fix broken metrics during replay (#2090)

* move metrics out of state transition
* add validator count metric
* remove expensive beacon_current_validators, beacon_previous_validators
metrics (they should be reimplemented with cache), add cheap
beacon_active_validators to approximate
* remove unused validator count metrics
* tidy imports/defects

beacon_chain/block_pools/block_pools_types.nim

@@ -5,6 +5,8 @@
 #   * 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.
 
+{.push raises: [Defect].}
+
 import
   # Standard library
   std/[deques, strformat, tables, hashes],
@@ -206,22 +208,31 @@ template validator_keys*(e: EpochRef): untyped = e.validator_key_store[1][]
 template head*(v: ChainDagRef): BlockRef = v.headState.blck
 
 func shortLog*(v: BlockSlot): string =
-  if v.blck.slot == v.slot:
+  try:
-    &"{v.blck.root.data.toOpenArray(0, 3).toHex()}:{v.blck.slot}"
+    if v.blck.slot == v.slot:
-  else: # There was a gap - log it
+      &"{v.blck.root.data.toOpenArray(0, 3).toHex()}:{v.blck.slot}"
-    &"{v.blck.root.data.toOpenArray(0, 3).toHex()}:{v.blck.slot}@{v.slot}"
+    else: # There was a gap - log it
+      &"{v.blck.root.data.toOpenArray(0, 3).toHex()}:{v.blck.slot}@{v.slot}"
+  except ValueError as err:
+    err.msg # Shouldn't happen - but also shouldn't crash!
 
 func shortLog*(v: BlockRef): string =
-  if v == nil:
+  try:
-    "BlockRef(nil)"
+    if v == nil:
-  else:
+      "BlockRef(nil)"
-   &"{v.root.data.toOpenArray(0, 3).toHex()}:{v.slot}"
+    else:
+      &"{v.root.data.toOpenArray(0, 3).toHex()}:{v.slot}"
+  except ValueError as err:
+    err.msg # Shouldn't happen - but also shouldn't crash!
 
 func shortLog*(v: EpochRef): string =
-  if v == nil:
+  try:
-    "EpochRef(nil)"
+    if v == nil:
-  else:
+      "EpochRef(nil)"
-    &"(epoch ref: {v.epoch})"
+    else:
+      &"(epoch ref: {v.epoch})"
+  except ValueError as err:
+    err.msg # Shouldn't happen - but also shouldn't crash!
 
 chronicles.formatIt BlockSlot: shortLog(it)
 chronicles.formatIt BlockRef: shortLog(it)

beacon_chain/block_pools/chain_dag.nim

@@ -14,15 +14,28 @@ import
   ../spec/[
     crypto, datatypes, digest, helpers, validator, state_transition,
     beaconstate],
-  block_pools_types, quarantine
+  ./block_pools_types, ./quarantine
 
 export block_pools_types, helpers
 
+# https://github.com/ethereum/eth2.0-metrics/blob/master/metrics.md#interop-metrics
+declareGauge beacon_head_root, "Root of the head block of the beacon chain"
+declareGauge beacon_head_slot, "Slot of the head block of the beacon chain"
+
+# https://github.com/ethereum/eth2.0-metrics/blob/master/metrics.md#interop-metrics
+declareGauge beacon_finalized_epoch, "Current finalized epoch" # On epoch transition
+declareGauge beacon_finalized_root, "Current finalized root" # On epoch transition
+declareGauge beacon_current_justified_epoch, "Current justified epoch" # On epoch transition
+declareGauge beacon_current_justified_root, "Current justified root" # On epoch transition
+declareGauge beacon_previous_justified_epoch, "Current previously justified epoch" # On epoch transition
+declareGauge beacon_previous_justified_root, "Current previously justified root" # On epoch transition
+
 declareCounter beacon_reorgs_total, "Total occurrences of reorganizations of the chain" # On fork choice
 declareCounter beacon_state_data_cache_hits, "EpochRef hits"
 declareCounter beacon_state_data_cache_misses, "EpochRef misses"
 declareCounter beacon_state_rewinds, "State database rewinds"
 
