[#534] Use UnifiedSpendingKey for shielding and Spending
This commit implements the use of Unified Spending Keys for shielding
and spending as well as rolling Unified Addresses.
Users should obtain addresses by rolling them from the SDK.
USKs replace Sapling Extended Spending keys and TransparentAccountPrivKeys
when shielding or spending
Closes#534
Co-authored-by: Kris Nuttycombe <kris@nutty.land>
* Fix rebase issues
* PR Suggestion. Make `lastError` an Optional
* Fix test `testReOrgRemovesOutboundTxAndIsNeverMined`
Co-authored-by: Kris Nuttycombe <kris@nutty.land>
this introduces several types under UnifiedAddress `ReceiverTypecodes`
and `UnifiedAddress.Errors` to host possible errors on third-party
generated UAs and their composition
Implement extracting the typecodes from a UA
This PR creates data types for Addresses and Keys so that they are
not represented by Strings anymore. This avoids mistakenly use
the wrong keys because they are all alike for the type system.
New Protocols:
=============
StringEncoded -> Protocol that makes a type can be expressed in an
string-encoded fashion either for UI or Interchange purposes.
Undescribable -> A protocol that implements methods that override default
decriptions used by debuggers, loggers and event trackers to avoid types
conforming to it to be leaked to logs.
Deleted Protocols:
==================
UnifiedFullViewingKey --> turned into a struct.
UnifiedAddress --> turned into a struct
new Error Type:
================
````
enum KeyEncodingError: Error {
case invalidEncoding
}
````
This error is thrown when an Address or Key type (addresses are public
keys in the end) can be decoded from their String representation,
typically upon initialization from a User input.
New Types:
=========
SaplingExtendedSpendingKey -> Type for Sapling Extended Full Viewing Keys
this type will be replaced with Unified Spending Keys soon.
SaplingExtendedFullViewingKey -> Extended Full Viewing Key for Sapling.
Maintains existing funcionality. Will be probably deprecated in favor of
UFVK.
TransparentAccountPrivKey -> Private key for transparent account. Used
only for shielding operations. Note: this will probably be deprecated soon.
UnifiedFullViewingKey -> Replaces the protocol that had the same name.
TransparentAddress -> Replaces a type alias with a struct
SaplingAddress --> Represents a Sapling receiver address. Comonly called zAddress. This address corresponds to the Zcash Sapling shielded pool.
Although this it is fully functional, we encourage developers to
choose `UnifiedAddress` before Sapling or Transparent ones.
UnifiedAddress -> Represents a UA. String-encodable and Equatable. Use of
UAs must be favored instead of individual receivers for different pools.
This type can't be decomposed into their Receiver types yet.
Recipient -> This represents all valid receiver types to be used as
inputs for outgoing transactions.
````
public enum Recipient: Equatable, StringEncoded {
case transparent(TransparentAddress)
case sapling(SaplingAddress)
case unified(UnifiedAddress)
````
The wrapped concrete receiver is a valid receiver type.
Deleted Type Aliases:
=====================
The following aliases were deleted and turned into types
````
public typealias TransparentAddress = String
public typealias SaplingShieldedAddress = String
````
Changes to Derivation Tool
==========================
DerivationTool has been changed to accomodate this new types and
remove Strings whenever possible.
Changes to Synchronizer and CompactBlockProcessor
=================================================
Accordingly these to components have been modified to accept the
new types intead of strings when possible.
Changes to Demo App
===================
The demo App has been patch to compile and work with the new types.
Developers must consider that the use (and abuse) of forced_try and
forced unwrapping is a "license" that maintainers are using for the
sake of brevity. We consider that clients of this SDK do know how to
handle Errors and Optional and it is not the objective of the demo
code to show good practices on those matters.
Closes#461
Lukas Korba
Francisco Gindre
Francisco Gindre