nimbus-eth1/nimbus/db/kvt/kvt_utils.nim
Jordan Hrycaj 43e5f428af
Aristo db kvt maintenance update (#1952)
* Update KVT layers abstraction

details:
  modelled after Aristo layers

* Simplified KVT database iterators (removed item counters)

why:
  Not needed for production functions

* Simplify KVT merge function `layersCc()`

* Simplified Aristo database iterators (removed item counters)

why:
  Not needed for production functions

* Update failure condition for hash labels compiler `hashify()`

why:
  Node need not be rejected as long as links are on the schedule. In
  that case, `redo[]` is to become `wff.base[]` at a later stage.

* Update merging layers and label update functions

why:
+ Merging a stack of layers with `layersCc()` could be simplified
+ Merging layers will optimise the reverse `kMap[]` table maps
  `pAmk: label->{vid, ..}` by deleting empty mappings `label->{}` where
  they are redundant.
+ Updated `layersPutLabel()` for optimising `pAmk[]` tables
2023-12-20 16:19:00 +00:00

111 lines
3.2 KiB
Nim

# nimbus-eth1
# Copyright (c) 2023 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.
## Kvt DB -- Common functions
## ==========================
##
{.push raises: [].}
import
eth/common,
results,
./kvt_desc/desc_backend,
"."/[kvt_desc, kvt_layers]
# ------------------------------------------------------------------------------
# Private helpers
# ------------------------------------------------------------------------------
proc getBE(
db: KvtDbRef; # Database
key: openArray[byte]; # Key of database record
): Result[Blob,KvtError] =
## For the argument `key` return the associated value from the backend
## database if available.
##
let be = db.backend
if not be.isNil:
return be.getKvpFn key
err(GetNotFound)
# ------------------------------------------------------------------------------
# Public functions, converters
# ------------------------------------------------------------------------------
proc put*(
db: KvtDbRef; # Database
key: openArray[byte]; # Key of database record to store
data: openArray[byte]; # Value of database record to store
): Result[void,KvtError] =
## For the argument `key` associated the argument `data` as value (which
## will be marked in the top layer cache.)
if key.len == 0:
return err(KeyInvalid)
if data.len == 0:
return err(DataInvalid)
db.layersPut(key, data)
ok()
proc del*(
db: KvtDbRef; # Database
key: openArray[byte]; # Key of database record to delete
): Result[void,KvtError] =
## For the argument `key` delete the associated value (which will be marked
## in the top layer cache.)
if key.len == 0:
return err(KeyInvalid)
db.layersPut(key, EmptyBlob)
ok()
# ------------
proc get*(
db: KvtDbRef; # Database
key: openArray[byte]; # Key of database record
): Result[Blob,KvtError] =
## For the argument `key` return the associated value preferably from the
## top layer, or the database otherwise.
##
if key.len == 0:
return err(KeyInvalid)
let data = db.layersGet(key).valueOr:
return db.getBE key
return ok(data)
proc hasKey*(
db: KvtDbRef; # Database
key: openArray[byte]; # Key of database record
): Result[bool,KvtError] =
## For the argument `key` return the associated value preferably from the
## top layer, or the database otherwise.
##
if key.len == 0:
return err(KeyInvalid)
if db.layersHasKey @key:
return ok(true)
let rc = db.getBE key
if rc.isOk:
return ok(true)
if rc.error == GetNotFound:
return ok(false)
err(rc.error)
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------