nimbus-eth1/nimbus/db/core_db
Jordan Hrycaj d3d172edee
Replace `CoreDbRef` oo-methods by closures (#1668)
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
2023-08-02 21:46:41 +01:00
..
.gitignore Unified database frontend (#1661) 2023-07-31 14:43:38 +01:00
README.md Replace `CoreDbRef` oo-methods by closures (#1668) 2023-08-02 21:46:41 +01:00
base.nim Replace `CoreDbRef` oo-methods by closures (#1668) 2023-08-02 21:46:41 +01:00
core_apps.nim Unified database frontend (#1661) 2023-07-31 14:43:38 +01:00
legacy.nim Replace `CoreDbRef` oo-methods by closures (#1668) 2023-08-02 21:46:41 +01:00

README.md

Core database replacement wrapper object

This wrapper replaces the TrieDatabaseRef and its derivatives by the new object CoreDbRef.

Relations to current TrieDatabaseRef implementation

Here are some incomplete translations for objects and constructors.

Object types:

Legacy notation CoreDbRef based replacement
ChainDB (don't use/avoid)
ChainDbRef CoreDbRef
TrieDatabaseRef CoreDbKvtRef
HexaryTrie CoreDbMptRef
SecureHexaryTrie CoreDbPhkRef
DbTransaction CoreDbTxRef
TransactionID CoreDbTxID

Constructors:

Legacy notation CoreDbRef based replacement
trieDB newChainDB("..") newCoreDbRef(LegacyDbPersistent,"..")
newMemoryDB() newCoreDbRef(LegacyDbMemory)
--
initHexaryTrie(db,..) db.mpt(..) (no pruning)
db.mptPrune(..) (w/pruning true/false)
--
initSecureHexaryTrie(db,..) db.phk(..) (no pruning)
db.phkPrune(..) (w/pruning true/false)
--
newCaptureDB(db,memDB) db.capture() (see below)

Usage of the replacement wrapper

Objects pedigree:

    CoreDbRef                   -- base descriptor
     | | | |
     | | | +-- CoreDbMptRef     -- hexary trie instance
     | | | |    :                    :
     | | | +-- CoreDbMptRef     -- hexary trie instance
     | | |
     | | |
     | | +---- CoreDbPhkRef     -- pre-hashed key hexary trie instance
     | | |      :                    :
     | | +---- CoreDbPhkRef     -- pre-hashed key hexary trie instance
     | |
     | |
     | +------ CoreDbKvtRef     -- single static key-value table
     |
     |
     +-------- CoreDbCaptRef    -- tracer support descriptor

Instantiating standard database object descriptors works as follows:

    let
      db = newCoreDbRef(..)           # new base descriptor
      mpt = db.mpt(..)                # hexary trie/Merkle Patricia Tree
      phk = db.phk(..)                # pre-hashed key hexary trie/MPT
      kvt = db.kvt                    # key-value table

Tracer support setup by hiding the current CoreDbRef behind a replacement:

    let
      capture = db.capure()
      db = capture.recorder           # use the recorder in place of db
    ...

    for key,value in capture.recorder.kvt:
     ...                              # process recorded data