It's sometimes useful to simulate what happens when a chain runs from a
given state with a given set of private keys - `wss_sim` allows running
such a simulation.
One use of such a tool is to simulate a weak subjectivity attack,
creating alternative histories of the same chain:
https://notes.status.im/nimbus-insecura-network#
* limit by-root requests to non-finalized blocks
Presently, we keep a mapping from block root to `BlockRef` in memory -
this has simplified reasoning about the dag, but is not sustainable with
the chain growing.
We can distinguish between two cases where by-root access is useful:
* unfinalized blocks - this is where the beacon chain is operating
generally, by validating incoming data as interesting for future fork
choice decisions - bounded by the length of the unfinalized period
* finalized blocks - historical access in the REST API etc - no bounds,
really
In this PR, we limit the by-root block index to the first use case:
finalized chain data can more efficiently be addressed by slot number.
Future work includes:
* limiting the `BlockRef` horizon in general - each instance is 40
bytes+overhead which adds up - this needs further refactoring to deal
with the tail vs state problem
* persisting the finalized slot-to-hash index - this one also keeps
growing unbounded (albeit slowly)
Anyway, this PR easily shaves ~128mb of memory usage at the time of
writing.
* No longer honor `BeaconBlocksByRoot` requests outside of the
non-finalized period - previously, Nimbus would generously return any
block through this libp2p request - per the spec, finalized blocks
should be fetched via `BeaconBlocksByRange` instead.
* return `Opt[BlockRef]` instead of `nil` when blocks can't be found -
this becomes a lot more common now and thus deserves more attention
* `dag.blocks` -> `dag.forkBlocks` - this index only carries unfinalized
blocks from now - `finalizedBlocks` covers the other `BlockRef`
instances
* in backfill, verify that the last backfilled block leads back to
genesis, or panic
* add backfill timings to log
* fix missing check that `BlockRef` block can be fetched with
`getForkedBlock` reliably
* shortcut doppelganger check when feature is not enabled
* in REST/JSON-RPC, fetch blocks without involving `BlockRef`
* fix dag.blocks ref
* initial support for minification and new interchange tests. Removal of v1 and v1 migration.
* Synthetic attestations: SQLite3 requires one statement/query per prepared statement
* Fix DB import interrupted if no attestation was found
* Skip test relying on undocumented test behavior (https://github.com/eth-clients/slashing-protection-interchange-tests/pull/12#issuecomment-1011158701)
* Skip test relying on unclear minification behavior:
creating an invalid minified attestation with source > target or setting target = max(source, target)
* remove DB v1 and update submodule
* Apply suggestions from code review
Co-authored-by: Jacek Sieka <jacek@status.im>
Co-authored-by: Jacek Sieka <jacek@status.im>
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.
* Harden CommitteeIndex, SubnetId, SyncSubcommitteeIndex
Harden the use of `CommitteeIndex` et al to prevent future issues by
using a distinct type, then validating before use in several cases -
datatypes in spec are kept simple though so that invalid data still can
be read.
* fix invalid epoch used in REST
`/eth/v1/beacon/states/{state_id}/committees` committee length (could
return invalid data)
* normalize some variable names
* normalize committee index loops
* fix `RestAttesterDuty` to use `uint64` for `validator_committee_index`
* validate `CommitteeIndex` on ingress in REST API
* update rest rules with stricter parsing
* better REST serializers
* save lots of memory by not using `zip` ...at least a few bytes!
* 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>
Overhaul of era files, including documentation and reference
implementations
* store blocks, then state, then slot indices for easy lookup at low
cost
* document era file rationale
* altair+ support in era writer
* support downloading blocks / states via JSON in addition to SSZ -
slow, but needed for infura support - SSZ is still used when server
supports it
* use common forked block/state reader in REST API
* fix stack overflows in REST JSON decoder
* fix invalid serialization of `justification_bits` in
`/eth/v1/debug/beacon/states` and `/eth/v2/debug/beacon/states`
* fix REST client to use `/eth/...` instead of `/api/eth/...`, update
"default" urls to expose REST api via `/eth` as well as this is what the
standard says - `/api` was added early on based on an example "base url"
in the spec that has been removed since
* expose Nimbus REST extensions via `/nimbus` in addition to
`/api/nimbus` to stay consistent with `/eth`
* fix invalid state root when reading states via REST
* fix recursive imports in `spec/ssz_codec`
* remove usages of `serialization.useCustomSerialization` - fickle
With checkpoint sync in particular, and state pruning in the future,
loading states or state-dependent data may fail. This PR adjusts the
code to allow this to be handled gracefully.
