This resolves the situation where a notifier's chain backend skips a series of blocks, causing the notifier to need to dispatch historical block notifications to clients.
Additionally, if the current notifier's best block has been reorged out, this logic enables the notifier to rewind to the common ancestor between the current chain and the outdated best block and dispatches notifications from the ancestor.
If the chain backend misses telling the notifier about a series of disconnected blocks, the notifier is now able to disconnect the tip to its new best block.
If a client passes in their best known block when registering for block notifications, check to see if it's behind our best block. If so, dispatch the missed block notifications to the client.
This is necessary because clients that persist their best known block can miss new blocks while registering for notifications.
Clients can optionally pass their best block known into RegisterBlockEpochNtfn. This enables the notifiers to catch up clients on blocks they may have missed.
In this commit, we update the RegisterSpendNtfn method to also take the
prev output script of the item that we're attempting to watch for. This
change is required due to the recent modifications in the neutrino
protocol (BIP 158 + 157). With the new protocol, we'll match on the
script, but then dispatch notifications based on the precise outpoint
that matches.
In this commit, we prep for an upcoming final change to BIP 158. The
change results in the txid no longer being included in the regular
filter. As a result, neutrino will now need to match based on the output
script of the transaction that we wish to receive confirmation
notifications for.
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.
This commit modifies two of the main methods in the ChainNotifier
interface to be more light client friendly. In order to do so, we now
tack on an extra parameter to the methods: heightHint. This value
represents the earliest known height that the chain should be scanned
when attempting to do a dispatch from historical data.
All tests have also been updated to use these new parameters properly
when excising the expected behavior of each interface implementation.
When iterating with the ChainNotifier, it currently isn’t possible to
cancel a non-dispatched yet active notificaiton intent. As a result,
this can be rather wasteful in many parts of lnd which my repeatedly
create a new spend notification depending on if/when a peer is
connected or not.
In order to fix this, we add a new `Cancel func()` field to both the
`BlockEpochEvent` and `SpendEvent` structs. This new closure attribute
allows the caller to cancel the yet-to-be-dispathed event, allowing the
ChainNotifier to free up resources.
This commit makes a large number of minor changes concerning API usage
within the deamon to match the latest version on the upstream btcsuite
libraries.
The major changes are the switch from wire.ShaHash to chainhash.Hash,
and that wire.NewMsgTx() now takes a paramter indicating the version of
the transaction to be created.
This commit modifies the ChainNotifier interface, specifically the
ConfirmationEvent struct to now return additional details concerning
the exact location in the chain that the transaction was confirmed at.
This information will be very useful within the new routing package, as
within the network, channels are identified via their channel-ID which
is a compact encoding of: blockHeight | txIndex | outputIndex
This commit updates the documentation for the ChainNotifier interface
to specify that all implementation MUST be able to support dispatching
the same notification to multiple clients.
This commit refactors the existing chainntnfns package in order to
allow more easily allow integration into the main system, by allowing
one to gain access to a set of end-to-end tests for a particular
ChainNotifier implementation.
In order to achieve this, the existing set of tests for the only
concrete implementation (`BtcdNoitifer`) have been refactored to test
against all “registered” notifier interfaces registered. This is
achieved by creating the concept of a “driver” for each concrete
`ChainNotifer` implementation. Once a the package of a particular
driver is imported, solely for the side effects, the init() method
automatically registers the driver.
Additionally, the documentation in various areas of the package have
been cleaned up a bit.
