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BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
# beacon_chain
complete switch to beacon_chain/specs/datatypes/bellatrix (#3295)
2022-01-18 13:36:52 +00:00
# Copyright (c) 2018-2022 Status Research & Development GmbH
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
# 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
chronicles,
chaindag: don't keep backfill block table in memory (#3429) This PR names and documents the concept of the archive: a range of slots for which we have degraded functionality in terms of historical access - in particular: * we don't support rewinding to states in this range * we don't keep an in-memory representation of the block dag The archive de-facto exists in a trusted-node-synced node, but this PR gives it a name and drops the in-memory digest index. In order to satisfy `GetBlocksByRange` requests, we ensure that we have blocks for the entire archive period via backfill. Future versions may relax this further, adding a "pre-archive" period that is fully pruned. During by-slot searches in the archive (both for libp2p and rest requests), an extra database lookup is used to covert the given `slot` to a `root` - future versions will avoid this using era files which natively are indexed by `slot`. That said, the lookup is quite fast compared to the actual block loading given how trivial the table is - it's hard to measure, even. A collateral benefit of this PR is that checkpoint-synced nodes will see 100-200MB memory usage savings, thanks to the dropped in-memory cache - future pruning work will bring this benefit to full nodes as well. * document chaindag storage architecture and assumptions * look up parent using block id instead of full block in clearance (future-proofing the code against a future in which blocks come from era files) * simplify finalized block init, always writing the backfill portion to db at startup (to ensure lookups work as expected) * preallocate some extra memory for finalized blocks, to avoid immediate realloc
2022-02-26 18:16:19 +00:00
../spec/forks
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
chaindag: don't keep backfill block table in memory (#3429) This PR names and documents the concept of the archive: a range of slots for which we have degraded functionality in terms of historical access - in particular: * we don't support rewinding to states in this range * we don't keep an in-memory representation of the block dag The archive de-facto exists in a trusted-node-synced node, but this PR gives it a name and drops the in-memory digest index. In order to satisfy `GetBlocksByRange` requests, we ensure that we have blocks for the entire archive period via backfill. Future versions may relax this further, adding a "pre-archive" period that is fully pruned. During by-slot searches in the archive (both for libp2p and rest requests), an extra database lookup is used to covert the given `slot` to a `root` - future versions will avoid this using era files which natively are indexed by `slot`. That said, the lookup is quite fast compared to the actual block loading given how trivial the table is - it's hard to measure, even. A collateral benefit of this PR is that checkpoint-synced nodes will see 100-200MB memory usage savings, thanks to the dropped in-memory cache - future pruning work will bring this benefit to full nodes as well. * document chaindag storage architecture and assumptions * look up parent using block id instead of full block in clearance (future-proofing the code against a future in which blocks come from era files) * simplify finalized block init, always writing the backfill portion to db at startup (to ensure lookups work as expected) * preallocate some extra memory for finalized blocks, to avoid immediate realloc