In particular, the new availability assumption is that states are always
available for the finalized checkpoint and newer, but may fail for
anything older.
The `tail` remains the point where state loading de-facto fails, meaning
that between the tail and the finalized checkpoint, we can still get
historical data (but code should be prepared to handle this as an
error).
However, to harden the code against long replays, several operations
which are assumed to work only with non-final data (such as gossip
verification and validator duties) now limit their search horizon to
post-finalized data.
* harden several state-dependent operations by logging an error instead
of introducing a panic when state loading fails
* `withState` -> `withUpdatedState` to differentiate from the other
`withState`
* `updateStateData` can now fail if no state is found in database - it
is also hardened against excessively long replays
* `getEpochRef` can now fail when replay fails
* reject blocks with invalid target root - they would be ignored
previously
* fix recursion bug in `isProposed`
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`
* use v1.1.6 test vectors; use BeaconTime instead of Slot in fork choice
* tick through every slot at least once
* use div INTERVALS_PER_SLOT and use precomputed constants of them
* use correct (even if numerically equal) constant
Introduced in #3171, it turns out we can just follow the block headers
to achieve the same effect
* leaves the constant in the code so as to avoid confusion when reading
database that had the constant written (such as the fleet nodes and
other unstable users)
Validator monitoring based on and mostly compatible with the
implementation in Lighthouse - tracks additional logs and metrics for
specified validators so as to stay on top on performance.
The implementation works more or less the following way:
* Validator pubkeys are singled out for monitoring - these can be
running on the node or not
* For every action that the validator takes, we record steps in the
process such as messages being seen on the network or published in the
API
* When the dust settles at the end of an epoch, we report the
information from one epoch before that, which coincides with the
balances being updated - this is a tradeoff between being correct
(waiting for finalization) and providing relevant information in a
timely manner)
* SyncManager cleanups for backfill support
Cleanups, fixes and simplifications, in anticipation of backfill support
for the `SyncManager`:
* reformat sync progress indicator to show time left and % done more
prominently:
* old: `sync="sPssPsssss:2:2.4229:00h57m (2706898)"`
* new: `sync="14d12h31m (0.52%) 1.1378slots/s (wQQQQQDDQQ:1287520)"`
* reset average speed when going out of sync
* pass all block errors to sync manager, including duplicate/unviable
* penalize peers for reporting a head block that is outside of our
expected wall clock time (they're likely on a different network or
trying to disrupt sync)
* remove `SyncFailureKind` (unused)
* remove `inRange` (unused)
* add `Q` for sync queue requests that are in the `SyncQueue` but not
yet in the `BlockProcessor` queue
* update last slot in `SyncQueue` after getting peer status
* fix race condition between `wakeupWaiters` and `resetWait`, where
workers would not be correctly reset if block verification returned a
completed future without event loop
* log syncmanager direction
* Fix ordering issue.
Some of the requests size of which are not equal to `chunkSize` could be processed in wrong order which could lead to sync process freezes.
Co-authored-by: cheatfate <eugene.kabanov@status.im>
In the ChainDAG, 3 block pointers are kept: genesis, tail and head. This
PR adds one more block pointer: the backfill block which represents the
block that has been backfilled so far.
When doing a checkpoint sync, a random block is given as starting point
- this is the tail block, and we require that the tail block has a
corresponding state.
When backfilling, we end up with blocks without corresponding states,
hence we cannot use `tail` as a backfill pointer - there is no state.
