class AccountDB(BaseAccountDB):
logger = logging.getLogger('evm.db.account.AccountDB')
def __init__(self, db, state_root=BLANK_ROOT_HASH):
r"""
Internal implementation details (subject to rapid change):
Database entries go through several pipes, like so...
.. code::
-> hash-trie -> storage lookups
/
db -----------------------> _journaldb ----------------> code lookups
\
> _trie -> _trie_cache -> _journaltrie --------------> account lookups
Journaling sequesters writes here ^, until persist is called.
_journaldb is a journaling of the keys and values used to store
code and account storage.
_trie is a hash-trie, used to generate the state root
_trie_cache is a cache tied to the state root of the trie. It
is important that this cache is checked *after* looking for
the key in _journaltrie, because the cache is only invalidated
after a state root change.
_journaltrie is a journaling of the accounts (an address->rlp mapping,
rather than the nodes stored by the trie). This enables
a squashing of all account changes before pushing them into the trie.
.. NOTE:: There is an opportunity to do something similar for storage
AccountDB synchronizes the snapshot/revert/persist of both of the
journals.
"""
self._journaldb = JournalDB(db)
self._trie = HashTrie(HexaryTrie(db, state_root))
self._trie_cache = CacheDB(self._trie)
self._journaltrie = JournalDB(self._trie_cache)
@property
def state_root(self):
return self._trie.root_hash
@state_root.setter
def state_root(self, value):
self._trie_cache.reset_cache()
self._trie.root_hash = value
#
# Storage
#
def get_storage(self, address, slot):
validate_canonical_address(address, title="Storage Address")
validate_uint256(slot, title="Storage Slot")
account = self._get_account(address)
storage = HashTrie(HexaryTrie(self._journaldb, account.storage_root))
slot_as_key = pad32(int_to_big_endian(slot))
if slot_as_key in storage:
encoded_value = storage[slot_as_key]
return rlp.decode(encoded_value, sedes=rlp.sedes.big_endian_int)
else:
return 0
def set_storage(self, address, slot, value):
validate_uint256(value, title="Storage Value")
validate_uint256(slot, title="Storage Slot")
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
storage = HashTrie(HexaryTrie(self._journaldb, account.storage_root))
slot_as_key = pad32(int_to_big_endian(slot))
if value:
encoded_value = rlp.encode(value)
storage[slot_as_key] = encoded_value
else:
del storage[slot_as_key]
self._set_account(address,
account.copy(storage_root=storage.root_hash))
def delete_storage(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
self._set_account(address, account.copy(storage_root=BLANK_ROOT_HASH))
#
# Balance
#
def get_balance(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
return account.balance
def set_balance(self, address, balance):
validate_canonical_address(address, title="Storage Address")
validate_uint256(balance, title="Account Balance")
account = self._get_account(address)
self._set_account(address, account.copy(balance=balance))
#
# Nonce
#
def get_nonce(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
return account.nonce
def set_nonce(self, address, nonce):
validate_canonical_address(address, title="Storage Address")
validate_uint256(nonce, title="Nonce")
account = self._get_account(address)
self._set_account(address, account.copy(nonce=nonce))
def increment_nonce(self, address):
current_nonce = self.get_nonce(address)
self.set_nonce(address, current_nonce + 1)
#
# Code
#
def get_code(self, address):
validate_canonical_address(address, title="Storage Address")
try:
return self._journaldb[self.get_code_hash(address)]
except KeyError:
return b""
def set_code(self, address, code):
validate_canonical_address(address, title="Storage Address")
validate_is_bytes(code, title="Code")
account = self._get_account(address)
code_hash = keccak(code)
self._journaldb[code_hash] = code
self._set_account(address, account.copy(code_hash=code_hash))
def get_code_hash(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
return account.code_hash
def delete_code(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
self._set_account(address, account.copy(code_hash=EMPTY_SHA3))
#
# Account Methods
#
def account_has_code_or_nonce(self, address):
return self.get_nonce(address) != 0 or self.get_code_hash(
address) != EMPTY_SHA3
def delete_account(self, address):
validate_canonical_address(address, title="Storage Address")
del self._journaltrie[address]
def account_exists(self, address):
validate_canonical_address(address, title="Storage Address")
return self._journaltrie.get(address, b'') != b''
def touch_account(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
self._set_account(address, account)
def account_is_empty(self, address):
return not self.account_has_code_or_nonce(
address) and self.get_balance(address) == 0
#
# Internal
#
def _get_account(self, address):
rlp_account = self._journaltrie.get(address, b'')
if rlp_account:
account = rlp.decode(rlp_account, sedes=Account)
else:
account = Account()
return account
def _set_account(self, address, account):
rlp_account = rlp.encode(account, sedes=Account)
self._journaltrie[address] = rlp_account
#
# Record and discard API
#
def record(self) -> Tuple[UUID, UUID]:
return (self._journaldb.record(), self._journaltrie.record())
def discard(self, changeset: Tuple[UUID, UUID]) -> None:
db_changeset, trie_changeset = changeset
self._journaldb.discard(db_changeset)
self._journaltrie.discard(trie_changeset)
def commit(self, changeset: Tuple[UUID, UUID]) -> None:
db_changeset, trie_changeset = changeset
self._journaldb.commit(db_changeset)
self._journaltrie.commit(trie_changeset)
def persist(self) -> None:
self.logger.debug("Persisting AccountDB...")
