -08:00
interface.go multi: fix several typos in godoc comments 2017-12-17 18:40:05 -08:00
log.go lnd: remove seelog logger 2017-06-25 14:19:56 +01:00
queue_test.go chainntnfs: Implement unbounded concurrent-safe FIFO queue. 2017-11-16 15:15:22 -08:00
queue.go chainntnfs: Implement unbounded concurrent-safe FIFO queue. 2017-11-16 15:15:22 -08:00
README.md multi: fix formatting issues in packge README's 2017-03-27 16:25:25 -07:00
txconfnotifier_test.go chainntnfs: Send negative confirmation notifications. 2017-12-14 19:16:15 -08:00
txconfnotifier.go multi: fix several typos in godoc comments 2017-12-17 18:40:05 -08:00

chainntnfs

Build Status MIT licensed GoDoc

The chainntnfs package implements a set of interfaces which allow callers to receive notifications in response to specific on-chain events. The set of notifications available include:

  • Notifications for each new block connected to the current best chain.
  • Notifications once a txid has reached a specified number of confirmations.
  • Notifications once a target outpoint (txid:index) has been spent.

These notifications are used within lnd in order to properly handle the workflows for: channel funding, cooperative channel closures, forced channel closures, channel contract breaches, sweeping time-locked outputs, and finally pruning the channel graph.

This package is intentionally general enough to be applicable outside the specific use cases within lnd outlined above. The current sole concrete implementation of the ChainNotifier interface depends on btcd.

Installation and Updating

$ go get -u github.com/lightningnetwork/lnd/chainntnfs