nimbus-eth2/beacon_chain/beacon_chain_db.nim

499 lines
18 KiB
Nim

{.push raises: [Defect].}
import
typetraits, tables,
stew/[results, objects, endians2, io2],
serialization, chronicles, snappy,
eth/db/[kvstore, kvstore_sqlite3],
./network_metadata,
./spec/[datatypes, digest, crypto, state_transition],
./ssz/[ssz_serialization, merkleization],
merkle_minimal, filepath
type
DbSeq*[T] = object
insertStmt: SqliteStmt[openArray[byte], void]
selectStmt: SqliteStmt[int64, openArray[byte]]
recordCount: int64
DbMap*[K, V] = object
db: SqStoreRef
keyspace: int
DepositsSeq = DbSeq[DepositData]
DepositsMerkleizer* = SszMerkleizer[depositContractLimit]
DepositContractSnapshot* = object
eth1Block*: Eth2Digest
depositContractState*: DepositContractState
BeaconChainDB* = ref object
## Database storing resolved blocks and states - resolved blocks are such
## blocks that form a chain back to the tail block.
##
## We assume that the database backend is working / not corrupt - as such,
## we will raise a Defect any time there is an issue. This should be
## revisited in the future, when/if the calling code safely can handle
## corruption of this kind.
##
## We do however make an effort not to crash on invalid data inside the
## database - this may have a number of "natural" causes such as switching
## between different versions of the client and accidentally using an old
## database.
backend: KvStoreRef
preset: RuntimePreset
genesisDeposits*: DepositsSeq
checkpoint*: proc() {.gcsafe.}
Keyspaces* = enum
defaultKeyspace = "kvstore"