self._journaldb.persist()
self._journaltrie.persist()
def _log_pending_accounts(self) -> None:
accounts_displayed = set() # type: Set[bytes]
queued_changes = self._journaltrie.journal.journal_data.items()
# mypy bug for ordered dict reversibility: https://github.com/python/typeshed/issues/2078
for checkpoint, accounts in reversed(queued_changes): # type: ignore
for address in accounts:
if address in accounts_displayed:
continue
else:
accounts_displayed.add(address)
account = self._get_account(address)
self.logger.debug(
"Account %s: balance %d, nonce %d, storage root %s, code hash %s",
encode_hex(address),
account.balance,
account.nonce,
encode_hex(account.storage_root),
encode_hex(account.code_hash),
)
class ChainDB(BaseChainDB):
def __init__(self, db, trie_class=HexaryTrie):
self.db = JournalDB(db)
self.set_trie(trie_class)
#
# Canonical chain API
#
def get_canonical_head(self):
if not self.exists(CANONICAL_HEAD_HASH_DB_KEY):
raise CanonicalHeadNotFound("No canonical head set for this chain")
return self.get_block_header_by_hash(self.db.get(CANONICAL_HEAD_HASH_DB_KEY))
def get_canonical_block_header_by_number(self, block_number):
"""
Returns the block header with the given number in the canonical chain.
Raises BlockNotFound if there's no block header with the given number in the
canonical chain.
"""
validate_uint256(block_number, title="Block Number")
return self.get_block_header_by_hash(self.lookup_block_hash(block_number))
#
# Block Header API
#
def get_block_header_by_hash(self, block_hash):
"""
Returns the requested block header as specified by block hash.
Raises BlockNotFound if it is not present in the db.
"""
validate_word(block_hash, title="Block Hash")
try:
block = self.db.get(block_hash)
except KeyError:
raise BlockNotFound("No block with hash {0} found".format(
encode_hex(block_hash)))
return rlp.decode(block, sedes=BlockHeader)
def header_exists(self, block_hash):
"""Returns True if the header with the given block hash is in our DB."""
return self.db.exists(block_hash)
# TODO: This method sould take a chain of headers as that's the most common use case
# and it'd be much faster than inserting each header individually.
def persist_header_to_db(self, header):
"""
:returns: iterable of headers newly on the canonical chain
"""
if header.parent_hash != GENESIS_PARENT_HASH and not self.header_exists(header.parent_hash):
raise ParentNotFound(
"Cannot persist block header ({}) with unknown parent ({})".format(
encode_hex(header.hash), encode_hex(header.parent_hash)))
self.db.set(
header.hash,
rlp.encode(header),
)
if header.parent_hash == GENESIS_PARENT_HASH:
score = header.difficulty
else:
score = self.get_score(header.parent_hash) + header.difficulty
self.db.set(
make_block_hash_to_score_lookup_key(header.hash),
rlp.encode(score, sedes=rlp.sedes.big_endian_int))
try:
head_score = self.get_score(self.get_canonical_head().hash)
except CanonicalHeadNotFound:
new_headers = self._set_as_canonical_chain_head(header)
else:
if score > head_score:
new_headers = self._set_as_canonical_chain_head(header)
else:
new_headers = []
return new_headers
def _set_as_canonical_chain_head(self, header):
"""
:returns: iterable of headers newly on the canonical head
"""
try:
self.get_block_header_by_hash(header.hash)
except BlockNotFound:
raise ValueError("Cannot use unknown block hash as canonical head: {}".format(
header.hash))
new_canonical_headers = tuple(reversed(self._find_new_ancestors(header)))
# remove transaction lookups for blocks that are no longer canonical
for h in new_canonical_headers:
try:
old_hash = self.lookup_block_hash(h.block_number)
except KeyError:
# no old block, and no more possible
break
else:
old_header = self.get_block_header_by_hash(old_hash)
for transaction_hash in self.get_block_transaction_hashes(old_header):
self._remove_transaction_from_canonical_chain(transaction_hash)
# TODO re-add txn to internal pending pool (only if local sender)
pass
for h in new_canonical_headers:
self._add_block_number_to_hash_lookup(h)
self.db.set(CANONICAL_HEAD_HASH_DB_KEY, header.hash)
return new_canonical_headers
@to_tuple
def _find_new_ancestors(self, header):
"""
Returns the chain leading up from the given header until (but not including)
the first ancestor it has in common with our canonical chain.
