# beacon_chain # Copyright (c) 2021-2023 Status Research & Development GmbH # Licensed and distributed under either of # * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT). # * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0). # at your option. This file may not be copied, modified, or distributed except according to those terms. import common const ServiceName = "fallback_service" FAIL_TIME_OFFSETS = [ TimeOffset.init(-(MAXIMUM_GOSSIP_CLOCK_DISPARITY.nanoseconds)), TimeOffset.init(MAXIMUM_GOSSIP_CLOCK_DISPARITY.nanoseconds * 4) ] WARN_TIME_OFFSETS = [ TimeOffset.init(-(MAXIMUM_GOSSIP_CLOCK_DISPARITY.nanoseconds div 2)), TimeOffset.init(MAXIMUM_GOSSIP_CLOCK_DISPARITY.nanoseconds * 2), ] NOTE_TIME_OFFSETS = [ TimeOffset.init(-(MAXIMUM_GOSSIP_CLOCK_DISPARITY.nanoseconds div 4)), TimeOffset.init(MAXIMUM_GOSSIP_CLOCK_DISPARITY.nanoseconds), ] declareGauge validator_client_time_offset, "Wall clock offset(s) between validator client and beacon node(s)", labels = ["node"] logScope: service = ServiceName proc nodesCount*(vc: ValidatorClientRef, statuses: set[RestBeaconNodeStatus], roles: set[BeaconNodeRole] = {}): int = if len(roles) == 0: vc.beaconNodes.countIt(it.status in statuses) else: vc.beaconNodes.countIt((it.roles * roles != {}) and (it.status in statuses)) proc filterNodes*(vc: ValidatorClientRef, statuses: set[RestBeaconNodeStatus], roles: set[BeaconNodeRole] = {}): seq[BeaconNodeServerRef] = if len(roles) == 0: vc.beaconNodes.filterIt(it.status in statuses) else: vc.beaconNodes.filterIt((it.roles * roles != {}) and (it.status in statuses)) proc nonameNodes*(vc: ValidatorClientRef): seq[BeaconNodeServerRef] = vc.beaconNodes.filterIt(it.status == RestBeaconNodeStatus.Noname) proc offlineNodes*(vc: ValidatorClientRef): seq[BeaconNodeServerRef] = vc.beaconNodes.filterIt(it.status == RestBeaconNodeStatus.Offline) proc otherNodes*(vc: ValidatorClientRef): seq[BeaconNodeServerRef] = vc.beaconNodes.filterIt(it.status != RestBeaconNodeStatus.Synced) proc otherNodesCount*(vc: ValidatorClientRef): int = vc.beaconNodes.countIt(it.status != RestBeaconNodeStatus.Synced) proc preGenesisNodes*(vc: ValidatorClientRef): seq[BeaconNodeServerRef] = vc.beaconNodes.filterIt(it.status notin {RestBeaconNodeStatus.Synced, RestBeaconNodeStatus.OptSynced}) proc waitNodes*(vc: ValidatorClientRef, timeoutFut: Future[void], statuses: set[RestBeaconNodeStatus], roles: set[BeaconNodeRole], waitChanges: bool) {.async.} = doAssert(not(isNil(vc.fallbackService))) var iterations = 0 while true: if not(waitChanges) or (iterations != 0): if vc.nodesCount(statuses, roles) != 0: break if vc.fallbackService.changesEvent.isSet(): vc.fallbackService.changesEvent.clear() if isNil(timeoutFut): await vc.fallbackService.changesEvent.wait() else: let breakLoop = block: let waitFut = vc.fallbackService.changesEvent.wait() try: discard await race(waitFut, timeoutFut) except CancelledError as exc: if not(waitFut.finished()): await waitFut.cancelAndWait() raise exc if not(waitFut.finished()): await waitFut.cancelAndWait() true else: false if breakLoop: break inc(iterations) proc checkName*( node: BeaconNodeServerRef): RestBeaconNodeStatus {.raises: [].} = ## Could return only {Invalid, Noname, Offline} logScope: endpoint = node let client = block: let res = initClient(node.uri) if res.isErr(): return case res.error of CriticalHttpAddressError: RestBeaconNodeStatus.Invalid of RecoverableHttpAddressError: RestBeaconNodeStatus.Noname res.get() node.client = client RestBeaconNodeStatus.Offline proc checkCompatible( vc: ValidatorClientRef, node: BeaconNodeServerRef ): Future[RestBeaconNodeStatus] {.async.