2022-02-26 18:16:19 +00:00
export chronicles, forks
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
type
BlockId* = object
## A BlockId is the root and the slot in which that block was
## produced - there are no guarantees that this block is part of
## the canonical chain, or that we have validated it
root*: Eth2Digest
slot*: Slot
BlockSlotId* = object
## A BlockId at a slot equal to or higher than the slot of the block
bid*: BlockId
slot*: Slot
BlockRef* = ref object
## Node in object graph guaranteed to lead back to tail block, and to have
## a corresponding entry in database.
##
## All blocks identified by a `BlockRef` are valid per the state transition
## rules and that at some point were candidates for head selection. The
## ChainDAG offers stronger guarantees: it only returns `BlockRef` instances
## that are rooted in the currently finalized chain - however, these
## guarantees are valid only until the next head update - in particular,
## they are not valid across `await` calls.
##
## Block graph forms a tree - in particular, there are no cycles.
bid*: BlockId ##\
## Root that can be used to retrieve block data from database
parent*: BlockRef ##\
## Not nil, except for the tail
BlockSlot* = object
## Unique identifier for a particular fork and time in the block chain -
## normally, there's a block for every slot, but in the case a block is not
## produced, the chain progresses anyway, producing a new state for every
## slot.
blck*: BlockRef
slot*: Slot ##\
## Slot time for this BlockSlot which may differ from blck.slot when time
## has advanced without blocks
allow using `BlockId` as key in tables (#3467) `BlockId` is a type that bundles a block root with its slot number. The type can be useful as key in tables that deal with non-finalized blocks (not uniquely identified by slot) and also support pruning (drop data about older blocks by slot). Instead of creating a custom type for those use cases, this patch suggests implementing `hash` for `BlockId` to re-use the existing type.
2022-03-07 13:56:58 +00:00
func hash*(bid: BlockId): Hash =
hash(bid.root)
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
template root*(blck: BlockRef): Eth2Digest = blck.bid.root
template slot*(blck: BlockRef): Slot = blck.bid.slot
func init*(T: type BlockRef, root: Eth2Digest, slot: Slot): BlockRef =
BlockRef(
bid: BlockId(root: root, slot: slot)
)
Store finalized block roots in database (3s startup) (#3320) * Store finalized block roots in database (3s startup) When the chain has finalized a checkpoint, the history from that point onwards becomes linear - this is exploited in `.era` files to allow constant-time by-slot lookups. In the database, we can do the same by storing finalized block roots in a simple sparse table indexed by slot, bringing the two representations closer to each other in terms of conceptual layout and performance. Doing so has a number of interesting effects: * mainnet startup time is improved 3-5x (3s on my laptop) * the _first_ startup might take slightly longer as the new index is being built - ~10s on the same laptop * we no longer rely on the beacon block summaries to load the full dag - this is a lot faster because we no longer have to look up each block by parent root * a collateral benefit is that we no longer need to load the full summaries table into memory - we get the RSS benefits of #3164 without the CPU hit. Other random stuff: * simplify forky block generics * fix withManyWrites multiple evaluation * fix validator key cache not being updated properly in chaindag read-only mode * drop pre-altair summaries from `kvstore` * recreate missing summaries from altair+ blocks as well (in case database has lost some to an involuntary restart) * print database startup timings in chaindag load log * avoid allocating superfluos state at startup * use a recursive sql query to load the summaries of the unfinalized blocks
2022-01-30 16:51:04 +00:00
func init*(T: type BlockRef, root: Eth2Digest, blck: SomeForkyBeaconBlock):
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
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BlockRef =
BlockRef.init(root, blck.slot)
fix missing backfill when restarting node When node is restarted before backfill has started but after some blocks have finalized with forward sync, we would not start the backfill. * also clean up one last `SomeSome`
2022-02-11 15:58:33 +00:00
func toBlockId*(blck: SomeForkySignedBeaconBlock): BlockId =
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
BlockId(root: blck.root, slot: blck.message.slot)
func toBlockId*(blck: ForkedSignedBeaconBlock): BlockId =
withBlck(blck): BlockId(root: blck.root, slot: blck.message.slot)
func parent*(bs: BlockSlot): BlockSlot =
## Return a blockslot representing the previous slot, using the parent block
## if the current slot had a block
if bs.slot == Slot(0):
BlockSlot(blck: nil, slot: Slot(0))
else:
BlockSlot(
blck: if bs.slot > bs.blck.slot: bs.blck else: bs.blck.parent,
slot: bs.slot - 1
)
func parentOrSlot*(bs: BlockSlot): BlockSlot =
## Return a blockslot representing the previous slot, using the parent block
## with the current slot if the current had a block
if bs.blck.isNil():
BlockSlot(blck: nil, slot: Slot(0))
elif bs.slot == bs.blck.slot:
BlockSlot(blck: bs.blck.parent, slot: bs.slot)
else:
BlockSlot(blck: bs.blck, slot: bs.slot - 1)
func getDepth*(a, b: BlockRef): tuple[ancestor: bool, depth: int] =
var b = b
var depth = 0
const maxDepth = (100'i64 * 365 * 24 * 60 * 60 div SECONDS_PER_SLOT.int)
while true:
if a == b:
return (true, depth)
