We know the aggregate publickey of a fully participating sync committee.
Because participation is typically very high (>95%), it is faster to
start from that aggregate publickey and subtract the individual keys of
non-participants, than summing up all the participating pubkeys.
Distinguish between those code locations that need to be updated on each
light client data format change, and those others that should generally
be fine, as long as a valid light client object is processed.
The former are tagged with static assert for `LightClientDataFork.high`.
The latter are changed to `lcDataFork > LightClientDataFork.None` to
indicate that they depend only on presence of any valid object.
Also bundled a few minor cleanups and fixes.
Also add `Forky` type for `LightClientStore` and minor fixes / cleanups.
The light client data structures were changed to accommodate additional
fields in future forks (e.g., to also hold execution data).
There is a minor change to the JSON serialization, where the `header`
properties are now nested inside a `LightClientHeader`.
The SSZ serialization remains compatible.
See https://github.com/ethereum/consensus-specs/pull/3190
and https://github.com/ethereum/beacon-APIs/pull/287
We currently use `BlockError` for both beacon blocks and LC objects.
In light of EIP4844, we will likely also use it for blob sidecars.
To avoid confusion, renaming it to a more generic `VerifierError`,
and update its documentation to be more generic.
To avoid long lines as a followup, also renaming the `block_processor`'s
`BlockProcessingCompleted.completed`->`ProcessingStatus.completed` and
`BlockProcessingCompleted.notCompleted`->`ProcessingStatus.notCompleted`
* SSZ `[]` -> `mitem`
* `[]` -> `item`
immutable access via mutable instance cannot rely on template
overloading, and `[]` cannot be a `func` because of special seq handling
in compiler.
Incorporates the latest changes to the light client sync protocol based
on Devconnect AMS feedback. Note that this breaks compatibility with the
previous prototype, due to changes to data structures and endpoints.
See https://github.com/ethereum/consensus-specs/pull/2802
Adds `LightClientProcessor` as the pendant to `BlockProcessor` while
operating in light client mode. Note that a similar mechanism based on
async futures is used for interoperability with existing infrastructure,
despite light client object validation being done synchronously.
When syncing as a light client, different behaviour is needed to handle
the various ways how errors may occur. The existing logic for blocks can
also be applied to light client objects:
- `Invalid`: Malformed object that is clearly an error by its producer.
- `MissingParent`: More data is needed to decide applicability.
- `UnviableFork`: Object may be valid but will never apply on this fork.
- `Duplicate`: No errors were encountered but the object was not useful.
This adopts the spec sections of the pre-release proposal of the libp2p
based light client sync protocol, and also adds a test runner for the
new accompanying tests. While the release version of the light client
sync protocol contains conflicting definitions, it is currently unused,
and the code specific to the pre-release proposal is marked as such.
See https://github.com/ethereum/consensus-specs/pull/2802
The spec does not provide code for validating the `fork_version` field
of `LightClientUpdate`. However, we can use our own logic for additional
validation of that field. The spec's python test suite sets up states
that do not follow the fork schedule (e.g., that use Altair fork version
before Altair fork epoch), which complicates upstreaming this as code.
Uses consistent formatting in `light_client_sync.nim`, always refers to
fork-dependent light client objects in full qualified notation, moves
`get_safety_threshold` helper function to same location as in the spec.
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.
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.
Etan Kissling
tersec
Jacek Sieka
Miran