* Aristo+Kvt: Fix backend `dup()` function in api setup
why:
Backend object is subject to an inheritance cascade which was not
taken care of, before. Only the base object was duplicated.
* Kvt: Simplify DB clone/peers management
* Aristo: Simplify DB clone/peers management
* Aristo: Adjust unit test for working with memory DB only
why:
This currently causes some memory corruption persumably in the
`libc` background layer.
* CoredDb+Kvt: Simplify API for KVT
why:
Simplified storage models (was over engineered) for better performance
and code maintenance.
* CoredDb+Aristo: Simplify API for `Aristo`
why:
Only single database state needed here. Accessing a similar state will
be implemented from outside this module using a context layer. This
gives better performance and improves code maintenance.
* Fix Copyright headers
* CoreDb: Turn off API tracking
why:
CI would ot go through. Was accidentally turned on.
* Aristo: Remove cruft
* Prettifying profile statistics printing & source code cosmetics
* Aristo/Kvt: API tools update
* CoreDb: Corrections, mostly API related
* CoreDb: Changed the tracer `logDb()` result
why:
Only the key-value table is used from the logger database
* CoreDb: Update legacy tracer
why:
The `contains()` directive did not correspond to `0 < get().len`
also:
Copy `CoreDb` meta settings like `trackLegaApi`, `trackNewApi`, etc. to
overlay tracer descriptor
* CoreDb: Extend/update tracer API
why:
Get ready for accommodating `Aristo` tracer
* Fix missing import
why:
Some CI compilers might have (cached?) a different NIM patch level
* Ditto
* Aristo/Kvt: Provide function hooks APIs
why:
These APIs can be used for installing tracers, profiling functoinality,
and other niceties on the databases.
* Aristo: Provide optional API profiling
details:
It basically is a re-implementation of the `CoreDb` profiling
implementation
* Kvt: Provide optional API profiling similar to `Aristo`
* CoreDb: Re-implementing profiling using `aristo_profile`
* Ledger: Re-implementing profiling using `aristo_profile`
* CoreDb: Update unit tests for maintainability
* update copyright dates
* Aristo: Update schedule runner for `hashify()`
why:
Width-first schedule walker overlooked resolvable vertex and ended in
a deadlock situation
* CoreDb+Aristo: Update error code for fringe condition
* Ledger: Remove redundant extra MPT hashing statements
why:
These statement were used for troubleshooting
* CoreDb: Couch medicine for legacy DB backend
why:
MPT will occasionally enter inconsistent states after deletion, some
dirty fix is randomly added to mitgate that.
* Added procs to get and store block witness in db and add generate-witness cli flag.
* Completed initial implementation of block witness storage.
* Added test to verify witness is persisted to db after call to persistBlock.
* Update getBlockWitness to return witness using Result type.
* Make generate witness parameter hidden.
* CoreDb: Test module with additional sample selector cmd line options
* Aristo: Do not automatically remove a storage trie with the account
why:
This is an unnecessary side effect. Rather than using an automatism, a
a storage root must be deleted manually.
* Aristo: Can handle stale storage root vertex IDs as empty IDs.
why:
This is currently needed for the ledger API supporting both, a legacy
and the `Aristo` database backend.
This feature can be disabled at compile time by re-setting the
`LOOSE_STORAGE_TRIE_COUPLING` flag in the `aristo_constants` module.
* CoreDb+Aristo: Flush/delete storage trie when deleting account
why:
On either backend, a deleted account leave a dangling storage trie on
the database.
For consistency nn the legacy backend, storage tries must not be
deleted as they might be shared by several accounts whereas on `Aristo`
they are always unique.
* Aristo: Update error return code
why:
Failing of `Aristo` function `delete()` might fail because there is
no such data item on the db. This must return a single error code
as is done with `fetch()`.
* Ledger: Better error handling
why:
The `expect()` clauses have been replaced by raising asserts indicating
the error from the database backend.
Also, `delete()` failures are legitimate if the item to delete does not
exist.
* Aristo: Delete function must always leave a label on DB for `hashify()`
why:
The `hashify()` uses the labels left bu `merge()` and `delete()` to
compile (and optimise) a scheduler for subsequent hashing.
Originally, the labels were not used for deleted entries and `delete()`
still had some edge case where the deletion label was not properly
handled.
