nimbus-eth2/beacon_chain/rpc/rest_utils.nim
Jacek Sieka f70ff38b53
enable styleCheck:usages (#3573)
Some upstream repos still need fixes, but this gets us close enough that
style hints can be enabled by default.

In general, "canonical" spellings are preferred even if they violate
nep-1 - this applies in particular to spec-related stuff like
`genesis_validators_root` which appears throughout the codebase.
2022-04-08 16:22:49 +00:00

269 lines
9.3 KiB
Nim

import std/[options, macros],
stew/byteutils, presto,
../spec/[forks],
../spec/eth2_apis/[rest_types, eth2_rest_serialization],
../beacon_node,
../validators/validator_duties,
../consensus_object_pools/blockchain_dag,
"."/[rest_constants, state_ttl_cache]
export
options, eth2_rest_serialization, blockchain_dag, presto, rest_types,
rest_constants
type
ValidatorIndexError* {.pure.} = enum
UnsupportedValue, TooHighValue
func match(data: openArray[char], charset: set[char]): int =
for ch in data:
if ch notin charset:
return 1
0
proc validate(key: string, value: string): int =
## This is rough validation procedure which should be simple and fast,
## because it will be used for query routing.
case key
of "{epoch}":
0
of "{slot}":
0
of "{peer_id}":
0
of "{state_id}":
0
of "{block_id}":
0
of "{validator_id}":
0
else:
1
proc getSyncedHead*(node: BeaconNode, slot: Slot): Result[BlockRef, cstring] =
let head = node.dag.head
if slot > head.slot and not node.isSynced(head):
return err("Requesting way ahead of the current head")
ok(head)
proc getSyncedHead*(node: BeaconNode,
epoch: Epoch): Result[BlockRef, cstring] =
if epoch > MaxEpoch:
return err("Requesting epoch for which slot would overflow")
node.getSyncedHead(epoch.start_slot())
proc getBlockSlotId*(node: BeaconNode,
stateIdent: StateIdent): Result[BlockSlotId, cstring] =
case stateIdent.kind
of StateQueryKind.Slot:
# Limit requests by state id to the next epoch with respect to the current
# head to avoid long empty slot replays (in particular a second epoch
# transition)
if stateIdent.slot.epoch > (node.dag.head.slot.epoch + 1):
return err("Requesting state too far ahead of current head")
let bsi = node.dag.getBlockIdAtSlot(stateIdent.slot).valueOr:
return err("State for given slot not found, history not available?")
ok(bsi)
of StateQueryKind.Root:
if stateIdent.root == getStateRoot(node.dag.headState):
ok(node.dag.head.bid.atSlot())
else:
# We don't have a state root -> BlockSlot mapping
err("State for given root not found")
of StateQueryKind.Named:
case stateIdent.value
of StateIdentType.Head:
ok(node.dag.head.bid.atSlot())
of StateIdentType.Genesis:
ok(node.dag.genesis.atSlot())
of StateIdentType.Finalized:
ok(node.dag.finalizedHead.toBlockSlotId().expect("not nil"))
of StateIdentType.Justified:
# Take checkpoint-synced nodes into account
let justifiedEpoch =
max(
getStateField(node.dag.headState, current_justified_checkpoint).epoch,
node.dag.finalizedHead.slot.epoch)
ok(node.dag.head.atEpochStart(justifiedEpoch).toBlockSlotId().expect("not nil"))
proc getBlockId*(node: BeaconNode, id: BlockIdent): Opt[BlockId] =
case id.kind
of BlockQueryKind.Named:
case id.value
of BlockIdentType.Head:
ok(node.dag.head.bid)
of BlockIdentType.Genesis:
ok(node.dag.genesis)
of BlockIdentType.Finalized:
ok(node.dag.finalizedHead.blck.bid)
of BlockQueryKind.Root:
node.dag.getBlockId(id.root)
of BlockQueryKind.Slot:
let bsid = node.dag.getBlockIdAtSlot(id.slot)
if bsid.isSome and bsid.get().isProposed():
ok bsid.get().bid
else:
err()
proc getForkedBlock*(node: BeaconNode, id: BlockIdent):
Opt[ForkedTrustedSignedBeaconBlock] =
let bid = ? node.getBlockId(id)
node.dag.getForkedBlock(bid)
proc disallowInterruptionsAux(body: NimNode) =
for n in body:
const because =
"because the `state` variable may be mutated (and thus invalidated) " &
"before the function resumes execution."
if n.kind == nnkYieldStmt:
macros.error "You cannot use yield in this block " & because, n
if (n.kind in {nnkCall, nnkCommand} and
n[0].kind in {nnkIdent, nnkSym} and
$n[0] == "await"):
macros.error "You cannot use await in this block " & because, n
disallowInterruptionsAux(n)
macro disallowInterruptions(body: untyped) =
disallowInterruptionsAux(body)
template withStateForBlockSlotId*(nodeParam: BeaconNode,
blockSlotIdParam: BlockSlotId,
body: untyped): untyped =
block:
let
node = nodeParam
blockSlotId = blockSlotIdParam
