This change makes it easier for third parties to make use of the Unified
key infrastructure without incurring a dependency upon the rest of the
`zcash_client_backend` interfaces.
This modifies the `compute_balance` method to operate in a
bundle-oriented fashion, which simplifies the API and makes it easier to
elide Orchard functionality in the case that the `orchard` feature is
not enabled.
This unification allows us to better isolate transparent-input dependent
functionality. Previously, `TransparentInputSource` could not be placed
under a feature flag because the interface was needed for proposal
deserialization; by instead making the transparent input source methods
flag-dependent, we can correctly produce an error when proposal
deserializaiton attempts to select transparent inputs and the feature
flag is off.
We plan to also introduce a similar flag to gate access to Sapling
functionality. Since introduction of Orchard functionality is still
nascent, it's the correct time to introduce this isolation, before
there's more functionality that needs to be isolated in this fashion.
`ReceivedNote` now allows Orchard notes to be represented as received
notes. As part of this change, received notes now track whether they
were received using internally- or externally-scoped viewing keys.
This eliminates the need to trial-regenerate notes using the wallet's
IVKs to determine scope at spend time.
Public methods for mutation of these fields have been provided that
perform checking for overflow of the valid monetary range as part
of their operation.
Prior to this change, it's necessary to implement the entirety of the
`WalletRead` trait in order to be able to use the input selection
functionality provided by `zcash_client_backend::data_api::input_selection`.
This change factors out the minimal operations required for transaction
proposal construction to better reflect the principle of least authority
and make the input selection code reusable in more contexts.
In order to minimize the operations of the newly-created `InputSource`
and `ShieldingSource` traits, this change also removes the
`min_confirmations` field from transaction proposals, in favor of
storing explicit target and anchor heights. This has the effect of
limiting the lifetime of transaction proposals to `PRUNING_DEPTH -
min_confirmations` blocks.
This fixes an API issue whereby it was possible to execute a `Proposal`
with a different value of `min_confirmations` than that with which the
`Proposal` was constructed.
`StandardFeeRule` is an enumeration of the standard fees that have
existed in the history of Zcash zips. It is provided to simplify
transition to new fee strategies; legacy elements of this enumeration
are introduced already-deprecated.
The existing API limited change outputs to having only a single memo
repeated across each change output. This change makes it so that each
proposed change output can have its own associated memo, and leaves it
up to the input selector to determine how requested change memos are
associated with change outputs.
In order to use `uint64` for amounts that must be nonnegative in the
`proposal.proto` file, it is useful to update fee and change computation
to use `NonNegativeAmount` where possible.
When scanning, a wallet only needs to update balance and transaction
information shown to users when the scan has resulted in a change to
wallet state. This modifies `scan_cached_blocks` to return the range of
block heights actually scanned, along with the counts of notes spent and
received by the wallet in that range.
Fixes#918
Kris Nuttycombe
Andrew Arnott
Kris Nuttycombe
Jack Grigg
Matthew Watt
sasha
Matthew Watt