+declareGauge beacon_active_validators, "Number of validators in the active validator set"
 declareGauge beacon_pending_deposits, "Number of pending deposits (state.eth1_data.deposit_count - state.eth1_deposit_index)" # On block
 declareGauge beacon_processed_deposits_total, "Number of total deposits included on chain" # On block
 
@@ -810,7 +823,6 @@ proc updateHead*(
 
   let
     lastHead = dag.head
-  dag.db.putHeadBlock(newHead.root)
 
   # Start off by making sure we have the right state - updateStateData will try
   # to use existing in-memory states to make this smooth
@@ -818,6 +830,15 @@ proc updateHead*(
   updateStateData(
     dag, dag.headState, newHead.atSlot(newHead.slot), false, cache)
 
+  dag.db.putHeadBlock(newHead.root)
+
+  let
+    finalizedHead = newHead.atEpochStart(
+      dag.headState.data.data.finalized_checkpoint.epoch)
+
+  doAssert (not finalizedHead.blck.isNil),
+    "Block graph should always lead to a finalized block"
+
   if not lastHead.isAncestorOf(newHead):
     notice "Updated head block with chain reorg",
       lastHead = shortLog(lastHead),
@@ -838,9 +859,6 @@ proc updateHead*(
       stateSlot = shortLog(dag.headState.data.data.slot),
       justified = shortLog(dag.headState.data.data.current_justified_checkpoint),
       finalized = shortLog(dag.headState.data.data.finalized_checkpoint)
-  let
-    finalizedHead = newHead.atEpochStart(
-      dag.headState.data.data.finalized_checkpoint.epoch)
 
   # https://github.com/ethereum/eth2.0-metrics/blob/master/metrics.md#additional-metrics
   if dag.headState.data.data.eth1_data.deposit_count < high(int64).uint64:
@@ -850,12 +868,28 @@ proc updateHead*(
     beacon_processed_deposits_total.set(
       dag.headState.data.data.eth1_deposit_index.int64)
 
-  doAssert (not finalizedHead.blck.isNil),
+  beacon_head_root.set newHead.root.toGaugeValue
-    "Block graph should always lead to a finalized block"
+  beacon_head_slot.set newHead.slot.int64
+
+  if lastHead.slot.epoch != newHead.slot.epoch:
+    # Epoch updated - in theory, these could happen when the wall clock
+    # changes epoch, even if there is no new block / head, but we'll delay
+    # updating them until a block confirms the change
+    beacon_current_justified_epoch.set(
+      dag.headState.data.data.current_justified_checkpoint.epoch.int64)
+    beacon_current_justified_root.set(
+      dag.headState.data.data.current_justified_checkpoint.root.toGaugeValue)
+    beacon_previous_justified_epoch.set(
+      dag.headState.data.data.previous_justified_checkpoint.epoch.int64)
+    beacon_previous_justified_root.set(
+      dag.headState.data.data.previous_justified_checkpoint.root.toGaugeValue)
+
+    let epochRef = getEpochRef(dag, newHead, newHead.slot.epoch)
+    beacon_active_validators.set(
+      epochRef.shuffled_active_validator_indices.lenu64().int64)
 
   if finalizedHead != dag.finalizedHead:
     block: # Remove states, walking slot by slot
-      discard
       var cur = finalizedHead
       while cur != dag.finalizedHead:
         # TODO This is a quick fix to prune some states from the database, but
@@ -912,6 +946,11 @@ proc updateHead*(
       finalizedHead = shortLog(finalizedHead),
       heads = dag.heads.len
 
