This ensures the wallet can properly do an initial sync, a recovery, or
detect if it's on a stale branch before attempting to process new blocks
at tip.
Since the rescan will be triggered synchronously as well, we'll need to
catch the wallet's quit chan when handling rescan batches in order to
allow for clean shutdowns.
In this commit, we address an issue that would cause users to be stuck
in an infinite loop by fetching the same candidate birthday block due to
its height not being updated if the sanity check was attempting to fix
an estimate in the future. We fix this by setting the new candidate
height so that new candidate blocks can be fetched and tested.
In this commit, we remove the wallet dependency from the
birthdaySanityCheck function. Every interaction with the wallet is now
backed by two interfaces, birthdayStore and chainConn. These interfaces
will allow us to increase the test coverage of the birthdaySanityCheck
as now we'll only need to mock out only the necessary functionality.
In this commit, we prevent any further sanity check attempts by the
wallet if its correctness has previously been verified. We do this to
ensure we don't unnecessarily attempt to find a new candidate.
In this commit, we add a sanity check for the wallet's birthday block
before syncing as a result of the migration that populated it for
existing wallets. This is done as the second part to the migration to
ensure we do not miss any relevant events throughout rescans.
The sanity check performs two main checks: whether the birthday block
timestamp reflects a time before the birthday timestamp and whether the
delta between these two timestamps is a reasonable amount. The birthday
block is then found as the first candidate that satisfies both of these
conditions.
In this commit, we avoid notifying clients of transactions that we've
received chain.RelevantTx notifications for, but are not found within
the wallet. This can happen as now we'll prevent adding an unconfirmed
transaction to the wallet that already exists as confirmed. Due to this,
UniqueTxDetails will be unable to find the transaction and return nil,
casuing a panic for potential callers.
In this commit, we alter the behavior for handling chain notifications
within the wallet. The previous code would assume that the channel would
close, but due to now using a ConcurrentQueue to handle notifications,
this assumption no longer stands. Now, we'll stop handling notifications
either once the wallet has or stopped or once the notifications channel
has been closed.
This changes the database access APIs and each of the "manager"
packages (waddrmgr/wstakemgr) so that transactions are opened (only)
by the wallet package and the namespace buckets that each manager
expects to operate on are passed in as parameters.
This helps improve the atomicity situation as it means that many
calls to these APIs can be grouped together into a single
database transaction.
This change does not attempt to completely fix the "half-processed"
block problem. Mined transactions are still added to the wallet
database under their own database transaction as this is how they are
notified by the consensus JSON-RPC server (as loose transactions,
without the rest of the block that contains them). It will make
updating to a fixed notification model significantly easier, as the
same "manager" APIs can still be used, but grouped into a single
atomic transaction.
These notifications were added to support real time updates for
btcgui. As the btcgui project is no longer being developed, there are
no more consumers of this API, and it makes sense to remove them given
their various issues (the largest being that notifiations are sent
unsubscribed to clients that may never be interrested in them).
A new notification server has already been added to the wallet package
to handle notifications in a RPC-server agnostic way. This server is
the means by which the wallet notifies changes for gRPC clients. If
per-client registered notifications are to be re-added for the
JSON-RPC server, they should be integrated with the new notification
server rather than using this legacy code.
This is a rather monolithic commit that moves the old RPC server to
its own package (rpc/legacyrpc), introduces a new RPC server using
gRPC (rpc/rpcserver), and provides the ability to defer wallet loading
until request at a later time by an RPC (--noinitialload).
The legacy RPC server remains the default for now while the new gRPC
server is not enabled by default. Enabling the new server requires
setting a listen address (--experimenalrpclisten). This experimental
flag is used to effectively feature gate the server until it is ready
to use as a default. Both RPC servers can be run at the same time,
but require binding to different listen addresses.
In theory, with the legacy RPC server now living in its own package it
should become much easier to unit test the handlers. This will be
useful for any future changes to the package, as compatibility with
Core's wallet is still desired.
Type safety has also been improved in the legacy RPC server. Multiple
handler types are now used for methods that do and do not require the
RPC client as a dependency. This can statically help prevent nil
pointer dereferences, and was very useful for catching bugs during
refactoring.
To synchronize the wallet loading process between the main package
(the default) and through the gRPC WalletLoader service (with the
--noinitialload option), as well as increasing the loose coupling of
packages, a new wallet.Loader type has been added. All creating and
loading of existing wallets is done through a single Loader instance,
and callbacks can be attached to the instance to run after the wallet
has been opened. This is how the legacy RPC server is associated with
a loaded wallet, even after the wallet is loaded by a gRPC method in a
completely unrelated package.
Documentation for the new RPC server has been added to the
rpc/documentation directory. The documentation includes a
specification for the new RPC API, addresses how to make changes to
the server implementation, and provides short example clients in
several different languages.
Some of the new RPC methods are not implementated exactly as described
by the specification. These are considered bugs with the
implementation, not the spec. Known bugs are commented as such.
If a long reorganize occurs farther back than the last saved recent
block hash (currently max 20 are saved) a full rescan is triggered
since there is no guarantee the previous blocks weren't also removed
in the reorg. In this case, the address manager was set unsynced, but
transaction history was not rolled back as well. This commit corrects
this by unconfirming all transactions but those in the genesis block.
This a refactor of the btcwallet main package to create a new wallet
package.
The main feature of this package is the integration of all the other
wallet components (waddrmgr, txstore, and chain) and the Wallet type is
'runnable', so it will be continuously updating itself against changes
notified by the remote btcd instance.
It also includes several methods which provide access to information
necessary to run a wallet RPC server.