nwaku/waku/waku_lightpush/protocol.nim

115 lines
3.5 KiB
Nim

{.push raises: [].}
import std/options, results, stew/byteutils, chronicles, chronos, metrics, bearssl/rand
import
../node/peer_manager/peer_manager,
../waku_core,
./common,
./rpc,
./rpc_codec,
./protocol_metrics,
../common/rate_limit/request_limiter
logScope:
topics = "waku lightpush"
type WakuLightPush* = ref object of LPProtocol
rng*: ref rand.HmacDrbgContext
peerManager*: PeerManager
pushHandler*: PushMessageHandler
requestRateLimiter*: RequestRateLimiter
proc handleRequest*(
wl: WakuLightPush, peerId: PeerId, buffer: seq[byte]
): Future[PushRPC] {.async.} =
let reqDecodeRes = PushRPC.decode(buffer)
var
isSuccess = false
pushResponseInfo = ""
requestId = ""
if reqDecodeRes.isErr():
pushResponseInfo = decodeRpcFailure & ": " & $reqDecodeRes.error
elif reqDecodeRes.get().request.isNone():
pushResponseInfo = emptyRequestBodyFailure
else:
let pushRpcRequest = reqDecodeRes.get()
requestId = pushRpcRequest.requestId
let
request = pushRpcRequest.request
pubSubTopic = request.get().pubSubTopic
message = request.get().message
waku_lightpush_messages.inc(labelValues = ["PushRequest"])
notice "handling lightpush request",
peer_id = peerId,
requestId = requestId,
pubsubTopic = pubsubTopic,
msg_hash = pubsubTopic.computeMessageHash(message).to0xHex()
let handleRes = await wl.pushHandler(peerId, pubsubTopic, message)
isSuccess = handleRes.isOk()
pushResponseInfo = (if isSuccess: "OK" else: handleRes.error)
if not isSuccess:
waku_lightpush_errors.inc(labelValues = [pushResponseInfo])
error "failed to push message", error = pushResponseInfo
let response = PushResponse(isSuccess: isSuccess, info: some(pushResponseInfo))
let rpc = PushRPC(requestId: requestId, response: some(response))
return rpc
proc initProtocolHandler(wl: WakuLightPush) =
proc handle(conn: Connection, proto: string) {.async.} =
var rpc: PushRPC
wl.requestRateLimiter.checkUsageLimit(WakuLightPushCodec, conn):
let buffer = await conn.readLp(DefaultMaxRpcSize)
waku_service_network_bytes.inc(
amount = buffer.len().int64, labelValues = [WakuLightPushCodec, "in"]
)
rpc = await handleRequest(wl, conn.peerId, buffer)
do:
debug "lightpush request rejected due rate limit exceeded",
peerId = conn.peerId, limit = $wl.requestRateLimiter.setting
rpc = static(
PushRPC(
## We will not copy and decode RPC buffer from stream only for requestId
## in reject case as it is comparably too expensive and opens possible
## attack surface
requestId: "N/A",
response:
some(PushResponse(isSuccess: false, info: some(TooManyRequestsMessage))),
)
)
await conn.writeLp(rpc.encode().buffer)
## For lightpush might not worth to measure outgoing trafic as it is only
## small respones about success/failure
wl.handler = handle
wl.codec = WakuLightPushCodec
proc new*(
T: type WakuLightPush,
peerManager: PeerManager,
rng: ref rand.HmacDrbgContext,
pushHandler: PushMessageHandler,
rateLimitSetting: Option[RateLimitSetting] = none[RateLimitSetting](),
): T =
let wl = WakuLightPush(
rng: rng,
peerManager: peerManager,
pushHandler: pushHandler,
requestRateLimiter: newRequestRateLimiter(rateLimitSetting),
)
wl.initProtocolHandler()
setServiceLimitMetric(WakuLightpushCodec, rateLimitSetting)
return wl