* Aristo: Update `hashify()` scheduler, remove buggy optimisation
why:
Was left over from version without virtual state roots which did not
know about account payload leaf vertices referring to storage roots.
* Aristo: Label storage trie account in `delete()` similar to `merge()`
details;
The `delete()` function applied to a non-static state root (assumed
to be a storage root) will check the payload of an accounts leaf
and mark its Merkle keys to be re-checked when runninh `hashify()`
* Aristo: Clean up and re-org recycled vertex IDs in `hashify()`
why:
Re-organising the recycled vertex IDs list intends to reduce the size of the
list.
This list is organised as a LIFO (or stack.) By reorganising it in a way
so that the least vertex ID numbers are on top, the list will be kept
smaller as observed on some examples (less than 30%.)
* CoreDb: Accept storage trie deletion requests in non-initialised state
why:
Due to lazy initialisation, the root vertex ID might not yet exist. So
the `Aristo` database handlers would reject this call with an error and
this condition needs to be handled by the API (which realises the lazy
feature.)
* Cosmetics & code massage, prettify logging
* fix missing import
* CoreDb: Improve API and API tracking
why:
Now logs state roots where appropriate
* CoreDb: re-implement `CoreDbVidRef` => `CoreDbTrieRef`
why:
Instead of a root vertex ID wrapper, the purpose of this object type
has been upgrades to a sub-trie prototype.
caveat:
`Aristo` backend not fully functional, yet.
* CoreDb: Update `Aristo` backend
why:
Supports virtual sub-tries
* CoreDb: Account address tracking for `StorageTrie` virtual tries
details:
Supported with API tracking/logging
* CoreDb: Keep account address in payload object
why:
No need to provide extra address argument for `merge()`, also
provides tracking possibility for account debugging.
* Ledger: Update new API for `Aristo` specific storage trie handling
* CoreDb+Ledger: Update unit tests
* Fix copyright headers
* Aristo: Update unit test suite
* Aristo/Kvt: Fix iterators
why:
Generic iterators were not properly updated after backend change
* Aristo: Add sub-trie deletion functionality
why:
For storage tries linked to an account payload vertex ID, a the
whole storage trie needs to be deleted with the account.
* Aristo: Reserve vertex ID numbers for static custom state roots
why:
Static custom state roots may be controlled by an application,
e.g. for a receipt or a transaction root. The `Aristo` functions
are agnostic of what the static state roots are when different
from the internal tree vertex ID 1.
details;
The `merge()` function applied to a non-static state root (assumed
to be a storage root) will check the payload of an accounts leaf
and mark its Merkle keys to be re-checked.
* Aristo: Correct error code symbol
* Aristo: Update error code symbols
* Aristo: Code cosmetics/comments
* Aristo: Fix hashify schedule calculator
why:
Had a tendency to stop early leaving an incomplete job
* Aristo: Re-phrase `LayerDelta` and `LayerFinal` as object references
why:
Avoids copying in some cases
* Fix copyright header
* Aristo: Verify `leafTie.root` function argument for `merge()` proc
why:
Zero root will lead to inconsistent DB entry
* Aristo: Update failure condition for hash labels compiler `hashify()`
why:
Node need not be rejected as long as links are on the schedule. In
that case, `redo[]` is to become `wff.base[]` at a later stage.
This amends an earlier fix, part of #1952 by also testing against
the target nodes of the `wff.base[]` sets.
* Aristo: Add storage root glue record to `hashify()` schedule
why:
An account leaf node might refer to a non-resolvable storage root ID.
Storage root node chains will end up at the storage root. So the link
`storage-root->account-leaf` needs an extra item in the schedule.
* Aristo: fix error code returned by `fetchPayload()`
details:
Final error code is implied by the error code form the `hikeUp()`
function.
* CoreDb: Discard `createOk` argument in API `getRoot()` function
why:
Not needed for the legacy DB. For the `Arsto` DB, a lazy approach is
implemented where a stprage root node is created on-the-fly.
* CoreDb: Prevent `$$` logging in some cases
why:
Logging the function `$$` is not useful when it is used for internal
use, i.e. retrieving an an error text for logging.
* CoreDb: Add `tryHashFn()` to API for pretty printing
why:
Pretty printing must not change the hashification status for the
`Aristo` DB. So there is an independent API wrapper for getting the
node hash which never updated the hashes.