} = ## Could return only {Offline, Incompatible, Compatible} logScope: endpoint = node let info = try: debug "Requesting beacon node network configuration" let res = await node.client.getSpecVC() res.data.data except CancelledError as exc: debug "Configuration request was interrupted" raise exc except RestError as exc: if node.status != RestBeaconNodeStatus.Offline: debug "Unable to obtain beacon node's configuration", error_name = exc.name, error_message = exc.msg return RestBeaconNodeStatus.Offline except CatchableError as exc: if node.status != RestBeaconNodeStatus.Offline: error "Unexpected exception", error_name = exc.name, error_message = exc.msg return RestBeaconNodeStatus.Offline let genesis = try: debug "Requesting beacon node genesis information" let res = await node.client.getGenesis() res.data.data except CancelledError as exc: debug "Genesis request was interrupted" raise exc except RestError as exc: if node.status != RestBeaconNodeStatus.Offline: debug "Unable to obtain beacon node's genesis", error_name = exc.name, error_message = exc.msg return RestBeaconNodeStatus.Offline except CatchableError as exc: if node.status != RestBeaconNodeStatus.Offline: error "Unexpected exception", error_name = exc.name, error_message = exc.msg return RestBeaconNodeStatus.Offline let genesisFlag = (genesis != vc.beaconGenesis) configFlag = not(checkConfig(info)) node.config = info node.genesis = Opt.some(genesis) return if configFlag or genesisFlag: if node.status != RestBeaconNodeStatus.Incompatible: warn "Beacon node has incompatible configuration", genesis_flag = genesisFlag, config_flag = configFlag RestBeaconNodeStatus.Incompatible else: let res = vc.updateRuntimeConfig(node, node.config) if res.isErr(): warn "Beacon nodes report different configuration values", reason = res.error RestBeaconNodeStatus.Incompatible else: RestBeaconNodeStatus.Compatible proc checkSync( vc: ValidatorClientRef, node: BeaconNodeServerRef ): Future[RestBeaconNodeStatus] {.async.} = ## Could return only {Offline, NotSynced, Synced, OptSynced} logScope: endpoint = node let syncInfo = try: debug "Requesting beacon node sync status" let res = await node.client.getSyncingStatus() res.data.data except CancelledError as exc: debug "Sync status request was interrupted" raise exc except RestError as exc: if node.status != RestBeaconNodeStatus.Offline: debug "Unable to obtain beacon node's sync status", error_name = exc.name, error_message = exc.msg return RestBeaconNodeStatus.Offline except CatchableError as exc: if node.status != RestBeaconNodeStatus.Offline: error "Unexpected exception", error_name = exc.name, error_message = exc.msg return RestBeaconNodeStatus.Offline node.syncInfo = Opt.some(syncInfo) let res = block: let optimistic = if syncInfo.is_optimistic.isNone(): "none" else: $syncInfo.is_optimistic.get() if not(syncInfo.is_syncing) or (syncInfo.sync_distance < SYNC_TOLERANCE): if not(syncInfo.is_optimistic.get(false)): RestBeaconNodeStatus.Synced else: RestBeaconNodeStatus.OptSynced else: RestBeaconNodeStatus.NotSynced return res proc checkOnline( node: BeaconNodeServerRef ): Future[RestBeaconNodeStatus] {.async.} = ## Could return only {Offline, Online}. logScope: endpoint = node debug "Checking beacon node status" let agent = try: let res = await node.client.getNodeVersion() res.data.data except CancelledError as exc: debug "Status request was interrupted" raise exc except RestError as exc: debug "Unable to check beacon node's status", error_name = exc.name, error_message = exc.msg return RestBeaconNodeStatus.Offline except CatchableError as exc: error "Unexpected exception", error_name = exc.name, error_message = exc.msg return RestBeaconNodeStatus.Offline node.ident = Opt.some(agent.version) return RestBeaconNodeStatus.Online func getReason(status: RestBeaconNodeStatus): string = case status of RestBeaconNodeStatus.Invalid: "Beacon node address invalid" of RestBeaconNodeStatus.Noname: "Beacon node address cannot be resolved" of RestBeaconNodeStatus.Offline: "Connection with node has been lost" of RestBeaconNodeStatus.Online: "Connection with node has been established" else: "Beacon node reports" proc checkNode(vc: ValidatorClientRef, node: BeaconNodeServerRef): Future[bool] {.async.