# for now, use an assert for block chain length since a chain this long
# indicates a circular reference here..
doAssert depth < maxDepth
depth += 1
if a.slot >= b.slot or b.parent.isNil:
return (false, depth)
doAssert b.slot > b.parent.slot
b = b.parent
func isAncestorOf*(a, b: BlockRef): bool =
let (isAncestor, _) = getDepth(a, b)
isAncestor
func link*(parent, child: BlockRef) =
use isZeroMemory for Eth2Digest comparisons (#3386) * use isZeroMemory for Eth2Digest comparisons * use Eth2Digest.isZero abstraction
2022-02-14 05:26:19 +00:00
doAssert (not (parent.root.isZero or child.root.isZero)),
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
"blocks missing root!"
doAssert parent.root != child.root, "self-references not allowed"
child.parent = parent
func get_ancestor*(blck: BlockRef, slot: Slot,
maxDepth = 100'i64 * 365 * 24 * 60 * 60 div SECONDS_PER_SLOT.int):
BlockRef =
automated CL spec ref URL updates from v1.1.9 to v1.1.10 (#3455)
2022-03-02 10:00:21 +00:00
## https://github.com/ethereum/consensus-specs/blob/v1.1.10/specs/phase0/fork-choice.md#get_ancestor
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
## Return the most recent block as of the time at `slot` that not more recent
## than `blck` itself
if isNil(blck): return nil
var blck = blck
var depth = 0
while true:
if blck.slot <= slot:
return blck
if isNil(blck.parent):
return nil
doAssert depth < maxDepth
depth += 1
blck = blck.parent
func atSlot*(blck: BlockRef, slot: Slot): BlockSlot =
## Return a BlockSlot at a given slot, with the block set to the closest block
## available. If slot comes from before the block, a suitable block ancestor
## will be used, else blck is returned as if all slots after it were empty.
## This helper is useful when imagining what the chain looked like at a
## particular moment in time, or when imagining what it will look like in the
## near future if nothing happens (such as when looking ahead for the next
## block proposal)
BlockSlot(blck: blck.get_ancestor(slot), slot: slot)
func atSlot*(blck: BlockRef): BlockSlot =
blck.atSlot(blck.slot)
func atSlot*(bid: BlockId, slot: Slot): BlockSlotId =
BlockSlotId(bid: bid, slot: slot)
func atSlot*(bid: BlockId): BlockSlotId =
bid.atSlot(bid.slot)
func atEpochStart*(blck: BlockRef, epoch: Epoch): BlockSlot =
## Return the BlockSlot corresponding to the first slot in the given epoch
time: spring cleaning (#3262) Time in the beacon chain is expressed relative to the genesis time - this PR creates a `beacon_time` module that collects helpers and utilities for dealing the time units - the new module does not deal with actual wall time (that's remains in `beacon_clock`). Collecting the time related stuff in one place makes it easier to find, avoids some circular imports and allows more easily identifying the code actually needs wall time to operate. * move genesis-time-related functionality into `spec/beacon_time` * avoid using `chronos.Duration` for time differences - it does not support negative values (such as when something happens earlier than it should) * saturate conversions between `FAR_FUTURE_XXX`, so as to avoid overflows * fix delay reporting in validator client so it uses the expected deadline of the slot, not "closest wall slot" * simplify looping over the slots of an epoch * `compute_start_slot_at_epoch` -> `start_slot` * `compute_epoch_at_slot` -> `epoch` A follow-up PR will (likely) introduce saturating arithmetic for the time units - this is merely code moves, renames and fixing of small bugs.