* CoreDb: Discard `update` argument in API `hash()` function
why:
When calling the API function `hash()`, the latest state is always
wanted. For a version that uses the current state as-is without checking,
the function `tryHash()` was added to the backend.
* CoreDb: Update opaque vertex ID objects for the `Aristo` backend
why:
For `Aristo`, vID objects encapsulate a numeric `VertexID`
referencing a vertex (rather than a node hash as used on the
legacy backend.) For storage sub-tries, there might be no initial
vertex known when the descriptor is created. So opaque vertex ID
objects are supported without a valid `VertexID` which will be
initalised on-the-fly when the first item is merged.
* CoreDb: Add pretty printer for opaque vertex ID objects
* Cosmetics, printing profiling data
* CoreDb: Fix segfault in `Aristo` backend when creating MPT descriptor
why:
Missing initialisation error
* CoreDb: Allow MPT to inherit shared context on `Aristo` backend
why:
Creates descriptors with different storage roots for the same
shared `Aristo` DB descriptor.
* Cosmetics, update diagnostic message items for `Aristo` backend
* Fix Copyright year
* Fix kvt headers
* Provide differential layers for KVT transaction stack
why:
Significant performance improvement
* Provide abstraction layer for database top cache layer
why:
This will eventually implemented as a differential database layers
or transaction layers. The latter is needed to improve performance.
behavioural changes:
Zero vertex and keys (i.e. delete requests) are not optimised out
until the last layer is written to the database.
* Provide differential layers for Aristo transaction stack
why:
Significant performance improvement
* Activate `LedgerRef` wrapper for `AccountsCache`
details:
`accounts_cache.nim` methods are indirectly processed by the wrapper
methods from `ledger.nim`.
This works for all sources except `test_state_db.nim` where the source
`accounts_cache.nim` is included (rather than imported) in order to
access objects privy to the very source.
* Provide facility to switch to a preselected `LedgerRef` type
details:
Can be set as suggestion when initialising `CommonRef`
* Update `CoreDb` test suite for better time tracking
details:
+ Allow time logging by pre-defined block intervals
+ Print `CoreDb`/`Ledger`profiling results (if enabled)
* Explicitly use shared `Kvt` table on `Ledger` and `Clique` lookup.
why:
Speeds up lookup time with `Aristo` backend. For writing `Clique` data,
the `Companion` model allows to write `Clique` data past the database
locked by evm transactions.
* Implement `CoreDb` profiling with API tracking
why:
Chasing time spent per APT procs ...
* Implement `Ledger` profiling with API tracking
why:
Chasing time spent per APT procs ...
* Always hashify when commiting or storing
why:
A dirty cache makes no sense when committing
* Make sure that a zero key is created when adding/updating vertices
why:
This is an error fix mainly for edge cases. A typical error was
that the root key got deleted when there were only a few vertices
left on the DB.
* Need all created and changed vertices zero-keyed on the cache
why:
A zero key (i.e. empty Merkle hash) indicates that a vertex key
needs to be updated. This would not be needed immediately after
a merge as there is an actual leaf path on the cache layer. But
after subsequent merge and delete operations this information
might get blurred.
* Re-org hashing algorithm
why:
Apart from errors, the previous implementation was too slow for
two reasons:
+ some control hashes were calculated for debugging (now all
verification is done in `aristo_check` module)
+ the leaf paths stored on the cache are used to build the
labelling (aka hashing) schedule; there paths were accumulated
over successive hash sessions although it is clear that all
keys were generated, already
* Fix copyright year
* Show elapsed times with enabled `CoreDb` API tracking
* Show elapsed times with enabled `LedgerRef` API tracking
* Reorg `CoreDb` auto destructors for `Aristo` DB
why:
While `Aristo` supports some parallelism for concurrent database access,
this comes with a price of management overhead. With a naive approach,
the auto-destructor will slow down execution because the ledger and
evm treat the database in a shared mode where a DB descriptor is just
created and thrown away shortly after.
This is reflected in the `Coredb` abstraction layer above `Aristo`/`Kvt`
where a few `Shared` type descriptors are cached and a shared reference
is returned rather than a disposable new object.
* For `CoreDb` support transaction level tracking
details:
This is mainly an extra for the legacy DB as `Aristo` and `Kvt` support
this already.
Also return an error on the legacy DB backend when `persistent()` is
called while there are transactions pending (the `persistent()` call
does nothing otherwise on the legacy backend.)
* Clear compiler warnings (remove unused variables etc.)
