nimbus-eth2/beacon_chain/trusted_state_snapshots.nim

48 lines
1.7 KiB
Nim

import
ospaths, chronos, json_serialization, strformat,
spec/[datatypes, crypto, digest, beaconstate], beacon_chain_db, conf
const
WEAK_SUBJECTVITY_PERIOD* = uint64(4 * 30 * 24 * 60 * 60) div SECONDS_PER_SLOT
# TODO: This needs revisiting.
# Why was the validator WITHDRAWAL_PERIOD altered in the spec?
proc obtainTrustedStateSnapshot*(db: BeaconChainDB): Future[BeaconState] {.async.} =
# In case our latest state is too old, we must obtain a recent snapshot
# of the state from a trusted location. This is explained in detail here:
# https://notes.ethereum.org/oaQV3IF5R2qlJuW-V1r1ew#Beacon-chain-sync
# TODO: implement this:
#
# 1. Specify a large set of trusted state signees
# (perhaps stored in a config file)
#
# 2. Download a signed state hash from a known location
# (The known location can be either a HTTPS host or a DHT record)
#
# 3. Check that enough of the specified required signatures are present
#
# 4. Download a snapshot file from a known location
# (or just obtain it from the network using the ETH protocols)
#
# 5. Check that the state snapshot hash is correct and save it in the DB.
doAssert(false, "Not implemented")
proc createStateSnapshot*(
validatorDir: string, numValidators, firstValidator, genesisOffset: int,
outFile: string) =
var deposits: seq[Deposit]
for i in firstValidator..<numValidators:
deposits.add Json.loadFile(validatorDir / &"v{i:07}.deposit.json", Deposit)
let initialState = get_genesis_beacon_state(
deposits,
uint64(int(fastEpochTime() div 1000) + genesisOffset),
Eth1Data(), {})
var vr: Validator
Json.saveFile(outFile, initialState, pretty = true)
echo "Wrote ", outFile