348 lines
11 KiB
Nim

## Nim-Codex
## Copyright (c) 2021 Status Research & Development GmbH
## Licensed under either of
## * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
## * MIT license ([LICENSE-MIT](LICENSE-MIT))
## at your option.
## This file may not be copied, modified, or distributed except according to
## those terms.
import std/tables
import std/monotimes
import pkg/upraises
push: {.upraises: [].}
import ../../blocktype
import pkg/chronicles
import pkg/questionable
import pkg/questionable/options
import pkg/questionable/results
import pkg/chronos
import pkg/libp2p
import pkg/metrics
import pkg/questionable/results
import ../protobuf/blockexc
import ../../merkletree
import ../../utils
logScope:
topics = "codex pendingblocks"
declareGauge(codex_block_exchange_pending_block_requests, "codex blockexchange pending block requests")
declareGauge(codex_block_exchange_retrieval_time_us, "codex blockexchange block retrieval time us")
const
DefaultBlockTimeout* = 10.minutes
type
BlockReq* = object
handle*: Future[Block]
inFlight*: bool
startTime*: int64
LeafReq* = object
case delivered*: bool
of false:
handle*: Future[Block]
inFlight*: bool
of true:
leaf: MultiHash
blkCid*: Cid
TreeReq* = ref object
leaves*: Table[Natural, LeafReq]
deliveredCount*: Natural
leavesCount*: ?Natural
treeRoot*: MultiHash
treeCid*: Cid
TreeHandler* = proc(tree: MerkleTree): Future[void] {.gcsafe.}
PendingBlocksManager* = ref object of RootObj
blocks*: Table[Cid, BlockReq] # pending Block requests
trees*: Table[Cid, TreeReq]
onTree*: TreeHandler
proc updatePendingBlockGauge(p: PendingBlocksManager) =
codex_block_exchange_pending_block_requests.set(p.blocks.len.int64)
type
BlockHandleOrCid = object
case resolved*: bool
of true:
cid*: Cid
else:
handle*: Future[Block]
proc buildTree(treeReq: TreeReq): ?!MerkleTree =
trace "Building a merkle tree from leaves", treeCid = treeReq.treeCid, leavesCount = treeReq.leavesCount
without leavesCount =? treeReq.leavesCount:
return failure("Leaves count is none, cannot build a tree")
var builder = ? MerkleTreeBuilder.init(treeReq.treeRoot.mcodec)
for i in 0..<leavesCount:
treeReq.leaves.withValue(i, leafReq):
if leafReq.delivered:
? builder.addLeaf(leafReq.leaf)
else:
return failure("Expected all leaves to be delivered but leaf with index " & $i & " was not")
do:
return failure("Missing a leaf with index " & $i)
let tree = ? builder.build()
if tree.root != treeReq.treeRoot:
return failure("Reconstructed tree root doesn't match the original tree root, tree cid is " & $treeReq.treeCid)
return success(tree)
proc checkIfAllDelivered(p: PendingBlocksManager, treeReq: TreeReq): void =
if treeReq.deliveredCount.some == treeReq.leavesCount:
without tree =? buildTree(treeReq), err:
error "Error building a tree", msg = err.msg
p.trees.del(treeReq.treeCid)
return
p.trees.del(treeReq.treeCid)
try:
asyncSpawn p.onTree(tree)
except Exception as err:
error "Exception when handling tree", msg = err.msg
proc getWantHandleOrCid*(
treeReq: TreeReq,
index: Natural,
timeout = DefaultBlockTimeout
): BlockHandleOrCid =
treeReq.leaves.withValue(index, leafReq):
if not leafReq.delivered:
return BlockHandleOrCid(resolved: false, handle: leafReq.handle)
else:
return BlockHandleOrCid(resolved: true, cid: leafReq.blkCid)
do:
let leafReq = LeafReq(
delivered: false,
handle: newFuture[Block]("pendingBlocks.getWantHandleOrCid"),
inFlight: false
)
treeReq.leaves[index] = leafReq
return BlockHandleOrCid(resolved: false, handle: leafReq.handle)
proc getOrPutTreeReq*(
p: PendingBlocksManager,
treeCid: Cid,
leavesCount = Natural.none, # has value when all leaves are expected to be delivered
treeRoot: MultiHash
): ?!TreeReq =
p.trees.withValue(treeCid, treeReq):
if treeReq.treeRoot != treeRoot:
return failure("Unexpected root for tree with cid " & $treeCid)
if leavesCount == treeReq.leavesCount:
return success(treeReq[])
else:
treeReq.leavesCount = treeReq.leavesCount.orElse(leavesCount)
let res = success(treeReq[])
p.checkIfAllDelivered(treeReq[])
return res
do:
let treeReq = TreeReq(
deliveredCount: 0,
leavesCount: leavesCount,
treeRoot: treeRoot,
treeCid: treeCid
)
p.trees[treeCid] = treeReq
return success(treeReq)
proc getWantHandle*(
p: PendingBlocksManager,
address: BlockAddress,
timeout = DefaultBlockTimeout,
inFlight = false
): Future[Block] {.async.} =
## Add an event for a block
##
try:
if address notin p.blocks:
p.blocks[address] = BlockReq(
handle: newFuture[Block]("pendingBlocks.getWantHandle"),
inFlight: inFlight,
startTime: getMonoTime().ticks)
trace "Adding pending future for block", address, inFlight = p.blocks[address].inFlight
p.updatePendingBlockGauge()
return await p.blocks[address].handle.wait(timeout)
except CancelledError as exc:
