nim-dagger/codex/blockexchange/engine/pendingblocks.nim

109 lines
2.7 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 pkg/upraises
push: {.upraises: [].}
import pkg/chronicles
import pkg/chronos
import pkg/libp2p
import ../../blocktype
logScope:
topics = "codex pendingblocks"
const
DefaultBlockTimeout* = 10.minutes
type
BlockReq* = object
handle*: Future[Block]
inFlight*: bool
PendingBlocksManager* = ref object of RootObj
blocks*: Table[Cid, BlockReq] # pending Block requests
proc getWantHandle*(
p: PendingBlocksManager,
cid: Cid,
timeout = DefaultBlockTimeout,
inFlight = false
): Future[Block] {.async.} =
## Add an event for a block
##
try:
if cid notin p.blocks:
p.blocks[cid] = BlockReq(
handle: newFuture[Block]("pendingBlocks.getWantHandle"),
inFlight: inFlight)
trace "Adding pending future for block", cid, inFlight = p.blocks[cid].inFlight
return await p.blocks[cid].handle.wait(timeout)
except CancelledError as exc:
trace "Blocks cancelled", exc = exc.msg, cid
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(cid)
proc resolve*(p: PendingBlocksManager,
blocks: seq[Block]) =
## Resolve pending blocks
##
for blk in blocks:
# resolve any pending blocks
p.blocks.withValue(blk.cid, pending):
if not pending[].handle.completed:
trace "Resolving block", cid = blk.cid
pending[].handle.complete(blk)
proc setInFlight*(p: PendingBlocksManager,
cid: Cid,
inFlight = true) =
p.blocks.withValue(cid, pending):
pending[].inFlight = inFlight
trace "Setting inflight", cid, inFlight = pending[].inFlight
proc isInFlight*(p: PendingBlocksManager,
cid: Cid
): 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 =
p.pending(cid)
iterator wantList*(p: PendingBlocksManager): Cid =
for k in p.blocks.keys:
yield k
iterator wantHandles*(p: PendingBlocksManager): Future[Block] =
for v in p.blocks.values:
yield v.handle
func len*(p: PendingBlocksManager): int =
p.blocks.len
func new*(T: type PendingBlocksManager): PendingBlocksManager =
PendingBlocksManager()