Nonetheless, we need to keep track of where we are in the backfill
process between restarts, such that we can answer GetBeaconBlocksByRange
requests.
This PR adds the basic support for backfill handling - it needs to be
integrated with backfill sync, and the REST API needs to be adjusted to
take advantage of the new backfilled blocks when responding to certain
requests.
Future work will also enable moving the tail in either direction:
* pruning means moving the tail forward in time and removing states
* backwards means recreating past states from genesis, such that
intermediate states are recreated step by step all the way to the tail -
at that point, tail, genesis and backfill will match up.
* backfilling is done when backfill != genesis - later, this will be the
WSS checkpoint instead
As of https://github.com/status-im/nim-eth/pull/379 `nim-eth` defines a
couple static test cases for merkle proof verification.
Since the EF has defined a `is_valid_merkle_branch` function in the spec
we are no longer using the custom implementation from `nim-eth`, but the
tests were never ported to target the new implementation. This patch now
follows up on that and integrates those tests from `nim-eth`.
* 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
In #780 a test was disabled that verified that an attestation with
empty `aggregation_bits` completes successfully. The test was never
re-introduced, and as of the current consensus spec v1.1.6, such
attestations are not considered valid, as they fail the check in
`is_valid_indexed_attestation`. This patch fully removes that outdated
test, and moves it to the list of pending invalid attestation tests.
* batch-verify sync messages for a small perf boost
Generally reuses the same structure as attestation and aggregate
verification
* normalize `signatures` and `signature_batch` to use the same pattern
of verification
* normalize parameter names, order etc for signature stuff in general
* avoid calling `blsSign` directly - instead, go through `signatures`
consistently
* Introduce slot->BlockRef mapping for finalized chain
The finalized chain is linear, thus we can use a seq to lookup blocks by
slot number.
Here, we introduce such a seq, even though in the future, it should
likely be backed by a database structure instead, or, more likely, a
flat era file with a flat lookup index.
This dramatically speeds up requests by slot, such as those coming from
the REST interface or GetBlocksByRange, as these are currently served by
a linear iteration from head.
* fix REST block requests to not return blocks from an earlier slot when
the given slot is empty
* fix StateId interpretation such that it doesn't treat state roots as
block roots
* don't load full block from database just to return its root
* move quarantine outside of chaindag
The quarantine has been part of the ChainDAG for the longest time, but
this design has a few issues:
* the function in which blocks are verified and added to the dag becomes
reentrant and therefore difficult to reason about - we're currently
using a stateful flag to work around it
* quarantined blocks bypass the processing queue leading to a processing
stampede
* the quarantine flow is unsuitable for orphaned attestations - these
should also should be quarantined eventually
Instead of processing the quarantine inside ChainDAG, this PR moves
re-queueing to `block_processor` which already is responsible for
dealing with follow-up work when a block is added to the dag
This sets the stage for keeping attestations in the quarantine as well.
Also:
* make `BlockError` `{.pure.}`
* avoid use of `ValidationResult` in block clearance (that's for gossip)
This extends the `makeTestBlocks` function used in tests with a new
parameter `syncCommitteeRatio` to control whether the produced blocks
should be signed by the validators assigned to the sync committee.
A similar parameter already exists to configure whether attestations
for the test blocks should be produced.
* add EF fork choice tests to CI
* checkpoints
* compilation fixes and add test to preset dependent suite
* support longpaths on Windows CI
* skip minimal tests (long paths issue + impl detals tested)
* fix stackoverflow on some platforms
* rebase on top of https://github.com/status-im/nimbus-eth2/pull/3054
* fix stack usage
Renames and cleanups split out from the validator monitoring branch, so
as to reduce conflict area vs other PR:s
* add constants for expected message timing
* name validators after the messages they validate, mostly, to make
grepping easier
* unify field naming of EpochInfo across forks to make cross-fork code
easier
* ncli_db: add putState, putBlock
These tools allow modifying an existing nimbus database for the purpose
of recovery or reorg, moving the head, tail and genesis to arbitrary
points.