+    beacon_finalized_epoch.set(
+      dag.headState.data.data.finalized_checkpoint.epoch.int64)
+    beacon_finalized_root.set(
+      dag.headState.data.data.finalized_checkpoint.root.toGaugeValue)
+
 proc isInitialized*(T: type ChainDAGRef, db: BeaconChainDB): bool =
   let
     headBlockRoot = db.getHeadBlock()

beacon_chain/block_pools/clearance.nim

@@ -10,7 +10,7 @@
 import
   std/tables,
   chronicles,
-  metrics, stew/results,
+  stew/results,
   ../extras, ../time,
   ../spec/[crypto, datatypes, digest, helpers, signatures, state_transition],
   ./block_pools_types, ./chain_dag, ./quarantine

beacon_chain/block_pools/quarantine.nim

@@ -5,20 +5,20 @@
 #   * 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.
 
+{.push raises: [Defect].}
+
 import
-  chronicles, tables, options,
+  std/[tables, options],
+  chronicles,
   stew/bitops2,
-  metrics,
   ../spec/[crypto, datatypes, digest],
-  block_pools_types
+  ./block_pools_types
 
 export options, block_pools_types
 
 logScope:
   topics = "quarant"
 
-{.push raises: [Defect].}
-
 func checkMissing*(quarantine: var QuarantineRef): seq[FetchRecord] =
   ## Return a list of blocks that we should try to resolve from other client -
   ## to be called periodically but not too often (once per slot?)

beacon_chain/block_pools/spec_cache.nim

@@ -5,6 +5,8 @@
 #   * 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.
 
+{.push raises: [Defect].}
+
 import
   std/[algorithm, sequtils, sets],
   chronicles,

beacon_chain/eth2_processor.nim

@@ -36,10 +36,6 @@ declareHistogram beacon_block_delay,
 declareHistogram beacon_store_block_duration_seconds,
   "storeBlock() duration", buckets = [0.25, 0.5, 1, 2, 4, 8, Inf]
 
-# https://github.com/ethereum/eth2.0-metrics/blob/master/metrics.md#interop-metrics
-declareGauge beacon_head_root, "Root of the head block of the beacon chain"
-declareGauge beacon_head_slot, "Slot of the head block of the beacon chain"
-
 type
   GetWallTimeFn* = proc(): BeaconTime {.gcsafe, raises: [Defect].}
 
@@ -81,14 +77,15 @@ proc updateHead*(self: var Eth2Processor, wallSlot: Slot) =
 
   # Store the new head in the chain DAG - this may cause epochs to be
   # justified and finalized
-  let oldFinalized = self.chainDag.finalizedHead.blck
+  let
+    oldFinalized = self.chainDag.finalizedHead.blck
+    oldHead = self.chainDag.head
 
   self.chainDag.updateHead(newHead, self.quarantine)
-  beacon_head_root.set newHead.root.toGaugeValue
-  beacon_head_slot.set newHead.slot.int64
 
   # Cleanup the fork choice v2 if we have a finalized head
   if oldFinalized != self.chainDag.finalizedHead.blck:
+
     self.attestationPool[].prune()
 
 proc dumpBlock[T](

beacon_chain/nimbus_beacon_node.nim

@@ -45,8 +45,8 @@ template init(T: type RpcHttpServer, ip: ValidIpAddress, port: Port): T =
   newRpcHttpServer([initTAddress(ip, port)])
 
 # https://github.com/ethereum/eth2.0-metrics/blob/master/metrics.md#interop-metrics
-declareGauge beacon_slot,
+declareGauge beacon_slot, "Latest slot of the beacon chain state"
-  "Latest slot of the beacon chain state"
+declareGauge beacon_current_epoch, "Current epoch"
 