2022-01-11 10:01:54 +00:00
atSlot(blck, epoch.start_slot())
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
func atSlotEpoch*(blck: BlockRef, epoch: Epoch): BlockSlot =
## Return the last block that was included in the chain leading
## up to the given epoch - this amounts to the state at the time
## when epoch processing for `epoch` has been done, but no block
## has yet been applied
if epoch == GENESIS_EPOCH:
blck.atEpochStart(epoch)
else:
time: spring cleaning (#3262) Time in the beacon chain is expressed relative to the genesis time - this PR creates a `beacon_time` module that collects helpers and utilities for dealing the time units - the new module does not deal with actual wall time (that's remains in `beacon_clock`). Collecting the time related stuff in one place makes it easier to find, avoids some circular imports and allows more easily identifying the code actually needs wall time to operate. * move genesis-time-related functionality into `spec/beacon_time` * avoid using `chronos.Duration` for time differences - it does not support negative values (such as when something happens earlier than it should) * saturate conversions between `FAR_FUTURE_XXX`, so as to avoid overflows * fix delay reporting in validator client so it uses the expected deadline of the slot, not "closest wall slot" * simplify looping over the slots of an epoch * `compute_start_slot_at_epoch` -> `start_slot` * `compute_epoch_at_slot` -> `epoch` A follow-up PR will (likely) introduce saturating arithmetic for the time units - this is merely code moves, renames and fixing of small bugs.
2022-01-11 10:01:54 +00:00
let
start = epoch.start_slot()
tmp = blck.atSlot(start - 1)
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
if isNil(tmp.blck):
BlockSlot()
else:
tmp.blck.atSlot(start)
func toBlockSlotId*(bs: BlockSlot): BlockSlotId =
if isNil(bs.blck):
BlockSlotId()
else:
bs.blck.bid.atSlot(bs.slot)
func isProposed*(bid: BlockId, slot: Slot): bool =
## Return true if `bid` was proposed in the given slot
bid.slot == slot
func isProposed*(blck: BlockRef, slot: Slot): bool =
## Return true if `blck` was proposed in the given slot
Fix missing checkpoint states` (#3225) With the right sequence of events (for example a REST request or a validation), it can happen that the first traversal across a state checkpoint boundary is done without storing that state on disk - this causes problens when replaying states, because now states may be missing from the database. Here, we simply avoid using the caches when advancing a state that will go into the database, ensuring that the information lost during caching always is permanently stored. * fix recursion bug in `isProposed`
2021-12-30 11:33:03 +00:00
not isNil(blck) and blck.bid.isProposed(slot)
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
func isProposed*(bs: BlockSlot): bool =
## Return true if `bs` represents the proposed block (as opposed to an empty
## slot)
bs.blck.isProposed(bs.slot)
func isProposed*(bsi: BlockSlotId): bool =
## Return true if `bs` represents the proposed block (as opposed to an empty
## slot)
bsi.bid.isProposed(bsi.slot)
REST cleanups (#3255) * REST cleanups * reject out-of-range committee requests * print all hex values as lower-case * allow requesting state information by head state root * turn `DomainType` into array (follow spec) * `uint_to_bytesXX` -> `uint_to_bytes` (follow spec) * fix wrong dependent root in `/eth/v1/validator/duties/proposer/` * update documentation - `--subscribe-all-subnets` is no longer needed when using the REST interface with validator clients * more fixes * common helpers for dependent block * remove test rules obsoleted by more strict epoch tests * fix trailing commas * Update docs/the_nimbus_book/src/rest-api.md * Update docs/the_nimbus_book/src/rest-api.md Co-authored-by: sacha <sacha@status.im>
2022-01-08 20:06:34 +00:00
func dependentBlock*(head, tail: BlockRef, epoch: Epoch): BlockRef =
## The block that determined the proposer shuffling in the given epoch
let dependentSlot =
time: spring cleaning (#3262) Time in the beacon chain is expressed relative to the genesis time - this PR creates a `beacon_time` module that collects helpers and utilities for dealing the time units - the new module does not deal with actual wall time (that's remains in `beacon_clock`). Collecting the time related stuff in one place makes it easier to find, avoids some circular imports and allows more easily identifying the code actually needs wall time to operate. * move genesis-time-related functionality into `spec/beacon_time` * avoid using `chronos.Duration` for time differences - it does not support negative values (such as when something happens earlier than it should) * saturate conversions between `FAR_FUTURE_XXX`, so as to avoid overflows * fix delay reporting in validator client so it uses the expected deadline of the slot, not "closest wall slot" * simplify looping over the slots of an epoch * `compute_start_slot_at_epoch` -> `start_slot` * `compute_epoch_at_slot` -> `epoch` A follow-up PR will (likely) introduce saturating arithmetic for the time units - this is merely code moves, renames and fixing of small bugs.