template isState(state: ForkedHashedBeaconState): bool =
state.matches_block_slot(blockSlotId.bid.root, blockSlotId.slot)
var cache {.inject, used.}: StateCache
# If we have a cache hit, there is a concern that the REST request
# handler may continue executing asynchronously while we hit the same
# advanced state is another request. We don't want the two requests
# to work over the same state object because mutations to it will be
# visible in both, so we must outlaw yielding within the `body` block.
# Please note that the problem is not limited to the situations where
# we have a cache hit. Working with the `headState` will result in the
# same problem as it may change while the request is executing.
#
# TODO
# The solution below is only partion, because it theory yields or awaits
# can still be hidden in the body through the use of helper templates
disallowInterruptions(body)
# TODO view-types
# Avoid the code bloat produced by the double `body` reference through a lent var
if isState(node.dag.headState):
template state: untyped {.inject, used.} = node.dag.headState
template stateRoot: untyped {.inject, used.} =
getStateRoot(node.dag.headState)
body
else:
let cachedState = if node.stateTtlCache != nil:
node.stateTtlCache.getClosestState(node.dag, blockSlotId)
else:
nil
let stateToAdvance = if cachedState != nil:
cachedState
else:
assignClone(node.dag.headState)
if node.dag.updateState(stateToAdvance[], blockSlotId, false, cache):
if cachedState == nil and node.stateTtlCache != nil:
# This was not a cached state, we can cache it now
node.stateTtlCache.add(stateToAdvance)
template state: untyped {.inject, used.} = stateToAdvance[]
template stateRoot: untyped {.inject, used.} = getStateRoot(stateToAdvance[])
body
template strData*(body: ContentBody): string =
bind fromBytes
string.fromBytes(body.data)
proc toValidatorIndex*(value: RestValidatorIndex): Result[ValidatorIndex,
ValidatorIndexError] =
when sizeof(ValidatorIndex) == 4:
if uint64(value) < VALIDATOR_REGISTRY_LIMIT:
# On x86 platform Nim allows only `int32` indexes, so all the indexes in
# range `2^31 <= x < 2^32` are not supported.
if uint64(value) <= uint64(high(int32)):
ok(ValidatorIndex(value))
else:
err(ValidatorIndexError.UnsupportedValue)
else:
err(ValidatorIndexError.TooHighValue)
elif sizeof(ValidatorIndex) == 8:
if uint64(value) < VALIDATOR_REGISTRY_LIMIT:
ok(ValidatorIndex(value))
else:
err(ValidatorIndexError.TooHighValue)
else:
doAssert(false, "ValidatorIndex type size is incorrect")
func syncCommitteeParticipants*(forkedState: ForkedHashedBeaconState,
epoch: Epoch
): Result[seq[ValidatorPubKey], cstring] =
withState(forkedState):
when stateFork >= BeaconStateFork.Altair:
let
epochPeriod = sync_committee_period(epoch)
curPeriod = sync_committee_period(state.data.slot)
if epochPeriod == curPeriod:
ok(@(state.data.current_sync_committee.pubkeys.data))
elif epochPeriod == curPeriod + 1:
ok(@(state.data.next_sync_committee.pubkeys.data))
else:
err("Epoch is outside the sync committee period of the state")
else:
err("State's fork do not support sync committees")
func keysToIndices*(cacheTable: var Table[ValidatorPubKey, ValidatorIndex],
forkedState: ForkedHashedBeaconState,
keys: openArray[ValidatorPubKey]
): seq[Option[ValidatorIndex]] =
var indices = newSeq[Option[ValidatorIndex]](len(keys))
let totalValidatorsInState = getStateField(forkedState, validators).lenu64
var keyset =
block:
var res: Table[ValidatorPubKey, int]
for inputIndex, pubkey in keys.pairs():
# Try to search in cache first.
cacheTable.withValue(pubkey, vindex):
if uint64(vindex[]) < totalValidatorsInState:
indices[inputIndex] = some(vindex[])
do:
res[pubkey] = inputIndex
res
if len(keyset) > 0:
for validatorIndex, validator in getStateField(forkedState,
validators).pairs():
keyset.withValue(validator.pubkey, listIndex):
# Store pair (pubkey, index) into cache table.
cacheTable[validator.pubkey] = ValidatorIndex(validatorIndex)
# Fill result sequence.
indices[listIndex[]] = some(ValidatorIndex(validatorIndex))
indices
proc getRouter*(allowedOrigin: Option[string]): RestRouter =
RestRouter.init(validate, allowedOrigin = allowedOrigin)
const
jsonMediaType* = MediaType.init("application/json")
sszMediaType* = MediaType.init("application/octet-stream")
textEventStreamMediaType* = MediaType.init("text/event-stream")