Crate zcash_client_sqlite

An SQLite-based Zcash light client.

zcash_client_sqlite contains complete SQLite-based implementations of the WalletRead, WalletWrite, and BlockSource traits from the zcash_client_backend crate. In combination with zcash_client_backend, it provides a full implementation of a SQLite-backed client for the Zcash network.

Design

The light client is built around two SQLite databases:

• A cache database, used to inform the light client about new CompactBlocks. It is read-only within all light client APIs except for init_cache_database which can be used to initialize the database.

• A data database, where the light client’s state is stored. It is read-write within the light client APIs, and assumed to be read-only outside these APIs. Callers MUST NOT write to the database without using these APIs. Callers MAY read the database directly in order to extract information for display to users.

Feature flags

• multicore (enabled by default) — Enables multithreading support for creating proofs and building subtrees.
• orchard — Enables support for storing data related to the sending and receiving of Orchard funds.
• test-dependencies — Exposes APIs that are useful for testing, such as proptest strategies.
• transparent-inputs — Enables receiving transparent funds and sending to transparent recipients
• serde — Enables serde derives for certain types.

Experimental features

• unstable — Exposes unstable APIs. Their behaviour may change at any time.
• expensive-tests — A feature used to isolate tests that are expensive to run. Test-only.
• pczt-tests — A feature used to enable PCZT-specific tests without interfering with the protocol-specific flags. Test-only.

Modules

chain

Functions for enforcing chain validity and handling chain reorgs.

error

Error types for problems that may arise when reading or storing wallet data to SQLite.

util

Types that should be part of the standard library, but aren’t.

wallet

Functions for querying information in the wallet database.

Structs

AccountUuid

Unique identifier for a specific account tracked by a WalletDb.

BlockDb

A handle for the SQLite block source.

FsBlockDbunstable

A block source that reads block data from disk and block metadata from a SQLite database.

GapLimitstransparent-inputs

A data structure that can be used to configure custom gap limits for use in transparent address rotation.

ReceivedNoteId

An opaque type for received note identifiers.

SqlTransaction

A wrapper for a SQLite transaction affecting the wallet database.

UtxoId

A newtype wrapper for sqlite primary key values for the utxos table.

WalletDb

A wrapper for the SQLite connection to the wallet database, along with a capability to read the system from the clock. A WalletDb encapsulates the full set of capabilities that are required in order to implement the WalletRead, WalletWrite and WalletCommitmentTrees traits.

Enums

FsBlockDbErrorunstable

Errors that can be generated by the filesystem/sqlite-backed block source.