 # Finalization tracking
 declareGauge finalization_delay,
@@ -540,6 +540,8 @@ proc onSlotStart(node: BeaconNode, lastSlot, scheduledSlot: Slot) {.async.} =
     nextSlot = slot + 1
 
   beacon_slot.set slot.int64
+  beacon_current_epoch.set slot.epoch.int64
+
   finalization_delay.set scheduledSlot.epoch.int64 - finalizedEpoch.int64
 
   if node.config.verifyFinalization:

beacon_chain/spec/beaconstate.nim

@@ -8,8 +8,9 @@
 {.push raises: [Defect].}
 
 import
-  tables, algorithm, math, sequtils, options,
+  std/[tables, algorithm, math, sequtils, options],
-  json_serialization/std/sets, chronicles,
+  json_serialization/std/sets,
+  chronicles,
   ../extras, ../ssz/merkleization,
   ./crypto, ./datatypes, ./digest, ./helpers, ./signatures, ./validator,
   ../../nbench/bench_lab

beacon_chain/spec/crypto.nim

@@ -25,7 +25,7 @@
 
 import
   # Standard library
-  std/[options, tables],
+  std/[options, hashes, tables],
   # Internal
   ./digest,
   # Status
@@ -33,9 +33,7 @@ import
   blscurve,
   chronicles,
   json_serialization,
-  nimcrypto/utils as ncrutils,
+  nimcrypto/utils as ncrutils
-  # Standard library
-  hashes
 
 export results, json_serialization
 

beacon_chain/spec/datatypes.nim

@@ -25,7 +25,7 @@
 {.push raises: [Defect].}
 
 import
-  macros, hashes, json, strutils, tables, typetraits,
+  std/[macros, hashes, json, strutils, tables, typetraits],
   stew/[byteutils], chronicles,
   json_serialization/types as jsonTypes,
   ../version, ../ssz/types as sszTypes, ./crypto, ./digest, ./presets

beacon_chain/spec/digest.nim

@@ -28,7 +28,6 @@ import
   chronicles,
   nimcrypto/[sha2, hash],
   stew/byteutils,
-  hashes,
   eth/common/eth_types_json_serialization,
   blscurve
 

beacon_chain/spec/keystore.nim

@@ -5,6 +5,8 @@
 #   * 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.
 
+{.push raises: [Defect].}
+
 import
   # Standard library
   std/[algorithm, math, parseutils, strformat, strutils, typetraits, unicode],
@@ -24,7 +26,6 @@ import nimcrypto/utils as ncrutils
 export
   results, burnMem, writeValue, readValue
 
-{.push raises: [Defect].}
 {.localPassC: "-fno-lto".} # no LTO for crypto
 
 type

beacon_chain/spec/presets.nim

@@ -1,10 +1,17 @@
-import
+# beacon_chain
-  macros, strutils, parseutils, tables,
+# Copyright (c) 2018-2020 Status Research & Development GmbH
-  stew/endians2,
+# Licensed and distributed under either of
-  preset_values
+#   * 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.
 
 {.push raises: [Defect].}
 
+import
+  std/[macros, strutils, parseutils, tables],
+  stew/endians2,
+  preset_values
+
 export
   PresetValue, toBytesBE
 

beacon_chain/spec/state_transition.nim

@@ -20,40 +20,14 @@
 {.push raises: [Defect].}
 
 import
-  tables,
+  std/tables,
   chronicles,
   stew/results,
   ../extras, ../ssz/merkleization, metrics,
-  datatypes, crypto, digest, helpers, signatures, validator,
+  ./datatypes, ./crypto, ./digest, ./helpers, ./signatures, ./validator,
-  state_transition_block, state_transition_epoch,
+  ./state_transition_block, ./state_transition_epoch,
   ../../nbench/bench_lab
 
