Commit Graph

8 Commits

Author SHA1 Message Date
Olaoluwa Osuntokun
86ad6d318e
Merge pull request #889 from wpaulino/chainnotifier-updates
chainntnfs: add incremental update notifications within ChainNotifier
2018-04-12 19:21:26 -07:00
Alex
89e2ba41c9 chainntnfs/bitcoindnotify: rescan blocks manually instead of rewinding 2018-04-06 20:35:27 -06:00
Wilmer Paulino
486694a84e
chainntnfs: add Updates channel field to ConfirmationEvent
In this commit, we add a new Updates channel to our ConfirmationEvent
struct. This channel will be used to deliver updates to a subscriber of
a confirmation notification. Updates will be delivered at every
incremental height of the chain with the number of confirmations
remaining for the transaction to be considered confirmed by the
subscriber.
2018-04-06 00:30:19 -04:00
Johan T. Halseth
9e7e023194
chainntnfs/bitcoind: add bool to RegisterSpendNtfn 2018-04-03 11:24:07 +02:00
Johan T. Halseth
13be19c9ec
chainntnfs/bitcoind: move NotifySpent to after recording the outpoint
This commit moves the call to the bitcoind backend to start watching an
outpoint for spentness to after we have recorded the outpoint in our
list of clients. This is done to avoid a race that we saw using the btcd
backend, and it is probable that it can also happen using bitcoind.
2018-03-28 10:22:41 +02:00
Olaoluwa Osuntokun
9c18c3d9a4
chainntnfs: ensure all block epoch notifications are sent *in order*
In this commit, we fix a lingering bug related to the way that we
deliver block epoch notifications to end users. Before this commit, we
would launch a new goroutine for *each block*. This was done in order
to ensure that the notification dispatch wouldn’t block the main
goroutine that was dispatching the notifications. This method archived
the goal, but had a nasty side effect that the goroutines could be
re-ordered during scheduling, meaning that in the case of fast
successive blocks, then notifications would be delivered out of order.
Receiving out of order notifications is either disallowed, or can cause
sub-systems that rely on these notifications to get into weird states.

In order to fix this issue, we’ll no longer launch a new goroutine to
deliver each notification to an awaiting client. Instead, each client
will now gain a concurrent in-order queue for notification delivery.
Due to the internal design of chainntnfs.ConcurrentQueue, the caller
should never block, yet the receivers will receive notifications in
order. This change solves the re-ordering issue and also minimizes the
number of goroutines that we’ll create in order to deliver block epoch
notifications.
2018-02-09 16:13:28 -08:00
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
Alex
187f59556a multi: add bitcoind drivers and tests 2018-01-15 13:59:34 -08:00