If D is the canonical head in the following chain, and F is the new header,
then this function returns (F, E).
A - B - C - D
\
E - F
"""
h = header
while True:
try:
orig = self.get_canonical_block_header_by_number(h.block_number)
except KeyError:
# This just means the block is not on the canonical chain.
pass
else:
if orig.hash == h.hash:
# Found the common ancestor, stop.
break
# Found a new ancestor
yield h
if h.parent_hash == GENESIS_PARENT_HASH:
break
else:
h = self.get_block_header_by_hash(h.parent_hash)
def _add_block_number_to_hash_lookup(self, header):
block_number_to_hash_key = make_block_number_to_hash_lookup_key(
header.block_number
)
self.db.set(
block_number_to_hash_key,
rlp.encode(header.hash, sedes=rlp.sedes.binary),
)
#
# Block API
#
def get_score(self, block_hash):
return rlp.decode(
self.db.get(make_block_hash_to_score_lookup_key(block_hash)),
sedes=rlp.sedes.big_endian_int)
def lookup_block_hash(self, block_number):
"""
Return the block hash for the given block number.
"""
validate_uint256(block_number, title="Block Number")
number_to_hash_key = make_block_number_to_hash_lookup_key(block_number)
return rlp.decode(
self.db.get(number_to_hash_key),
sedes=rlp.sedes.binary,
)
def persist_block_to_db(self, block):
'''
Chain must do follow-up work to persist transactions to db
'''
new_canonical_headers = self.persist_header_to_db(block.header)
# Persist the transaction bodies
transaction_db = self.trie_class(self.db, root_hash=self.empty_root_hash)
for i, transaction in enumerate(block.transactions):
index_key = rlp.encode(i, sedes=rlp.sedes.big_endian_int)
transaction_db[index_key] = rlp.encode(transaction)
assert transaction_db.root_hash == block.header.transaction_root
for header in new_canonical_headers:
for index, transaction_hash in enumerate(self.get_block_transaction_hashes(header)):
self._add_transaction_to_canonical_chain(transaction_hash, header, index)
# Persist the uncles list
self.db.set(
block.header.uncles_hash,
rlp.encode(block.uncles, sedes=rlp.sedes.CountableList(type(block.header))),
)
def get_block_uncles(self, uncles_hash):
validate_word(uncles_hash, title="Uncles Hash")
return rlp.decode(self.db.get(uncles_hash), sedes=rlp.sedes.CountableList(BlockHeader))
#
# Transaction and Receipt API
#
@to_list
def get_receipts(self, header, receipt_class):
receipt_db = self.trie_class(db=self.db, root_hash=header.receipt_root)
for receipt_idx in itertools.count():
receipt_key = rlp.encode(receipt_idx)
if receipt_key in receipt_db:
receipt_data = receipt_db[receipt_key]
yield rlp.decode(receipt_data, sedes=receipt_class)
else:
break
def _get_block_transaction_data(self, block_header):
'''
:returns: iterable of encoded transactions for the given block header
'''
transaction_db = self.trie_class(self.db, root_hash=block_header.transaction_root)
for transaction_idx in itertools.count():
transaction_key = rlp.encode(transaction_idx)
if transaction_key in transaction_db:
yield transaction_db[transaction_key]
else:
break
@to_list
def get_block_transaction_hashes(self, block_header):
for encoded_transaction in self._get_block_transaction_data(block_header):
yield keccak(encoded_transaction)
@to_list
def get_block_transactions(self, block_header, transaction_class):
for encoded_transaction in self._get_block_transaction_data(block_header):
yield rlp.decode(encoded_transaction, sedes=transaction_class)
def get_transaction_by_index(self, block_number, transaction_index, transaction_class):
try:
block_header = self.get_canonical_block_header_by_number(block_number)
except KeyError:
raise TransactionNotFound("Block {} is not in the canonical chain".format(block_number))