-# https://github.com/ethereum/eth2.0-metrics/blob/master/metrics.md#additional-metrics
-declareGauge beacon_current_validators, """Number of status="pending|active|exited|withdrawable" validators in current epoch""" # On epoch transition
-declareGauge beacon_previous_validators, """Number of status="pending|active|exited|withdrawable" validators in previous epoch""" # On epoch transition
-
-func get_epoch_validator_count(state: BeaconState): int64 {.nbench.} =
-  # https://github.com/ethereum/eth2.0-metrics/blob/master/metrics.md#additional-metrics
-  #
-  # This O(n) loop doesn't add to the algorithmic complexity of the epoch
-  # transition -- registry update already does this. It is not great, but
-  # isn't new, either. If profiling shows issues some of this can be loop
-  # fusion'ed.
-  for index, validator in state.validators:
-    # These work primarily for the `beacon_current_validators` metric defined
-    # as 'Number of status="pending|active|exited|withdrawable" validators in
-    # current epoch'. This is, in principle, equivalent to checking whether a
-    # validator's either at less than MAX_EFFECTIVE_BALANCE, or has withdrawn
-    # already because withdrawable_epoch has passed, which more precisely has
-    # intuitive meaning of all-the-current-relevant-validators. So, check for
-    # not-(either (not-even-pending) or withdrawn). That is validators change
-    # from not-even-pending to pending to active to exited to withdrawable to
-    # withdrawn, and this avoids bugs on potential edge cases and off-by-1's.
-    if (validator.activation_epoch != FAR_FUTURE_EPOCH or
-          validator.effective_balance > MAX_EFFECTIVE_BALANCE) and
-       validator.withdrawable_epoch > get_current_epoch(state):
-      result += 1
-
 # https://github.com/ethereum/eth2.0-specs/blob/v1.0.0/specs/phase0/beacon-chain.md#beacon-chain-state-transition-function
 proc verify_block_signature*(
     state: BeaconState, signed_block: SomeSignedBeaconBlock): bool {.nbench.} =
@@ -134,14 +108,11 @@ proc advance_slot(
   let is_epoch_transition = (state.data.slot + 1).isEpoch
   if is_epoch_transition:
     # Note: Genesis epoch = 0, no need to test if before Genesis
-    beacon_previous_validators.set(get_epoch_validator_count(state.data))
     process_epoch(state.data, updateFlags, epochCache)
     clear_epoch_from_cache(
       epochCache, (state.data.slot + 1).compute_epoch_at_slot)
 
   state.data.slot += 1
-  if is_epoch_transition:
-    beacon_current_validators.set(get_epoch_validator_count(state.data))
 
   # The root must be updated on every slot update, or the next `process_slot`
   # will be incorrect

beacon_chain/spec/state_transition_block.nim

@@ -20,7 +20,8 @@
 {.push raises: [Defect].}
 
 import
-  algorithm, collections/sets, chronicles, options, sequtils, sets,
+  std/[algorithm, collections/sets, options, sequtils, sets],
+  chronicles,
   ../extras, ../ssz/merkleization, metrics,
   ./beaconstate, ./crypto, ./datatypes, ./digest, ./helpers, ./validator,
   ./signatures, ./presets,

beacon_chain/spec/state_transition_epoch.nim

@@ -21,7 +21,7 @@
 
 import
   std/[math, sequtils, tables, algorithm],
-  stew/[bitops2], chronicles, metrics,
+  stew/[bitops2], chronicles,
   ../extras,
   ../ssz/merkleization,
   ./beaconstate, ./crypto, ./datatypes, ./digest, ./helpers, ./validator,
@@ -32,22 +32,6 @@ import
 
 logScope: topics = "consens"
 