validatorIndexFromPubKey
DbKeyKind = enum
kHashToState
kHashToBlock
kHeadBlock
## Pointer to the most recent block selected by the fork choice
kTailBlock
## Pointer to the earliest finalized block - this is the genesis block when
## the chain starts, but might advance as the database gets pruned
## TODO: determine how aggressively the database should be pruned. For a
## healthy network sync, we probably need to store blocks at least
## past the weak subjectivity period.
kBlockSlotStateRoot
## BlockSlot -> state_root mapping
kGenesisBlockRoot
## Immutable reference to the network genesis state
## (needed for satisfying requests to the beacon node API).
kEth1PersistedTo
## (Obsolete) Used to point to the the latest ETH1 block hash which
## satisfied the follow distance and had its deposits persisted to disk.
kDepositsFinalizedByEth1
## A merkleizer checkpoint which can be used for computing the
## `deposit_root` of all eth1 finalized deposits (i.e. deposits
## confirmed by ETH1_FOLLOW_DISTANCE blocks). The `deposit_root`
## is acknowledged and confirmed by the attached web3 provider.
kDepositsFinalizedByEth2
## A merkleizer checkpoint used for computing merkle proofs of
## deposits added to Eth2 blocks (it may lag behind the finalized
## eth1 deposits checkpoint).
kHashToBlockSummary
## Cache of beacon block summaries - during startup when we construct the
## chain dag, loading full blocks takes a lot of time - the block
## summary contains a minimal snapshot of what's needed to instanciate
## the BlockRef tree.
kSpeculativeDeposits
## A merkelizer checkpoint created on the basis of deposit events
## that we were not able to verify against a `deposit_root` served
## by the web3 provider. This may happen on Geth nodes that serve
## only recent contract state data (i.e. only recent `deposit_roots`).
kHashToStateDiff
## Instead of storing full BeaconStates, one can store only the diff from
## a different state. As 75% of a typical BeaconState's serialized form's
## the validators, which are mostly immutable and append-only, just using
## a simple append-diff representation helps significantly. Various roots
## are stored in a mod-increment pattern across fixed-sized arrays, which
## addresses most of the rest of the BeaconState sizes.
BeaconBlockSummary* = object
slot*: Slot
parent_root*: Eth2Digest
const
# The largest object we're saving is the BeaconState, and by far, the largest
# part of it is the validator - each validator takes up at least 129 bytes
# in phase0, which means 100k validators is >12mb - in addition to this,
# there are several MB of hashes.
maxDecompressedDbRecordSize = 64*1024*1024
# Subkeys essentially create "tables" within the key-value store by prefixing
# each entry with a table id
func subkey(kind: DbKeyKind): array[1, byte] =
result[0] = byte ord(kind)
func subkey[N: static int](kind: DbKeyKind, key: array[N, byte]):
array[N + 1, byte] =
result[0] = byte ord(kind)
result[1 .. ^1] = key
func subkey(kind: type BeaconState, key: Eth2Digest): auto =
subkey(kHashToState, key.data)
func subkey(kind: type SignedBeaconBlock, key: Eth2Digest): auto =
subkey(kHashToBlock, key.data)
func subkey(kind: type BeaconBlockSummary, key: Eth2Digest): auto =
subkey(kHashToBlockSummary, key.data)
func subkey(kind: type BeaconStateDiff, key: Eth2Digest): auto =
subkey(kHashToStateDiff, key.data)
func subkey(root: Eth2Digest, slot: Slot): array[40, byte] =
var ret: array[40, byte]
# big endian to get a naturally ascending order on slots in sorted indices
ret[0..<8] = toBytesBE(slot.uint64)
# .. but 7 bytes should be enough for slots - in return, we get a nicely
# rounded key length
ret[0] = byte ord(kBlockSlotStateRoot)
ret[8..<40] = root.data
ret
template panic =
# TODO(zah): Could we recover from a corrupted database?
# Review all usages.
raiseAssert "The database should not be corrupted"
proc init*[T](Seq: type DbSeq[T], db: SqStoreRef, name: string): Seq =
db.exec("""
CREATE TABLE IF NOT EXISTS """ & name & """(
id INTEGER PRIMARY KEY,
value BLOB
);
""").expect "working database"
let
insertStmt = db.prepareStmt(
"INSERT INTO " & name & "(value) VALUES (?);",
openArray[byte], void).expect("this is a valid statement")
selectStmt = db.prepareStmt(
"SELECT value FROM " & name & " WHERE id = ?;",
int64, openArray[byte]).expect("this is a valid statement")
countStmt = db.prepareStmt(
"SELECT COUNT(1) FROM " & name & ";",
NoParams, int64).expect("this is a valid statement")
var recordCount = int64 0
let countQueryRes = countStmt.exec do (res: int64):
recordCount = res
let found = countQueryRes.expect("working database")
if not found: panic()
