nimbus-eth1/nimbus/db/aristo/aristo_delta/delta_merge.nim

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# 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.
import
std/tables,
Aristo db update for short nodes key edge cases (#1887) * Aristo: Provide key-value list signature calculator detail: Simple wrappers around `Aristo` core functionality * Update new API for `CoreDb` details: + Renamed new API functions `contains()` => `hasKey()` or `hasPath()` which disables the `in` operator on non-boolean `contains()` functions + The functions `get()` and `fetch()` always return a not-found error if there is no item, available. The new functions `getOrEmpty()` and `mergeOrEmpty()` return an an empty `Blob` if there is no such key found. * Rewrite `core_apps.nim` using new API from `CoreDb` * Use `Aristo` functionality for calculating Merkle signatures details: For debugging, the `VerifyAristoForMerkleRootCalc` can be set so that `Aristo` results will be verified against the legacy versions. * Provide general interface for Merkle signing key-value tables details: Export `Aristo` wrappers * Activate `CoreDb` tests why: Now, API seems to be stable enough for general tests. * Update `toHex()` usage why: Byteutils' `toHex()` is superior to `toSeq.mapIt(it.toHex(2)).join` * Split `aristo_transcode` => `aristo_serialise` + `aristo_blobify` why: + Different modules for different purposes + `aristo_serialise`: RLP encoding/decoding + `aristo_blobify`: Aristo database encoding/decoding * Compacted representation of small nodes' links instead of Keccak hashes why: Ethereum MPTs use Keccak hashes as node links if the size of an RLP encoded node is at least 32 bytes. Otherwise, the RLP encoded node value is used as a pseudo node link (rather than a hash.) Such a node is nor stored on key-value database. Rather the RLP encoded node value is stored instead of a lode link in a parent node instead. Only for the root hash, the top level node is always referred to by the hash. This feature needed an abstraction of the `HashKey` object which is now either a hash or a blob of length at most 31 bytes. This leaves two ways of representing an empty/void `HashKey` type, either as an empty blob of zero length, or the hash of an empty blob. * Update `CoreDb` interface (mainly reducing logger noise) * Fix copyright years (to make `Lint` happy)
2023-11-08 12:18:32 +00:00
eth/common,
".."/[aristo_desc, aristo_layers]
# ------------------------------------------------------------------------------
# Public functions
# ------------------------------------------------------------------------------
proc deltaMerge*(
upper: LayerRef; # Think of `top`, `nil` is ok
modUpperOk: bool; # May re-use/modify `upper`
lower: LayerRef; # Think of `balancer`, `nil` is ok
modLowerOk: bool; # May re-use/modify `lower`
): LayerRef =
## Merge argument `upper` into the `lower` filter instance.
##
## Note that the namimg `upper` and `lower` indicate that the filters are
## stacked and the database access is `upper -> lower -> backend`.
##
if lower.isNil:
# Degenerate case: `upper` is void
result = upper
elif upper.isNil:
# Degenerate case: `lower` is void
result = lower
elif modLowerOk:
# Can modify `lower` which is the prefered action mode but applies only
# in cases where the `lower` argument is not shared.
lower.vTop = upper.vTop
layersMergeOnto(upper, lower[])
result = lower
elif not modUpperOk:
# Cannot modify any argument layers.
result = LayerRef(
sTab: lower.sTab, # shallow copy (entries will not be modified)
kMap: lower.kMap,
accLeaves: lower.accLeaves,
stoLeaves: lower.stoLeaves,
vTop: upper.vTop)
layersMergeOnto(upper, result[])
else:
# Otherwise avoid copying some tables by modifying `upper`. This is not
# completely free as the merge direction changes to merging the `lower`
# layer up into the higher prioritised `upper` layer (note that the `lower`
# argument filter is read-only.) Here again, the `upper` argument must not
# be a shared layer/filter.
for (rvid,vtx) in lower.sTab.pairs:
if not upper.sTab.hasKey(rvid):
upper.sTab[rvid] = vtx
for (rvid,key) in lower.kMap.pairs:
if not upper.kMap.hasKey(rvid):
upper.kMap[rvid] = key
for (accPath,leafVtx) in lower.accLeaves.pairs:
if not upper.accLeaves.hasKey(accPath):
upper.accLeaves[accPath] = leafVtx
for (mixPath,leafVtx) in lower.stoLeaves.pairs:
if not upper.stoLeaves.hasKey(mixPath):
upper.stoLeaves[mixPath] = leafVtx
result = upper
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------