* Using different `tmp` directories for `Kvt` and `Aristo`
why:
Closing one database would leave the other set of directories
incomplete.
* Code cosmetics, silence compiler
* Fix typo `EMPTY_ROOT_HASH` vs. `EMPTY_CODE_HASH`
* Fix copyright years
* Split off `ReadOnlyStateDB` from `AccountStateDB` from `state_db.nim`
why:
Apart from testing, applications use `ReadOnlyStateDB` as an easy
way to access the accounts ledger. This is well supported by the
`Aristo` db, but writable mode is only parially supported.
The writable AccountStateDB` object for modifying accounts is not
used by production code.
So, for lecgacy and testing apps, the full support of the previous
`AccountStateDB` is now enabled by `import db/state_db/read_write`
and the `import db/state_db` provides read-only mode.
* Encapsulate `AccountStateDB` as `GenesisLedgerRef` or genesis creation
why:
`AccountStateDB` has poor support for `Aristo` and is not widely used
in favour of `AccountsLedger` (which will be abstracted as `ledger`.)
Currently, using other than the `AccountStateDB` ledgers within the
`GenesisLedgerRef` wrapper is experimental and test only. Eventually,
the wrapper should disappear so that the `Ledger` object (which
encapsulates `AccountsCache` and `AccountsLedger`) will prevail.
* For the `Ledger`, provide access to raw accounts `MPT`
why:
This gives to the `CoreDbMptRef` descriptor from the `CoreDb` (which is
the legacy version of CoreDxMptRef`.) For the new `ledger` API, the
accounts are based on the `CoreDxMAccRef` descriptor which uses a
particular sub-system for accounts while legacy applications use the
`CoreDbPhkRef` equivalent of the `SecureHexaryTrie`.
The only place where this feature will currently be used is the
`genesis.nim` source file.
* Fix `Aristo` bugs, missing boundary checks, typos, etc.
* Verify root vertex in `MPT` and account constructors
why:
Was missing so far, in particular the accounts constructor must
verify `VertexID(1)
* Fix include file
* Disable `TransactionID` related functions from `state_db.nim`
why:
Functions `getCommittedStorage()` and `updateOriginalRoot()` from
the `state_db` module are nowhere used. The emulation of a legacy
`TransactionID` type functionality is administratively expensive to
provide by `Aristo` (the legacy DB version is only partially
implemented, anyway).
As there is no other place where `TransactionID`s are used, they will
not be provided by the `Aristo` variant of the `CoreDb`. For the
legacy DB API, nothing will change.
* Fix copyright headers in source code
* Get rid of compiler warning
* Update Aristo code, remove unused `merge()` variant, export `hashify()`
why:
Adapt to upcoming `CoreDb` wrapper
* Remove synced tx feature from `Aristo`
why:
+ This feature allowed to synchronise transaction methods like begin,
commit, and rollback for a group of descriptors.
+ The feature is over engineered and not needed for `CoreDb`, neither
is it complete (some convergence features missing.)
* Add debugging helpers to `Kvt`
also:
Update database iterator, add count variable yield argument similar
to `Aristo`.
* Provide optional destructors for `CoreDb` API
why;
For the upcoming Aristo wrapper, this allows to control when certain
smart destruction and update can take place. The auto destructor works
fine in general when the storage/cache strategy is known and acceptable
when creating descriptors.
* Add update option for `CoreDb` API function `hash()`
why;
The hash function is typically used to get the state root of the MPT.
Due to lazy hashing, this might be not available on the `Aristo` DB.
So the `update` function asks for re-hashing the gurrent state changes
if needed.
* Update API tracking log mode: `info` => `debug
* Use shared `Kvt` descriptor in new Ledger API
why:
No need to create a new descriptor all the time
* Aristo: Provide key-value list signature calculator
detail:
Simple wrappers around `Aristo` core functionality
* Update new API for `CoreDb`
details:
+ Renamed new API functions `contains()` => `hasKey()` or `hasPath()`
which disables the `in` operator on non-boolean `contains()` functions
+ The functions `get()` and `fetch()` always return a not-found error if
there is no item, available. The new functions `getOrEmpty()` and
`mergeOrEmpty()` return an an empty `Blob` if there is no such key
found.
* Rewrite `core_apps.nim` using new API from `CoreDb`
* Use `Aristo` functionality for calculating Merkle signatures
details:
For debugging, the `VerifyAristoForMerkleRootCalc` can be set so
that `Aristo` results will be verified against the legacy versions.