Seq(insertStmt: insertStmt,
selectStmt: selectStmt,
recordCount: recordCount)
proc add*[T](s: var DbSeq[T], val: T) =
var bytes = SSZ.encode(val)
s.insertStmt.exec(bytes).expect "working database"
inc s.recordCount
template len*[T](s: DbSeq[T]): uint64 =
s.recordCount.uint64
proc get*[T](s: DbSeq[T], idx: uint64): T =
# This is used only locally
let resultAddr = addr result
let queryRes = s.selectStmt.exec(int64(idx) + 1) do (recordBytes: openArray[byte]):
try:
resultAddr[] = decode(SSZ, recordBytes, T)
except SerializationError:
panic()
let found = queryRes.expect("working database")
if not found: panic()
proc createMap*(db: SqStoreRef, keyspace: int;
K, V: distinct type): DbMap[K, V] =
DbMap[K, V](db: db, keyspace: keyspace)
proc insert*[K, V](m: var DbMap[K, V], key: K, value: V) =
m.db.put(m.keyspace, SSZ.encode key, SSZ.encode value).expect("working database")
proc contains*[K, V](m: DbMap[K, V], key: K): bool =
contains(m.db, SSZ.encode key).expect("working database")
template insert*[K, V](t: var Table[K, V], key: K, value: V) =
add(t, key, value)
proc init*(T: type BeaconChainDB,
preset: RuntimePreset,
dir: string,
inMemory = false): BeaconChainDB =
if inMemory:
# TODO
# To support testing, the inMemory store should offer the complete
# functionalityof the database-backed one (i.e. tracking of deposits
# and validators)
T(backend: kvStore MemStoreRef.init(),
preset: preset)
else:
let s = secureCreatePath(dir)
doAssert s.isOk # TODO(zah) Handle this in a better way
let sqliteStore = SqStoreRef.init(
dir, "nbc", Keyspaces, manualCheckpoint = true).expect("working database")
# Remove the deposits table we used before we switched
# to storing only deposit contract checkpoints
if sqliteStore.exec("DROP TABLE IF EXISTS deposits;").isErr:
debug "Failed to drop the deposits table"
var
validatorKeyToIndex = initTable[ValidatorPubKey, ValidatorIndex]()
genesisDepositsSeq = DbSeq[DepositData].init(sqliteStore, "genesis_deposits")
T(backend: kvStore sqliteStore,
preset: preset,
genesisDeposits: genesisDepositsSeq,
checkpoint: proc() = sqliteStore.checkpoint()
)
proc snappyEncode(inp: openArray[byte]): seq[byte] =
try:
snappy.encode(inp)
except CatchableError as err:
raiseAssert err.msg
proc put(db: BeaconChainDB, key: openArray[byte], v: Eth2Digest) =
db.backend.put(key, v.data).expect("working database")
proc put(db: BeaconChainDB, key: openArray[byte], v: auto) =
db.backend.put(key, snappyEncode(SSZ.encode(v))).expect("working database")
proc get(db: BeaconChainDB, key: openArray[byte], T: type Eth2Digest): Opt[T] =
var res: Opt[T]
proc decode(data: openArray[byte]) =
if data.len == 32:
res.ok Eth2Digest(data: toArray(32, data))
else:
# If the data can't be deserialized, it could be because it's from a
# version of the software that uses a different SSZ encoding
warn "Unable to deserialize data, old database?",
typ = name(T), dataLen = data.len
discard
discard db.backend.get(key, decode).expect("working database")
res
type GetResult = enum
found = "Found"
notFound = "Not found"
corrupted = "Corrupted"
proc get[T](db: BeaconChainDB, key: openArray[byte], output: var T): GetResult =
var status = GetResult.notFound
# TODO address is needed because there's no way to express lifetimes in nim
# we'll use unsafeAddr to find the code later
var outputPtr = unsafeAddr output # callback is local, ptr wont escape
proc decode(data: openArray[byte]) =
try:
let decompressed = snappy.decode(data, maxDecompressedDbRecordSize)
if decompressed.len > 0:
outputPtr[] = SSZ.decode(decompressed, T, updateRoot = false)
status = GetResult.found
else:
warn "Corrupt snappy record found in database", typ = name(T)
status = GetResult.corrupted
except SerializationError as e:
# If the data can't be deserialized, it could be because it's from a
# version of the software that uses a different SSZ encoding
warn "Unable to deserialize data, old database?",
err = e.msg, typ = name(T), dataLen = data.len
status = GetResult.corrupted
discard db.backend.get(key, decode).expect("working database")
status
proc close*(db: BeaconChainDB) =
discard db.backend.close()
func toBeaconBlockSummary(v: SomeBeaconBlock): BeaconBlockSummary =
BeaconBlockSummary(
slot: v.slot,
parent_root: v.parent_root,
)
proc putBlock*(db: BeaconChainDB, value: SignedBeaconBlock) =
db.put(subkey(type value, value.root), value)
db.put(subkey(BeaconBlockSummary, value.root), value.message.toBeaconBlockSummary())
proc putBlock*(db: BeaconChainDB, value: TrustedSignedBeaconBlock) =
db.put(subkey(SignedBeaconBlock, value.root), value)
db.put(subkey(BeaconBlockSummary, value.root), value.message.toBeaconBlockSummary())