* remove potentially expensive `putState` in `BeaconStateDB`
* introduce `latest_block_root` which computes the root of the latest
applied block from the `latest_block_header` field (instead of passing
it in separately)
* avoid some unnecessary BeaconState copies during init
* discover https://github.com/nim-lang/Nim/issues/19094
* prefer `HashedBeaconState` in a few places to avoid recomputing state
root
* fetch latest block root from state when creating blocks
* harden `get_beacon_proposer_index` against invalid slots and document
* move random spec function tests to `test_spec.nim`
* avoid unnecessary state root computation before block proposal
* Support starting from altair
* hide `finalized-checkpoint-` - they are incomplete and usage may cause
crashes
* remove genesis detection code (broken, obsolete)
* enable starting ChainDAG from altair checkpoints - this is a
prerequisite for checkpoint sync (TODO: backfill)
* tighten checkpoint state conditions
* show error when starting from checkpoint with existing database (not
supported)
* print rest-compatible JSON in ncli/state_sim
* altair/merge support in ncli
* more altair/merge support in ncli_db
* pre-load header to speed up loading
* fix forked block decoding
* fix stack overflow crash in REST/debug/getStateV2
* introduce `ForkyXxx` for generic type matching of `Xxx` across
branches (SomeHashedBeaconState -> ForkyHashedBeaconState et al) -
`Some` is already used for other types of type classes
* consolidate function naming in BeaconChainDB, use some generics
* import `forks.nim` from other spec modules and move `Forked*` helpers
around to resolve circular imports
* remove `ForkedBeaconState`, use `ForkedHashedBeaconState` throughout
(less data shuffling between the types)
* fix several cases of states being stored on stack in tests, causing
random failures on some platforms
* remove reading json support from ncli - this should be ported to the
rest json reading instead (doesn't currently work because stack sizes)
The sync committee period used to be a plain `uint64`. With the light
client sync relying more heavily on them, it makes sense to introduce
a proper type for them, similar to how they are already used for `Slot`
and `Epoch`. This introduces such a `SyncCommitteePeriod` type.
Furthermore, some usage code dealing with those periods is cleaned up.
* Logging and startup improvements
Color support for released binaries!
* startup scripts no longer log to file by default - this only affects
source builds - released binaries don't support file logging
* add --log-stdout option to control logging to stdout (colors, json)
* detect tty:s vs redirected logs and log accordingly
* add option to disable log colors at runtime
* simplify several "common" logs, showing the most important information
earlier and more clearly
* remove line numbers / file information / tid - these take up space and
are of little use to end users
* still enabled in debug builds and tools
* remove `testnet_servers_image` compile-time option
* server images, released binaries and compile-from-source now offer
the same behaviour and features
* fixes https://github.com/status-im/nimbus-eth2/issues/2326
* fixes https://github.com/status-im/nimbus-eth2/issues/1794
* remove instanteneous block speed from sync message, keeping only
average
before:
```
INF 2021-10-28 16:45:59.000+02:00 Slot start topics="beacnde" tid=386429 file=nimbus_beacon_node.nim:884 lastSlot=2384027 wallSlot=2384028 delay=461us84ns peers=0 head=75a10ee5:3348 headEpoch=104 finalized=cd6804ba:3264 finalizedEpoch=102 sync="wwwwwwwwww:0:0.0000:0.0000:00h00m (3348)"
INF 2021-10-28 16:45:59.046+02:00 Slot end topics="beacnde" tid=386429 file=nimbus_beacon_node.nim:821 slot=2384028 nextSlot=2384029 head=75a10ee5:3348 headEpoch=104 finalizedHead=cd6804ba:3264 finalizedEpoch=102 nextAttestationSlot=-1 nextProposalSlot=-1 nextActionWait=n/a
```
after:
```
INF 2021-10-28 22:43:23.033+02:00 Slot start topics="beacnde" slot=2385815 epoch=74556 sync="DDPDDPUDDD:10:5.2258:01h19m (2361088)" peers=37 head=eacd2dae:2361096 finalized=73782:a4751487 delay=33ms687us715ns
INF 2021-10-28 22:43:23.291+02:00 Slot end topics="beacnde" slot=2385815 nextActionWait=n/a nextAttestationSlot=-1 nextProposalSlot=-1 head=eacd2dae:2361096
```
* fix comment
* documentation updates
* mention `--log-file` may be deprecated in the future
* update various docs
Updated the local network simulation scripts to use the REST interface
for connecting the validator client to the beacon node. Otherwise, the
current scripts produce errors.