-# https://github.com/ethereum/eth2.0-metrics/blob/master/metrics.md#interop-metrics
-declareGauge beacon_finalized_epoch, "Current finalized epoch" # On epoch transition
-declareGauge beacon_finalized_root, "Current finalized root" # On epoch transition
-declareGauge beacon_current_justified_epoch, "Current justified epoch" # On epoch transition
-declareGauge beacon_current_justified_root, "Current justified root" # On epoch transition
-declareGauge beacon_previous_justified_epoch, "Current previously justified epoch" # On epoch transition
-declareGauge beacon_previous_justified_root, "Current previously justified root" # On epoch transition
-
-# Non-spec
-declareGauge epoch_transition_justification_and_finalization, "Epoch transition justification and finalization time"
-declareGauge epoch_transition_times_rewards_and_penalties, "Epoch transition reward and penalty time"
-declareGauge epoch_transition_registry_updates, "Epoch transition registry updates time"
-declareGauge epoch_transition_slashings, "Epoch transition slashings time"
-declareGauge epoch_transition_final_updates, "Epoch transition final updates time"
-declareGauge beacon_current_epoch, "Current epoch"
-
 type
   # Caches for computing justificiation, rewards and penalties - based on
   # implementation in Lighthouse:
@@ -633,16 +617,3 @@ proc process_epoch*(state: var BeaconState, updateFlags: UpdateFlags,
 
   # https://github.com/ethereum/eth2.0-specs/blob/v1.0.0/specs/phase0/beacon-chain.md#final-updates
   process_final_updates(state)
-
-  # Once per epoch metrics
-  beacon_current_epoch.set(currentEpoch.int64)
-  beacon_finalized_epoch.set(state.finalized_checkpoint.epoch.int64)
-  beacon_finalized_root.set(state.finalized_checkpoint.root.toGaugeValue)
-  beacon_current_justified_epoch.set(
-    state.current_justified_checkpoint.epoch.int64)
-  beacon_current_justified_root.set(
-    state.current_justified_checkpoint.root.toGaugeValue)
-  beacon_previous_justified_epoch.set(
-    state.previous_justified_checkpoint.epoch.int64)
-  beacon_previous_justified_root.set(
-    state.previous_justified_checkpoint.root.toGaugeValue)

beacon_chain/spec/validator.nim

@@ -9,7 +9,7 @@
 {.push raises: [Defect].}
 
 import
-  options, math, tables,
+  std/[options, math, tables],
   ./datatypes, ./digest, ./helpers
 
 const

beacon_chain/spec/weak_subjectivity.nim

@@ -1,8 +1,15 @@
-import
+# beacon_chain
-  datatypes, digest, helpers
+# Copyright (c) 2018-2020 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.
 
 {.push raises: [Defect].}
 
+import
+  ./datatypes, ./digest, ./helpers
+
 const
   SAFETY_DECAY* = 10'u64
 

beacon_chain/ssz/bytes_reader.nim

@@ -1,8 +1,16 @@
+# beacon_chain
+# Copyright (c) 2018-2020 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.
+
 {.push raises: [Defect].}
+
 {.pragma: raisesssz, raises: [Defect, MalformedSszError, SszSizeMismatchError].}
 
 import
-  typetraits, options,
+  std/[typetraits, options],
   stew/[bitops2, endians2, objects],
   ../spec/[digest, datatypes], ./types, ./spec_types, ./merkleization
 

beacon_chain/ssz/dynamic_navigator.nim

@@ -1,8 +1,15 @@
+# beacon_chain
+# Copyright (c) 2018-2020 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.
+
 {.push raises: [Defect].}
 {.pragma: raisesssz, raises: [Defect, IOError, MalformedSszError, SszSizeMismatchError].}
 
 import
-  strutils, parseutils,
+  std/[strutils, parseutils],
   stew/objects, faststreams/outputs, json_serialization/writer,
   ../spec/datatypes,
   ./bytes_reader, ./types, ./navigator, ./spec_types

beacon_chain/ssz/navigator.nim

@@ -1,3 +1,10 @@
+# beacon_chain
+# Copyright (c) 2018-2020 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.
+
 {.push raises: [Defect].}
 {.pragma: raisesssz, raises: [Defect, MalformedSszError, SszSizeMismatchError].}
 

beacon_chain/ssz/spec_types.nim

@@ -1,5 +1,12 @@
+# beacon_chain
+# Copyright (c) 2018-2020 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
-  typetraits,
+  std/[typetraits],
   ../spec/[crypto, digest]
 