trace "Blocks cancelled", exc = exc.msg, address
raise exc
except CatchableError as exc:
trace "Pending WANT failed or expired", exc = exc.msg
# no need to cancel, it is already cancelled by wait()
raise exc
finally:
p.blocks.del(address)
p.updatePendingBlockGauge()
proc getOrComputeLeaf(mcodec: MultiCodec, blk: Block): ?!MultiHash =
without mhash =? blk.cid.mhash.mapFailure, err:
return MultiHash.digest($mcodec, blk.data).mapFailure
if mhash.mcodec == mcodec:
return success(mhash)
else:
return MultiHash.digest($mcodec, blk.data).mapFailure
proc resolve*(
p: PendingBlocksManager,
blocksDelivery: seq[BlockDelivery]
) {.gcsafe, raises: [].} =
## Resolve pending blocks
##
for bd in blocksDelivery:
if not bd.address.leaf:
if bd.address.cid == bd.blk.cid:
p.blocks.withValue(bd.blk.cid, pending):
if not pending.handle.completed:
trace "Resolving block", cid = bd.blk.cid
pending.handle.complete(bd.blk)
let
startTime = pending[].startTime
stopTime = getMonoTime().ticks
retrievalDurationUs = (stopTime - startTime) div 1000
codexBlockExchangeRetrievalTimeUs.set(retrievalDurationUs)
trace "Block retrieval time", retrievalDurationUs
else:
warn "Delivery cid doesn't match block cid", deliveryCid = bd.address.cid, blockCid = bd.blk.cid
# resolve any pending blocks
if bd.address.leaf:
p.trees.withValue(bd.address.treeCid, treeReq):
treeReq.leaves.withValue(bd.address.index, leafReq):
if not leafReq.delivered:
if proof =? bd.proof:
if not proof.index == bd.address.index:
warn "Proof index doesn't match leaf index", address = bd.address, proofIndex = proof.index
continue
without mhash =? bd.blk.cid.mhash.mapFailure, err:
error "Unable to get mhash from cid for block", address = bd.address, msg = err.msg
continue
without verifySuccess =? proof.verifyLeaf(mhash, treeReq.treeRoot), err:
error "Unable to verify proof for block", address = bd.address, msg = err.msg
continue
if verifySuccess:
without leaf =? getOrComputeLeaf(treeReq.treeRoot.mcodec, bd.blk), err:
error "Unable to get or calculate hash for block", address = bd.address
continue
leafReq.handle.complete(bd.blk)
leafReq[] = LeafReq(delivered: true, blkCid: bd.blk.cid, leaf: leaf)
inc treeReq.deliveredCount
p.checkIfAllDelivered(treeReq[])
else:
warn "Invalid proof provided for a block", address = bd.address
else:
warn "Missing proof for a block", address = bd.address
else:
trace "Ignore veryfing proof for already delivered block", address = bd.address
proc setInFlight*(p: PendingBlocksManager,
address: BlockAddress,
inFlight = true) =
p.blocks.withValue(cid, pending):
pending.inFlight = inFlight
trace "Setting inflight", cid, inFlight = pending.inFlight
proc trySetInFlight*(treeReq: TreeReq,
index: Natural,
inFlight = true) =
treeReq.leaves.withValue(index, leafReq):
if not leafReq.delivered:
leafReq.inFlight = inFlight
trace "Setting inflight", treeCid = treeReq.treeCid, index, inFlight = inFlight
proc isInFlight*(treeReq: TreeReq,
index: Natural
): bool =
treeReq.leaves.withValue(index, leafReq):
return (not leafReq.delivered) and leafReq.inFlight
do:
return false
proc isInFlight*(p: PendingBlocksManager,
address: BlockAddress,
): bool =
p.blocks.withValue(cid, pending):
result = pending.inFlight
trace "Getting inflight", cid, inFlight = result
proc pending*(p: PendingBlocksManager, cid: Cid): bool =
cid in p.blocks
proc contains*(p: PendingBlocksManager, cid: Cid): bool =
BlockAddress.init(cid) in p.blocks
proc contains*(p: PendingBlocksManager, address: BlockAddress): bool =
address in p.blocks
iterator wantList*(p: PendingBlocksManager): BlockAddress =
for a in p.blocks.keys:
yield a
iterator wantListBlockCids*(p: PendingBlocksManager): Cid =
for a in p.blocks.keys:
if not a.leaf:
yield a.cid
iterator wantListCids*(p: PendingBlocksManager): Cid =
var yieldedCids = initHashSet[Cid]()
for a in p.blocks.keys:
let cid = a.cidOrTreeCid
if cid notin yieldedCids:
yieldedCids.incl(cid)
yield cid
iterator wantList*(p: PendingBlocksManager): BlockAddress =
for k in p.blocks.keys:
yield BlockAddress(leaf: false, cid: k)
for treeCid, treeReq in p.trees.pairs:
for index, leafReq in treeReq.leaves.pairs:
if not leafReq.delivered:
yield BlockAddress(leaf: true, treeCid: treeCid, index: index)
iterator wantListBlockCids*(p: PendingBlocksManager): Cid =
for k in p.blocks.keys:
yield k
iterator wantListCids*(p: PendingBlocksManager): Cid =
for k in p.blocks.keys:
yield k
for k in p.trees.keys:
yield k
iterator wantHandles*(p: PendingBlocksManager): Future[Block] =
for v in p.blocks.values:
yield v.handle
proc wantListLen*(p: PendingBlocksManager): int =
p.blocks.len + p.trees.len
func len*(p: PendingBlocksManager): int =
p.blocks.len
func new*(T: type PendingBlocksManager): PendingBlocksManager =
PendingBlocksManager()