nimbus-eth1/nimbus/db/kvt/kvt_init/persistent.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.
## Persistent constructor for Kvt DB
## ====================================
##
## This module automatically pulls in the persistent backend library at the
## linking stage (e.g. `rocksdb`) which can be avoided for pure memory DB
## applications by importing `./kvt_init/memory_only` (rather than
## `./kvt_init/persistent`.)
##
{.push raises: [].}
import
results,
../kvt_desc,
"."/[rocks_db, memory_only]
from ../../aristo/aristo_persistent
import GuestDbRef, getRocksDbFamily
export
RdbBackendRef,
memory_only
# ------------------------------------------------------------------------------
# Public database constuctors, destructor
# ------------------------------------------------------------------------------
proc init*[W: MemOnlyBackend|RdbBackendRef](
T: type KvtDbRef;
B: type W;
basePath: string;
guestDb = GuestDbRef(nil);
): Result[KvtDbRef,KvtError] =
## Generic constructor, `basePath` argument is ignored for `BackendNone` and
## `BackendMemory` type backend database. Also, both of these backends
## aways succeed initialising.
##
## If the argument `guestDb` is set and is a RocksDB column familly, the
## `Kvt`batabase is built upon this column familly. Othewise it is newly
## created with `basePath` as storage location.
##
when B is RdbBackendRef:
let rc = guestDb.getRocksDbFamily()
if rc.isOk:
ok KvtDbRef(top: LayerRef(), backend: ? rocksDbBackend rc.value)
else:
ok KvtDbRef(top: LayerRef(), backend: ? rocksDbBackend basePath)
else:
ok KvtDbRef.init B
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------