} = let nstatus = node.status debug "Checking beacon node", endpoint = node, status = node.status if nstatus in {RestBeaconNodeStatus.Noname}: let status = node.checkName() failure = ApiNodeFailure.init(ApiFailure.NoError, "checkName", node, status.getReason()) node.updateStatus(status, failure) if status != RestBeaconNodeStatus.Offline: return nstatus != status if nstatus in {RestBeaconNodeStatus.Offline, RestBeaconNodeStatus.UnexpectedCode, RestBeaconNodeStatus.UnexpectedResponse, RestBeaconNodeStatus.InternalError}: let status = await node.checkOnline() failure = ApiNodeFailure.init(ApiFailure.NoError, "checkOnline", node, status.getReason()) node.updateStatus(status, failure) if status != RestBeaconNodeStatus.Online: return nstatus != status if nstatus in {RestBeaconNodeStatus.Offline, RestBeaconNodeStatus.UnexpectedCode, RestBeaconNodeStatus.UnexpectedResponse, RestBeaconNodeStatus.InternalError, RestBeaconNodeStatus.Online, RestBeaconNodeStatus.Incompatible}: let status = await vc.checkCompatible(node) failure = ApiNodeFailure.init(ApiFailure.NoError, "checkCompatible", node, status.getReason()) node.updateStatus(status, failure) if status != RestBeaconNodeStatus.Compatible: return nstatus != status if nstatus in {RestBeaconNodeStatus.Offline, RestBeaconNodeStatus.UnexpectedCode, RestBeaconNodeStatus.UnexpectedResponse, RestBeaconNodeStatus.InternalError, RestBeaconNodeStatus.Online, RestBeaconNodeStatus.Incompatible, RestBeaconNodeStatus.Compatible, RestBeaconNodeStatus.OptSynced, RestBeaconNodeStatus.NotSynced}: let status = await vc.checkSync(node) failure = ApiNodeFailure.init(ApiFailure.NoError, "checkSync", node, status.getReason()) node.updateStatus(status, failure) return nstatus != status proc checkNodes*(service: FallbackServiceRef): Future[bool] {.async.} = let vc = service.client nodesToCheck = if vc.genesisEvent.isSet(): service.client.otherNodes() else: service.client.preGenesisNodes() pendingChecks = nodesToCheck.mapIt(service.client.checkNode(it)) var res = false try: await allFutures(pendingChecks) for fut in pendingChecks: if fut.completed() and fut.read(): res = true except CancelledError as exc: let pending = pendingChecks .filterIt(not(it.finished())).mapIt(it.cancelAndWait()) await noCancel allFutures(pending) raise exc return res proc checkOffsetStatus(node: BeaconNodeServerRef, offset: TimeOffset) = logScope: node = node node.timeOffset = Opt.some(offset) validator_client_time_offset.set(float64(offset.milliseconds()), @[$node]) debug "Beacon node time offset", time_offset = offset let updateStatus = if (offset <= WARN_TIME_OFFSETS[0]) or (offset >= WARN_TIME_OFFSETS[1]): warn "Beacon node has significant time offset", time_offset = offset if (offset <= FAIL_TIME_OFFSETS[0]) or (offset >= FAIL_TIME_OFFSETS[1]): # Beacon node's clock is out of acceptable offsets, we marking this # beacon node and remote it from the list of working nodes. warn "Beacon node has enormous time offset", time_offset = offset let failure = ApiNodeFailure.init(ApiFailure.NoError, "checkTimeOffsetStatus()", node, 200, "Beacon node has enormous time offset") node.updateStatus(RestBeaconNodeStatus.BrokenClock, failure) false else: true elif (offset <= NOTE_TIME_OFFSETS[0]) or (offset >= NOTE_TIME_OFFSETS[1]): info "Beacon node has notable time offset", time_offset = offset true else: true if updateStatus: if node.status == RestBeaconNodeStatus.BrokenClock: # Beacon node's clock has been recovered to some acceptable offset, so we # could restore beacon node. let failure = ApiNodeFailure.init(ApiFailure.NoError, "checkTimeOffsetStatus()", node, 200, "Beacon node has acceptable time offset") node.updateStatus(RestBeaconNodeStatus.Offline, failure) proc runTimeMonitor(service: FallbackServiceRef, node: BeaconNodeServerRef) {.async.