* `SyncCommitteeIndex` -> `SyncSubcommitteeIndex`
* `syncCommitteePeriod` -> `sync_committee_period` (spec spelling)
* tighten period comparisons
* fix assert when validating committee message with non-altair state in
REST api
* register vc duties with subnet tracker
* fix activation logging during startup
* cache slot signature to avoid duplicate signature work
* schedule aggregation duties one slot at a time to avoid CPU spike at
each epoch
* lower aggregation subnet pre-subscription time to 4 slots (lowers
bandwidth and CPU usage)
* update stability subnets in ENR on startup
* log gossip state
* perform gossip subscriptions just before the next slot starts
* document stuff
* add random include
* don't overwrite subscription state when not subscribed
* log target gossip state
* updating gossip status once is enough
* add test
* remove syncQueueLen - this one is not updated at the end of the sync
and may cause gossip to disconnect itself completely - use a simple head
distance instead
* fix gossip disconnection - if in hysteresis, node.gossipState will be
set to disabled even though we don't disable topic subscriptions
* fix extra duty registration call
Similar to the existing `RewardInfo`, this PR adds the infrastructure
needed to export epoch processing information from altair+. Because
accounting is done somewhat differently, the PR uses a fork-specific
object to extrct the information in order to make the cost on the spec
side low.
* RewardInfo -> EpochInfo, ForkedEpochInfo
* use array for computing new sync committee
* avoid repeated total active balance computations in block processing
* simplify proposer index check
* simplify epoch transition tests
* pre-compute base increment and reuse in epoch processing, and a few
other small optimizations
This PR introduces the type and does the heavy lifting in terms of
refactoring - the tools that use the accounting will need separate PR:s
(as well as refinements to the exportred information)
* "official" -> "scenarios", like the submodule
* fewer test binaries - various compile hacks have been improved over
time, test suite should follow
* remove obsolete bls tests - there are better test vectors in
nim-blscurve
* remove obsolete mentions of `ssz_testing`
* remove obsolete comments about proc vs globals, unittest2 already uses
proc's
This extends `mock_blocks` support to also allow producing Merge blocks.
The only step missing was initialization of the `ExecutionPayload` to an
empty value (as created by `build_empty_execution_payload`).
So far, `withState` and `withBlck` templates could only be used to have
convenience access to fork-agnostic BeaconState and BeaconBlock fields.
This patch:
- injects an additional `stateFork` constant that allows to use
`when` expressions to also access Altair and Merge-specific fields.
- introduces a `withStateAndBlck` template to support operating on both
a `BeaconState` and `BeaconBlock` at a time.
- makes sync committee related functions Merge aware.
- changes a couple if-else trees for forks into case statements so that
forgotten future forks are promoted to compile-time errors.
So far, SSZ tests for `uint128` and `uint256` integers were disabled
due to "compile-time issues". The code has been adjusted to support
those additional test vectors, and the corresponding tests have been
enabled.
In tests, the private key was put into the validator deposit's withdraw
credentials so that it can be recovered later. This leads to problems
when creating the validators through other means that do not put the key
there. In general, mock private keys only depend on the validator index,
though, and because it is clear what the index of a validator is, it is
not actually needed to put the key into the credentials.
There are a number of locations in the code that get attestations on a
forked beacon state. For attestation pools test, a convenience wrapper
was available to reduce clutter. This patch integrates that wrapper into
the core component so that it can also take advantage of the wrapper.
Replaced non-conventional `-Present` form in copyright headers with the
more appropriate `-2021` version that is already used by the majority of
the code base. Copyright header should indicate the years during which
the specific file was modified.