proc putState*(db: BeaconChainDB, key: Eth2Digest, value: BeaconState) =
# TODO prune old states - this is less easy than it seems as we never know
# when or if a particular state will become finalized.
db.put(subkey(type value, key), value)
proc putState*(db: BeaconChainDB, value: BeaconState) =
db.putState(hash_tree_root(value), value)
proc putStateRoot*(db: BeaconChainDB, root: Eth2Digest, slot: Slot,
value: Eth2Digest) =
db.put(subkey(root, slot), value)
proc putStateDiff*(db: BeaconChainDB, root: Eth2Digest, value: BeaconStateDiff) =
db.put(subkey(BeaconStateDiff, root), value)
proc delBlock*(db: BeaconChainDB, key: Eth2Digest) =
db.backend.del(subkey(SignedBeaconBlock, key)).expect("working database")
db.backend.del(subkey(BeaconBlockSummary, key)).expect("working database")
proc delState*(db: BeaconChainDB, key: Eth2Digest) =
db.backend.del(subkey(BeaconState, key)).expect("working database")
proc delStateRoot*(db: BeaconChainDB, root: Eth2Digest, slot: Slot) =
db.backend.del(subkey(root, slot)).expect("working database")
proc delStateDiff*(db: BeaconChainDB, root: Eth2Digest) =
db.backend.del(subkey(BeaconStateDiff, root)).expect("working database")
proc putHeadBlock*(db: BeaconChainDB, key: Eth2Digest) =
db.put(subkey(kHeadBlock), key)
proc putTailBlock*(db: BeaconChainDB, key: Eth2Digest) =
db.put(subkey(kTailBlock), key)
proc putGenesisBlockRoot*(db: BeaconChainDB, key: Eth2Digest) =
db.put(subkey(kGenesisBlockRoot), key)
proc putEth1FinalizedTo*(db: BeaconChainDB,
eth1Checkpoint: DepositContractSnapshot) =
db.put(subkey(kDepositsFinalizedByEth1), eth1Checkpoint)
proc putEth2FinalizedTo*(db: BeaconChainDB,
eth1Checkpoint: DepositContractSnapshot) =
db.put(subkey(kDepositsFinalizedByEth2), eth1Checkpoint)
proc putSpeculativeDeposits*(db: BeaconChainDB,
eth1Checkpoint: DepositContractSnapshot) =
db.put(subkey(kSpeculativeDeposits), eth1Checkpoint)
proc getBlock*(db: BeaconChainDB, key: Eth2Digest): Opt[TrustedSignedBeaconBlock] =
# We only store blocks that we trust in the database
result.ok(TrustedSignedBeaconBlock())
if db.get(subkey(SignedBeaconBlock, key), result.get) != GetResult.found:
result.err()
else:
# set root after deserializing (so it doesn't get zeroed)
result.get().root = key
proc getBlockSummary*(db: BeaconChainDB, key: Eth2Digest): Opt[BeaconBlockSummary] =
# We only store blocks that we trust in the database
result.ok(BeaconBlockSummary())
if db.get(subkey(BeaconBlockSummary, key), result.get) != GetResult.found:
result.err()