} = const NimbusExtensionsLog = "Beacon node do not support nimbus extensions" let vc = service.client roles = AllBeaconNodeRoles statuses = AllBeaconNodeStatuses - {RestBeaconNodeStatus.Offline} logScope: node = node if BeaconNodeRole.NoTimeCheck in node.roles: debug "Beacon node time offset checks disabled" return while true: while node.status notin statuses: await vc.waitNodes(nil, statuses, roles, true) if RestBeaconNodeFeature.NoNimbusExtensions in node.features: return let tres = try: let delay = vc.processingDelay.valueOr: ZeroDuration res = await node.client.getTimeOffset(delay) Opt.some(res) except RestResponseError as exc: case exc.status of 400: debug "Beacon node returns invalid response", status = $exc.status, reason = $exc.msg, error_message = $exc.message else: notice NimbusExtensionsLog, status = $exc.status, reason = $exc.msg, error_message = $exc.message # Exiting loop node.features.incl(RestBeaconNodeFeature.NoNimbusExtensions) return except RestError as exc: debug "Unable to obtain beacon node's time offset", reason = $exc.msg notice NimbusExtensionsLog node.features.incl(RestBeaconNodeFeature.NoNimbusExtensions) return except CancelledError as exc: raise exc except CatchableError as exc: warn "An unexpected error occurred while asking for time offset", reason = $exc.msg, error = $exc.name notice NimbusExtensionsLog node.features.incl(RestBeaconNodeFeature.NoNimbusExtensions) return if tres.isSome(): checkOffsetStatus(node, TimeOffset.init(tres.get())) else: debug "Beacon node's time offset was not updated" await service.waitForNextSlot() proc processTimeMonitoring(service: FallbackServiceRef) {.async.} = let vc = service.client blockNodes = vc.filterNodes( ResolvedBeaconNodeStatuses, AllBeaconNodeRoles) var pendingChecks: seq[Future[void]] try: for node in blockNodes: pendingChecks.add(service.runTimeMonitor(node)) await allFutures(pendingChecks) except CancelledError as exc: let pending = pendingChecks .filterIt(not(it.finished())).mapIt(it.cancelAndWait()) await noCancel allFutures(pending) raise exc except CatchableError as exc: warn "An unexpected error occurred while running time monitoring", reason = $exc.msg, error = $exc.name return proc mainLoop(service: FallbackServiceRef) {.async.} = let vc = service.client service.state = ServiceState.Running debug "Service started" let timeMonitorFut = processTimeMonitoring(service) try: await vc.preGenesisEvent.wait() except CancelledError: debug "Service interrupted" if not(timeMonitorFut.finished()): await timeMonitorFut.cancelAndWait() return except CatchableError as exc: warn "Service crashed with unexpected error", err_name = exc.name, err_msg = exc.msg return while true: # This loop could look much more nicer/better, when # https://github.com/nim-lang/Nim/issues/19911 will be fixed, so it could # become safe to combine loops, breaks and exception handlers. let breakLoop = try: if await service.checkNodes(): service.changesEvent.fire() await sleepAsync(2.seconds) false except CancelledError as exc: debug "Service interrupted" if not(timeMonitorFut.finished()): await timeMonitorFut.cancelAndWait() true except CatchableError as exc: error "Service crashed with unexpected error", err_name = exc.name, err_msg = exc.msg true if breakLoop: break proc init*(t: typedesc[FallbackServiceRef], vc: ValidatorClientRef): Future[FallbackServiceRef] {.async.} = logScope: service = ServiceName var res = FallbackServiceRef(name: ServiceName, client: vc, state: ServiceState.Initialized, changesEvent: newAsyncEvent()) debug "Initializing service" return res proc start*(service: FallbackServiceRef) = service.lifeFut = mainLoop(service)