* Provide general interface for Merkle signing key-value tables
details:
Export `Aristo` wrappers
* Activate `CoreDb` tests
why:
Now, API seems to be stable enough for general tests.
* Update `toHex()` usage
why:
Byteutils' `toHex()` is superior to `toSeq.mapIt(it.toHex(2)).join`
* Split `aristo_transcode` => `aristo_serialise` + `aristo_blobify`
why:
+ Different modules for different purposes
+ `aristo_serialise`: RLP encoding/decoding
+ `aristo_blobify`: Aristo database encoding/decoding
* Compacted representation of small nodes' links instead of Keccak hashes
why:
Ethereum MPTs use Keccak hashes as node links if the size of an RLP
encoded node is at least 32 bytes. Otherwise, the RLP encoded node
value is used as a pseudo node link (rather than a hash.) Such a node
is nor stored on key-value database. Rather the RLP encoded node value
is stored instead of a lode link in a parent node instead. Only for
the root hash, the top level node is always referred to by the hash.
This feature needed an abstraction of the `HashKey` object which is now
either a hash or a blob of length at most 31 bytes. This leaves two
ways of representing an empty/void `HashKey` type, either as an empty
blob of zero length, or the hash of an empty blob.
* Update `CoreDb` interface (mainly reducing logger noise)
* Fix copyright years (to make `Lint` happy)
* Make sure that storage tries are not pruned (by default) on the new Ledger API
why:
Pruning might kill some unwanted entries from storage tries ending up with an unstable database
leading to crashes.
* Implement `CoreDb` and `LedgerRef` API tracing
details:
+ Locally enabled at compile time via constants `ProvideCoreDbLegacyAPI`
and `EnableApiTracking` in either `base.nim` source
+ If enabled it can be selectively turned on/off via public switches in
the `CoreDb` descriptor.
* Allow suppressing opportunistic `ifNecessaryGetXxx()` functions
why:
Better troubleshooting when the system crashes (assertions will then
most probably happen outside an `async` function.)
* Provide TDD/debug facility for inspecting `persistBlocks()` working
detail:
+ Make sure that the last block of a test sample is the first batch
item in `persistBlocks()`.
+ Additionally, allow `AccountsCache` API tracing by setting the flag
`extraTraceMessages = true` in the file `accounts_cache.nim`
* Overload AccountsCache by abstraction wrapper
details:
Can facilitate CoreDb API switch, details in `ledger/README.md`.
* CoreDB: Re-org API
details:
Legacy API internally uses vertex ID for root node abstraction
* Cosmetics: Move some unit test helpers to common sub-directory
* Extract constant from `accouns_cache.nim` => `constants.nim`
* Fix tracer methods
why:
Logger dump data were wrongly dumped from the production database. This
caused an assert exception when iterating over the persistent database
(instead of the memory logger.) This event in turn was enabled after
fixing another inconsistency which just set up an empty iterator. Unit
tests failed to detect that.
* Split `core_db/base.nim` into several sources
* Rename `core_db/legacy.nim` => `core_db/legacy_db.nim`
* Update `CoreDb` API, dual methods returning `Result[]` or plain value
detail:
Plain value methods implemet the legacy API, they defect on error results
* Redesign `CoreDB` direct backend access
why:
Made the `backend` directive integral part of the API
* Discontinue providing unused or otherwise available functions
details:
+ setTransactionID() removed, not used and not easily replicable in Aristo
+ maybeGet() removed, available via direct backend access
+ newPhk() removed, never used & was experimental anyway
* Update/reorg backend API
why:
+ Added error print function `$$()`
+ General descriptor completion (and optional validation) via `bless()`
* Update `Aristo`/`Kvt` exception handling
why:
Avoid `CatchableError` exceptions, rather pass them as error code where
appropriate.
* More `CoreDB` compliant `Aristo` and `Kvt` methods
details:
+ Providing functions like `contains()`, `getVtxRc()` (returns `Result[]`).
+ Additional error code: `NotImplemented`
* Rewrite/reorg of Aristo DB constructor
why:
Previously used global object `DefaultQidLayoutRef` as default
initialiser. This object was created at compile time which lead to
non-gc safe functions.
