nimbus-eth1/nimbus/db/aristo/aristo_desc/desc_backend.nim

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Nim

# nimbus-eth1
# Copyright (c) 2023-2024 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
# http://www.apache.org/licenses/LICENSE-2.0)
# * MIT license ([LICENSE-MIT](LICENSE-MIT) or
# http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed
# except according to those terms.
## Aristo DB -- Patricia Trie backend data access
## ==============================================
##
{.push raises: [].}
import
results,
"."/[desc_error, desc_identifiers, desc_structural]
type
GetVtxFn* =
proc(vid: VertexID): Result[VertexRef,AristoError] {.gcsafe, raises: [].}
## Generic backend database retrieval function for a single structural
## `Aristo DB` data record.
GetKeyFn* =
proc(vid: VertexID): Result[HashKey,AristoError] {.gcsafe, raises: [].}
## Generic backend database retrieval function for a single
## `Aristo DB` hash lookup value.
GetTuvFn* =
proc(): Result[VertexID,AristoError] {.gcsafe, raises: [].}
## Generic backend database retrieval function for the top used
## vertex ID.
GetLstFn* =
proc(): Result[SavedState,AristoError]
{.gcsafe, raises: [].}
## Generic last recorded state stamp retrieval function
# -------------
PutHdlRef* = ref object of RootRef
## Persistent database transaction frame handle. This handle is used to
## wrap any of `PutVtxFn`, `PutKeyFn`, and `PutIdgFn` into and atomic
## transaction frame. These transaction frames must not be interleaved
## by any library function using the backend.
PutBegFn* =
proc(): Result[PutHdlRef,AristoError] {.gcsafe, raises: [].}
## Generic transaction initialisation function
PutVtxFn* =
proc(hdl: PutHdlRef; vid: VertexID; vtx: VertexRef)
{.gcsafe, raises: [].}
## Generic backend database bulk storage function, `VertexRef(nil)`
## values indicate that records should be deleted.
PutKeyFn* =
proc(hdl: PutHdlRef; vid: VertexID, key: HashKey)
{.gcsafe, raises: [].}
## Generic backend database bulk storage function, `VOID_HASH_KEY`
## values indicate that records should be deleted.
PutTuvFn* =
proc(hdl: PutHdlRef; vs: VertexID)
{.gcsafe, raises: [].}
## Generic backend database ID generator storage function for the
## top used vertex ID.
PutLstFn* =
proc(hdl: PutHdlRef; lst: SavedState)
{.gcsafe, raises: [].}
## Generic last recorded state stamp storage function. This
## function replaces the currentlt saved state.
PutEndFn* =
proc(hdl: PutHdlRef): Result[void,AristoError] {.gcsafe, raises: [].}
## Generic transaction termination function
# -------------
CloseFn* =
proc(eradicate: bool) {.gcsafe, raises: [].}
## Generic destructor for the `Aristo DB` backend. The argument
## `eradicate` indicates that a full database deletion is requested. If
## passed `false` the outcome might differ depending on the type of
## backend (e.g. in-memory backends will always eradicate on close.)
# -------------
BackendRef* = ref BackendObj
BackendObj* = object of RootObj
## Backend interface.
getVtxFn*: GetVtxFn ## Read vertex record
getKeyFn*: GetKeyFn ## Read Merkle hash/key
getTuvFn*: GetTuvFn ## Read top used vertex ID
getLstFn*: GetLstFn ## Read saved state
putBegFn*: PutBegFn ## Start bulk store session
putVtxFn*: PutVtxFn ## Bulk store vertex records
putKeyFn*: PutKeyFn ## Bulk store vertex hashes
putTuvFn*: PutTuvFn ## Store top used vertex ID
putLstFn*: PutLstFn ## Store saved state
putEndFn*: PutEndFn ## Commit bulk store session
closeFn*: CloseFn ## Generic destructor
proc init*(trg: var BackendObj; src: BackendObj) =
trg.getVtxFn = src.getVtxFn
trg.getKeyFn = src.getKeyFn
trg.getTuvFn = src.getTuvFn
trg.getLstFn = src.getLstFn
trg.putBegFn = src.putBegFn
trg.putVtxFn = src.putVtxFn
trg.putKeyFn = src.putKeyFn
trg.putTuvFn = src.putTuvFn
trg.putLstFn = src.putLstFn
trg.putEndFn = src.putEndFn
trg.closeFn = src.closeFn
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------