nimbus-eth2/beacon_chain/request_manager.nim

72 lines
2.4 KiB
Nim

import
options, random,
chronos, chronicles,
spec/datatypes,
eth2_network, beacon_node_types, sync_protocol,
eth/async_utils
type
RequestManager* = object
network*: Eth2Node
proc init*(T: type RequestManager, network: Eth2Node): T =
T(network: network)
type
FetchAncestorsResponseHandler = proc (b: SignedBeaconBlock) {.gcsafe.}
proc fetchAncestorBlocksFromPeer(
peer: Peer,
rec: FetchRecord,
responseHandler: FetchAncestorsResponseHandler) {.async.} =
# TODO: It's not clear if this function follows the intention of the
# FetchRecord data type. Perhaps it is supposed to get a range of blocks
# instead. In order to do this, we'll need the slot number of the known
# block to be stored in the FetchRecord, so we can ask for a range of
# blocks starting N positions before this slot number.
try:
let blocks = await peer.beaconBlocksByRoot([rec.root])
if blocks.isOk:
for b in blocks.get:
responseHandler(b)
except CatchableError as err:
debug "Error while fetching ancestor blocks",
err = err.msg, root = rec.root, peer = peer
proc fetchAncestorBlocksFromNetwork(
network: Eth2Node,
rec: FetchRecord,
responseHandler: FetchAncestorsResponseHandler) {.async.} =
var peer: Peer
try:
peer = await network.peerPool.acquire()
let blocks = await peer.beaconBlocksByRoot([rec.root])
if blocks.isOk:
for b in blocks.get:
responseHandler(b)
except CatchableError as err:
debug "Error while fetching ancestor blocks",
err = err.msg, root = rec.root, peer = peer
finally:
if not(isNil(peer)):
network.peerPool.release(peer)
proc fetchAncestorBlocks*(requestManager: RequestManager,
roots: seq[FetchRecord],
responseHandler: FetchAncestorsResponseHandler) =
# TODO: we could have some fancier logic here:
#
# * Keeps track of what was requested
# (this would give a little bit of time for the asked peer to respond)
#
# * Keep track of the average latency of each peer
# (we can give priority to peers with better latency)
#
const ParallelRequests = 2
for i in 0 ..< ParallelRequests:
traceAsyncErrors fetchAncestorBlocksFromNetwork(requestManager.network,
roots.sample(),
responseHandler)