proc getState*(
db: BeaconChainDB, key: Eth2Digest, output: var BeaconState,
rollback: RollbackProc): bool =
## Load state into `output` - BeaconState is large so we want to avoid
## re-allocating it if possible
## Return `true` iff the entry was found in the database and `output` was
## overwritten.
## Rollback will be called only if output was partially written - if it was
## not found at all, rollback will not be called
# TODO rollback is needed to deal with bug - use `noRollback` to ignore:
# https://github.com/nim-lang/Nim/issues/14126
# TODO RVO is inefficient for large objects:
# https://github.com/nim-lang/Nim/issues/13879
case db.get(subkey(BeaconState, key), output)
of GetResult.found:
true
of GetResult.notFound:
false
of GetResult.corrupted:
rollback(output)
false
proc getStateRoot*(db: BeaconChainDB,
root: Eth2Digest,
slot: Slot): Opt[Eth2Digest] =
db.get(subkey(root, slot), Eth2Digest)
proc getStateDiff*(db: BeaconChainDB,
root: Eth2Digest): Opt[BeaconStateDiff] =
result.ok(BeaconStateDiff())
if db.get(subkey(BeaconStateDiff, root), result.get) != GetResult.found:
result.err
proc getHeadBlock*(db: BeaconChainDB): Opt[Eth2Digest] =
db.get(subkey(kHeadBlock), Eth2Digest)
proc getTailBlock*(db: BeaconChainDB): Opt[Eth2Digest] =
db.get(subkey(kTailBlock), Eth2Digest)
proc getGenesisBlockRoot*(db: BeaconChainDB): Eth2Digest =
db.get(subkey(kGenesisBlockRoot), Eth2Digest).expect(
"The database must be seeded with the genesis state")
proc getEth1FinalizedTo*(db: BeaconChainDB): Opt[DepositContractSnapshot] =
result.ok(DepositContractSnapshot())
let r = db.get(subkey(kDepositsFinalizedByEth1), result.get)
if r != found: result.err()
proc getEth2FinalizedTo*(db: BeaconChainDB): Opt[DepositContractSnapshot] =
result.ok(DepositContractSnapshot())
let r = db.get(subkey(kDepositsFinalizedByEth2), result.get)
if r != found: result.err()
proc getSpeculativeDeposits*(db: BeaconChainDB): Opt[DepositContractSnapshot] =
result.ok(DepositContractSnapshot())
let r = db.get(subkey(kSpeculativeDeposits), result.get)
if r != found: result.err()
proc delSpeculativeDeposits*(db: BeaconChainDB) =
db.backend.del(subkey(kSpeculativeDeposits)).expect("working database")
proc containsBlock*(db: BeaconChainDB, key: Eth2Digest): bool =
db.backend.contains(subkey(SignedBeaconBlock, key)).expect("working database")
proc containsState*(db: BeaconChainDB, key: Eth2Digest): bool =
db.backend.contains(subkey(BeaconState, key)).expect("working database")
proc containsStateDiff*(db: BeaconChainDB, key: Eth2Digest): bool =
db.backend.contains(subkey(BeaconStateDiff, key)).expect("working database")
iterator getAncestors*(db: BeaconChainDB, root: Eth2Digest):
TrustedSignedBeaconBlock =
## Load a chain of ancestors for blck - returns a list of blocks with the
## oldest block last (blck will be at result[0]).
##
## The search will go on until the ancestor cannot be found.
var
res: TrustedSignedBeaconBlock
root = root
while db.get(subkey(SignedBeaconBlock, root), res) == GetResult.found:
res.root = root
yield res
root = res.message.parent_root
iterator getAncestorSummaries*(db: BeaconChainDB, root: Eth2Digest):
tuple[root: Eth2Digest, summary: BeaconBlockSummary] =
## Load a chain of ancestors for blck - returns a list of blocks with the
## oldest block last (blck will be at result[0]).
##
## The search will go on until the ancestor cannot be found.
var
res: tuple[root: Eth2Digest, summary: BeaconBlockSummary]
tmp: TrustedSignedBeaconBlock
root = root
while true:
if db.get(subkey(BeaconBlockSummary, root), res.summary) == GetResult.found:
res.root = root
yield res
elif db.get(subkey(SignedBeaconBlock, root), tmp) == GetResult.found:
res.summary = tmp.message.toBeaconBlockSummary()
db.put(subkey(BeaconBlockSummary, root), res.summary)
res.root = root
yield res
else:
break
root = res.summary.parent_root