There are multiple ways how states can be processed during tests. One is
through tests/mocking, the other through tests/xxxutil. Both methods can
create genesis states with a set of deposits from mock validators. The
private keys for those validators are created differently, though. While
tests/mocking generates random keys, testblockutil generates fixed keys.
This is a problem when mixing both tests/mocking and testblockutil in a
single test case, as they assume that the deposits were generated using
the same method. This patch aligns the key generation across tests.
The initialization of a `SyncAggregate` to its default value is not very
intuitive. There is an `init` function in `sync_committee_msg_pool` that
provides a convenience wrapper. This patch exports that initializer so
that the rest of the code base can also take advantage of it.
Adds a function that constructs a Merkle proof for a generalized index.
This will be used during light client sync to update light clients with
a new state (see NEXT_SYNC_COMMITTEE_INDEX / FINALIZED_ROOT_INDEX).
The phase0 and altair overloads of `makeBeaconBlock` slightly differ in
their signatures which makes using them unnecessarily verbose.
- A placeholder `sync_aggregate` argument similar to `executionPayload`
is added to the phase0 overload to match the altair signature.
- A wrapper operating on `ForkedHashedBeaconState` is introduced.
When sync committee message handling was introduced in #2830, the edge
case of the same validator being selected multiple times as part of a
sync subcommittee was not covered. Not handling that edge case makes
sync contributions have a lower-than-expected participation rate as each
sync validator is only counted up through once per subcommittee.
This patch ensures that this edge case is properly covered.
testblockutil currently fails to add test blocks to Altair state because
it assumes phase0 blocks in various places. This patch corrects this
limitation by using forked types internally. Note that existing clients
so far solely operate on phase0 blocks and should eventually be updated.
* Add parallel attestation verification
* Update tests, batchVerify doesn't use the threadpool with only single core (nim-blscurve update)
* bump nim-blscurve
* Debug info for failing eth2 test vectors
* remove submodule eth2-testnets
* verbose debugging of make failure on Windows (libbacktrace?)
* Remove CI debug mode
* initialization convention
* Fix new altair tests
When creating beacon blocks, the state needs to be advanced to the new
slot to determine the correct proposer index. In #875 a regression got
introduced that removed this logic when mocking blocks. Existing tests
failed to detect this, as they do not make use of the proposer index.
This patch re-introduces the state advancement, fixing the problem.
Currently, only the function to mock a block at next slot is exported.
A more generic function that allows specifying any slot is available but
not exported. This patch marks that function to also be exported.
The mocking framework was limited to chain configurations that do not
include Altair at genesis. This patch extends it so that genesis states
can be generated that are already upgraded to Altair. This is useful for
tests such as eth2spec/test/altair/unittests/test_sync_protocol.py.
The `initGenesisState` function to mock genesis states for testing was
originally introduced with a `genesis_time` parameter in #326. However,
this parameter was never respected and genesis state was always mocked
with `genesis_time` assumed to be 0. Since there is no test overriding
`genesis_time`, the parameter is removed until needed.
* add merge SSZ consensus object tests
* add merge attestations, attester slashing, proposer slashing, and voluntary exit test fixtures
* throw catchable exception rather than assert on invalid SingleMemberUnion selector
* hash_tree_root can assert, because it's trusted data by that point
* re-assert on writing, since also trusted data
* beta.4 update
* implement upgrade_to_merge()
Other changes:
* Add server getBlockV2(), and produceBlockV2().
* Add getBlockV2() to REST test suite.
* Add client getBlockV2(), and produceBlockV2().
* Fix URLs in comments.
* Add some primitives and fix some issues in forks.nim.
* Switch `validator_client` to V2 calls usage.
* Bump `chronos` with imports fixes.
* Bump `nim-json-serialization` for `requireAllFields`.
tersec
Jacek Sieka
Mamy Ratsimbazafy
Zahary Karadjov
Etan Kissling
Eugene Kabanov
kdeme
Tanguy