nwaku/waku/v2/protocol/waku_store/protocol.nim

123 lines
3.3 KiB
Nim

## Waku Store protocol for historical messaging support.
## See spec for more details:
## https://github.com/vacp2p/specs/blob/master/specs/waku/v2/waku-store.md
when (NimMajor, NimMinor) < (1, 4):
{.push raises: [Defect].}
else:
{.push raises: [].}
import
std/options,
stew/results,
chronicles,
chronos,
bearssl/rand,
libp2p/crypto/crypto,
libp2p/protocols/protocol,
libp2p/protobuf/minprotobuf,
libp2p/stream/connection,
metrics
import
../../node/peer_manager,
../../utils/time,
./common,
./rpc,
./rpc_codec,
./protocol_metrics
logScope:
topics = "waku store"
const
MaxMessageTimestampVariance* = getNanoSecondTime(20) # 20 seconds maximum allowable sender timestamp "drift"
type HistoryQueryHandler* = proc(req: HistoryQuery): HistoryResult {.gcsafe.}
type
WakuStore* = ref object of LPProtocol
peerManager: PeerManager
rng: ref rand.HmacDrbgContext
queryHandler: HistoryQueryHandler
## Protocol
proc initProtocolHandler(ws: WakuStore) =
proc handler(conn: Connection, proto: string) {.async.} =
let buf = await conn.readLp(MaxRpcSize.int)
let decodeRes = HistoryRPC.decode(buf)
if decodeRes.isErr():
error "failed to decode rpc", peerId= $conn.peerId
waku_store_errors.inc(labelValues = [decodeRpcFailure])
# TODO: Return (BAD_REQUEST, cause: "decode rpc failed")
return
let reqRpc = decodeRes.value
if reqRpc.query.isNone():
error "empty query rpc", peerId= $conn.peerId, requestId=reqRpc.requestId
waku_store_errors.inc(labelValues = [emptyRpcQueryFailure])
# TODO: Return (BAD_REQUEST, cause: "empty query")
return
let
requestId = reqRpc.requestId
request = reqRpc.query.get().toAPI()
info "received history query", peerId=conn.peerId, requestId=requestId, query=request
waku_store_queries.inc()
var responseRes: HistoryResult
try:
responseRes = ws.queryHandler(request)
except Exception:
error "history query failed", peerId= $conn.peerId, requestId=requestId, error=getCurrentExceptionMsg()
let error = HistoryError(kind: HistoryErrorKind.UNKNOWN).toRPC()
let response = HistoryResponseRPC(error: error)
let rpc = HistoryRPC(requestId: requestId, response: some(response))
await conn.writeLp(rpc.encode().buffer)
return
if responseRes.isErr():
error "history query failed", peerId= $conn.peerId, requestId=requestId, error=responseRes.error
let response = responseRes.toRPC()
let rpc = HistoryRPC(requestId: requestId, response: some(response))
await conn.writeLp(rpc.encode().buffer)
return
let response = responseRes.toRPC()
info "sending history response", peerId=conn.peerId, requestId=requestId, messages=response.messages.len
let rpc = HistoryRPC(requestId: requestId, response: some(response))
await conn.writeLp(rpc.encode().buffer)
ws.handler = handler
ws.codec = WakuStoreCodec
proc new*(T: type WakuStore,
peerManager: PeerManager,
rng: ref rand.HmacDrbgContext,
queryHandler: HistoryQueryHandler): T =
# Raise a defect if history query handler is nil
if queryHandler.isNil():
raise newException(NilAccessDefect, "history query handler is nil")
let ws = WakuStore(
rng: rng,
peerManager: peerManager,
queryHandler: queryHandler
)
ws.initProtocolHandler()
ws