2022-01-11 10:01:54 +00:00
if epoch >= Epoch(1): epoch.start_slot() - 1
REST cleanups (#3255) * REST cleanups * reject out-of-range committee requests * print all hex values as lower-case * allow requesting state information by head state root * turn `DomainType` into array (follow spec) * `uint_to_bytesXX` -> `uint_to_bytes` (follow spec) * fix wrong dependent root in `/eth/v1/validator/duties/proposer/` * update documentation - `--subscribe-all-subnets` is no longer needed when using the REST interface with validator clients * more fixes * common helpers for dependent block * remove test rules obsoleted by more strict epoch tests * fix trailing commas * Update docs/the_nimbus_book/src/rest-api.md * Update docs/the_nimbus_book/src/rest-api.md Co-authored-by: sacha <sacha@status.im>
2022-01-08 20:06:34 +00:00
else: Slot(0)
let res = head.atSlot(dependentSlot)
if isNil(res.blck): tail
else: res.blck
func prevDependentBlock*(head, tail: BlockRef, epoch: Epoch): BlockRef =
## The block that determined the attester shuffling in the given epoch
if epoch >= 1: head.dependentBlock(tail, epoch - 1)
else: head.dependentBlock(tail, epoch)
BlockId reform (#3176) * BlockId reform Introduce `BlockId` that helps track a root/slot pair - this prepares the codebase for backfilling and handling out-of-dag blocks * move block dag code to separate module * fix finalised state root in REST event stream * fix finalised head computation on head update, when starting from checkpoint * clean up chaindag init * revert `epochAncestor` change in introduced in #3144 that would return an epoch ancestor from the canoncial history instead of the given history, causing `EpochRef` keys to point to the wrong block
2021-12-09 17:06:21 +00:00
func shortLog*(v: BlockId): string =
# epoch:root when logging epoch, root:slot when logging slot!
shortLog(v.root) & ":" & $v.slot
func shortLog*(v: BlockSlotId): string =
# epoch:root when logging epoch, root:slot when logging slot!
if v.bid.slot == v.slot:
shortLog(v.bid)
else: # There was a gap - log it
shortLog(v.bid) & "@" & $v.slot
func shortLog*(v: BlockRef): string =
# epoch:root when logging epoch, root:slot when logging slot!
if v.isNil():
"nil:0"
else:
shortLog(v.bid)
func shortLog*(v: BlockSlot): string =
# epoch:root when logging epoch, root:slot when logging slot!
if isNil(v.blck):
"nil:0@" & $v.slot
elif v.blck.slot == v.slot:
shortLog(v.blck)
else: # There was a gap - log it
shortLog(v.blck) & "@" & $v.slot
chronicles.formatIt BlockId: shortLog(it)
chronicles.formatIt BlockSlotId: shortLog(it)
chronicles.formatIt BlockSlot: shortLog(it)
chronicles.formatIt BlockRef: shortLog(it)