 # Eth2-spec-specific type handling that is not generic to SSZ

beacon_chain/ssz/ssz_serialization.nim

@@ -1,3 +1,10 @@
+# beacon_chain
+# Copyright (c) 2018-2020 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.
+
 # TODO Cannot override push, even though the function is annotated
 # nimbus-eth2/beacon_chain/ssz.nim(212, 18) Error: can raise an unlisted exception: IOError
 # {.push raises: [Defect].}
@@ -7,7 +14,7 @@
 # https://github.com/ethereum/eth2.0-specs/blob/v1.0.0/ssz/simple-serialize.md#serialization
 
 import
-  typetraits, options,
+  std/[typetraits, options],
   stew/[bitops2, endians2, objects],
   serialization, serialization/testing/tracing,
   ../spec/[digest, datatypes],

beacon_chain/ssz/types.nim

@@ -1,7 +1,14 @@
+# beacon_chain
+# Copyright (c) 2018-2020 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.
+
 {.push raises: [Defect].}
 
 import
-  tables, options, typetraits, strformat,
+  std/[tables, options, typetraits, strformat],
   stew/shims/macros, stew/[byteutils, bitops2, objects],
   serialization/[object_serialization, errors],
   ./spec_types, ./bitseqs,
@@ -14,7 +21,7 @@ const
   bytesPerChunk* = 32
 
 type
-  UintN* = SomeUnsignedInt # TODO: Add StUint here
+  UintN* = SomeUnsignedInt
   BasicType* = bool|UintN
 
   Limit* = int64

beacon_chain/validator_pool.nim

@@ -1,11 +1,13 @@
 import
-  tables, json, streams,
+  std/[tables, json, streams],
-  chronos, chronicles,
+  chronos, chronicles, metrics,
-  spec/[datatypes, crypto, digest, signatures, helpers],
-  beacon_node_types,
   json_serialization/std/[sets, net],
-  validator_slashing_protection,
+  eth/db/[kvstore, kvstore_sqlite3],
-  eth/db/[kvstore, kvstore_sqlite3]
+  ./spec/[datatypes, crypto, digest, signatures, helpers],
+  ./beacon_node_types, validator_slashing_protection
+
+declareGauge validators,
+  "Number of validators attached to the beacon node"
 
 func init*(T: type ValidatorPool,
             slashingProtectionDB: SlashingProtectionDB): T =
@@ -28,12 +30,16 @@ proc addLocalValidator*(pool: var ValidatorPool,
   pool.validators[pubKey] = v
   notice "Local validator attached", pubKey, validator = shortLog(v)
 
+  validators.set(pool.count().int64)
+
 proc addRemoteValidator*(pool: var ValidatorPool,
                          pubKey: ValidatorPubKey,
                          v: AttachedValidator) =
   pool.validators[pubKey] = v
   notice "Remote validator attached", pubKey, validator = shortLog(v)
 
+  validators.set(pool.count().int64)
+
 proc getValidator*(pool: ValidatorPool,
                    validatorKey: ValidatorPubKey): AttachedValidator =
   pool.validators.getOrDefault(validatorKey.initPubKey)

grafana/beacon_nodes_Grafana_dashboard.json

@@ -316,16 +316,10 @@
       "steppedLine": false,
       "targets": [
         {
-          "expr": "beacon_current_validators{node=\"${node}\"}",
+          "expr": "beacon_active_validators{node=\"${node}\"}",
           "interval": "",
           "legendFormat": "current validators",
           "refId": "A"
-        },
-        {
-          "expr": "beacon_current_live_validators{node=\"${node}\"}",
-          "interval": "",
-          "legendFormat": "current live validators",
-          "refId": "B"
         }
       ],
       "thresholds": [],