* Update nimbus/db/core_db/legacy_db.nim
Co-authored-by: Kim De Mey <kim.demey@gmail.com>
* Update nimbus/db/aristo/aristo_transcode.nim
Co-authored-by: Kim De Mey <kim.demey@gmail.com>
* Update nimbus/db/core_db/legacy_db.nim
Co-authored-by: Kim De Mey <kim.demey@gmail.com>
---------
Co-authored-by: Kim De Mey <kim.demey@gmail.com>
* Kvt: Implemented multi-descriptor access on the same backend
why:
This behaviour mirrors the one of Aristo and can be used for
simultaneous transactions on Aristo + Kvt
* Kvt: Update database iterators
why:
Forgot to run on the top layer first
* Kvt: Misc fixes
* Aristo, use `openArray[byte]` rather than `Blob` in prototype
* Aristo, by default hashify right after cloning descriptor
why:
Typically, a completed descriptor is expected after cloning. Hashing
can be suppressed by argument flag.
* Aristo provides `replicate()` iterator, similar to legacy `replicate()`
* Aristo API fixes and updates
* CoreDB: Rename `legacy_persistent` => `legacy_rocksdb`
why:
More systematic, will be in line with Aristo DB which might have
more than one persistent backends
* CoreDB: Prettify API sources
why:
Better to read and maintain
details:
Annotating with custom pragmas which cleans up the prototypes
* CoreDB: Update MPT/put() prototype allowing `CatchableError`
why:
Will be needed for Aristo API (legacy is OK with `RlpError`)
* Nimbus folder environment update
details:
* Integrated `CoreDbRef` for the sources in the `nimbus` sub-folder.
* The `nimbus` program does not compile yet as it needs the updates
in the parallel `stateless` sub-folder.
* Stateless environment update
details:
* Integrated `CoreDbRef` for the sources in the `stateless` sub-folder.
* The `nimbus` program compiles now.
* Premix environment update
details:
* Integrated `CoreDbRef` for the sources in the `premix` sub-folder.
* Fluffy environment update
details:
* Integrated `CoreDbRef` for the sources in the `fluffy` sub-folder.
* Tools environment update
details:
* Integrated `CoreDbRef` for the sources in the `tools` sub-folder.
* Nodocker environment update
details:
* Integrated `CoreDbRef` for the sources in the
`hive_integration/nodocker` sub-folder.
* Tests environment update
details:
* Integrated `CoreDbRef` for the sources in the `tests` sub-folder.
* The unit tests compile and run cleanly now.
* Generalise `CoreDbRef` to any `select_backend` supported database
why:
Generalisation was just missed due to overcoming some compiler oddity
which was tied to rocksdb for testing.
* Suppress compiler warning for `newChainDB()`
why:
Warning was added to this function which must be wrapped so that
any `CatchableError` is re-raised as `Defect`.
* Split off persistent `CoreDbRef` constructor into separate file
why:
This allows to compile a memory only database version without linking
the backend library.
* Use memory `CoreDbRef` database by default
detail:
Persistent DB constructor needs to import `db/core_db/persistent
why:
Most tests use memory DB anyway. This avoids linking `-lrocksdb` or
any other backend by default.
* fix `toLegacyBackend()` availability check
why:
got garbled after memory/persistent split.
* Clarify raw access to MPT for snap sync handler
why:
Logically, `kvt` is not the raw access for the hexary trie (although
this holds for the legacy database)
why:
* Resolves some compiler coughing when it bails out on persitent
db constructor inside `test()` caluses (works perfectly outside.)
* API looks cleaner and better to maintain for the price of slightly
more work at the backend
* Remove 32bit os support from `custom_network` unit test
also:
* Fix compilation annoyance #1648
* Fix unit test on Kiln (changed `merge` logic?)
* Hide unused sources do not compile
why:
* Get them out of the way before major update
* Import and function prototype mismatch -- maybe some changes got out
of scope.
* Re-implemented `db_chain` as `core_db`
why:
Hiding `TrieDatabaseRef` and `HexaryTrie` by default allows to replace
the current db wrapper by some other one, e.g. Aristo
* Support compiler exception warnings for CoreDbRef base methods.
* Allow `pairs()` iterator on all memory based key-value tables
why:
Previously only available for capture recorder.
* Backport `chain_db.nim` changes into its re-implementation `core_apps.nim`
* Fix exception annotation
Jordan Hrycaj
web3-developer
andri lim
Kim De Mey