Sometimes when performing an initial sync, the remote
node isn't able to pull messages off the wire because
of long running tasks and queues are saturated. With
a shorter write timeout, we will give up trying to send
messages and teardown the connection, even though the
peer is still active.
This commit adds asynchronous starting of peers,
in order to avoid potential DOS vectors. Currently,
we block with the server's mutex while peers exchange
Init messages and perform other setup. Thus, a remote
peer that does not reply with an init message will
cause server to block for 15s per attempt.
We also modify the startup behavior to spawn
peerTerminationWatchers before starting the
peer itself, ensuring that a peer is properly
cleaned up if the initialization fails. Currently,
failing to start a peer does not execute the bulk
of the teardown logic, since it is not spawned
until after a successful Start occurs.
This commit adds additional synchronization logic to
WaitForDisconnect, such that it can be spawned before
Start has been executed by the server. Without
modification, the current version will return
immediately since no goroutines will have been
spawned.
To solve this, we modify WaitForDisconnect to block until:
1) the peer is disconnected,
2) the peer is successfully started,
before watching the waitgroup.
In the first case, the waitgroup will block until all
(if any) spawned goroutines have exited. Otherwise, if
the Start is successful, we can switch to watching the
waitgroup, knowing that waitgroup counter is positive.
In a previous commit, we modified our fee rates to be sat/kw internally
as it was possible that the estimated fee rate was not enough to
properly broadcast the transaction. To remedy this, we decided to add a
fee floor, but this would only be enforced when querying the fee
estimator. In this commit, we attempt to do the same thing, but for fee
rates input manually by the user.
Tests for the case where a chain backend skips a series of blocks, such that the notifier's best block is out of date. Also tests the case where a notifier's best block has been reorged out of the chain.
This tests the case where a client registers for block notifications with an outdated best block, to ensure that the client is properly caught up on the blocks that it has missed.
Switches all ChainNotifier parameters to be TestChainNotifiers. This allows access to the extra testing methods provided by the TestChainNotifier interface.
TestChainNotifier wraps the ChainNotifier interface to allow adding additional testing methods with access to private fields in the notifiers. These testing methods are only compiled when the build tag "debug" is set. UnsafeStart allows starting a notifier with a specified best block.
UnsafeStart is useful for the purpose of testing cases where a notifier's best block is out of date when it receives a new block.
In this commit, we thread through a link's quit channel into
routeAsync, the primary helper method allowing links to send
htlcPackets through the switch. This is intended to remove
deadlocks from happening, where the link is synchronously
blocking on forwarding packets to the switch, but also
needs to shutdown.
This commit adds a test that verifies Stop does not block
if the link is concurrently forwarding incoming Adds to
the switch. This test fails prior to the commits that
thread through the link's quit channel.
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.
This prevents the situation where we notify clients about a newly connected block, and then the block connection itself fails. We also want to set our best block in between connecting the block and notifying clients, in case a client makes queries about the new block they have received.
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 fix a bug recently introduced where we would
construct the parameters required to connect to a bitcoind backend, but
never actually started the connection.