transaction_db = self.trie_class(self.db, root_hash=block_header.transaction_root)
encoded_index = rlp.encode(transaction_index)
if encoded_index in transaction_db:
encoded_transaction = transaction_db[encoded_index]
return rlp.decode(encoded_transaction, sedes=transaction_class)
else:
raise TransactionNotFound(
"No transaction is at index {} of block {}".format(transaction_index, block_number))
def get_pending_transaction(self, transaction_hash, transaction_class):
try:
data = self.db.get(make_transaction_hash_to_data_lookup_key(transaction_hash))
return rlp.decode(data, sedes=transaction_class)
except KeyError:
raise TransactionNotFound(
"Transaction with hash {} not found".format(encode_hex(transaction_hash)))
def get_transaction_index(self, transaction_hash):
try:
encoded_key = self.db.get(make_transaction_hash_to_block_lookup_key(transaction_hash))
except KeyError:
raise TransactionNotFound(
"Transaction {} not found in canonical chain".format(encode_hex(transaction_hash)))
transaction_key = rlp.decode(encoded_key, sedes=TransactionKey)
return (transaction_key.block_number, transaction_key.index)
def _remove_transaction_from_canonical_chain(self, transaction_hash):
self.db.delete(make_transaction_hash_to_block_lookup_key(transaction_hash))
def _add_transaction_to_canonical_chain(self, transaction_hash, block_header, index):
"""
:param bytes transaction_hash: the hash of the transaction to add the lookup for
:param block_header: The header of the block with the txn that is in the canonical chain
:param int index: the position of the transaction in the block
- add lookup from transaction hash to the block number and index that the body is stored at
- remove transaction hash to body lookup in the pending pool
"""
transaction_key = TransactionKey(block_header.block_number, index)
self.db.set(
make_transaction_hash_to_block_lookup_key(transaction_hash),
rlp.encode(transaction_key),
)
# because transaction is now in canonical chain, can now remove from pending txn lookups
lookup_key = make_transaction_hash_to_data_lookup_key(transaction_hash)
if self.db.exists(lookup_key):
self.db.delete(lookup_key)
def add_pending_transaction(self, transaction):
self.db.set(
make_transaction_hash_to_data_lookup_key(transaction.hash),
rlp.encode(transaction),
)
def add_transaction(self, block_header, index_key, transaction):
transaction_db = self.trie_class(self.db, root_hash=block_header.transaction_root)
transaction_db[index_key] = rlp.encode(transaction)
return transaction_db.root_hash
def add_receipt(self, block_header, index_key, receipt):
receipt_db = self.trie_class(db=self.db, root_hash=block_header.receipt_root)
receipt_db[index_key] = rlp.encode(receipt)
return receipt_db.root_hash
#
# Raw Database API
#
def exists(self, key):
return self.db.exists(key)
def persist_trie_data_dict_to_db(self, trie_data_dict):
"""
Store raw trie data to db from a dict
"""
for key, value in trie_data_dict.items():
self.db[key] = value
#
# Snapshot and revert API
#
def snapshot(self):
return self.db.snapshot()
def revert(self, checkpoint):
self.db.revert(checkpoint)
def commit(self, checkpoint):
self.db.commit(checkpoint)
def clear(self):
self.db.clear()
#
# State Database API
#
def get_state_db(self, state_root, read_only):
return AccountStateDB(db=self.db, root_hash=state_root, read_only=read_only)
class AccountDB(BaseAccountDB):
def __init__(self, db, state_root=BLANK_ROOT_HASH):
# Keep a reference to the original db instance to use it as part of _get_account()'s cache
# key.
self._unwrapped_db = db
self.db = JournalDB(db)
self._trie = HashTrie(HexaryTrie(self.db, state_root))
@property
def state_root(self):
return self._trie.root_hash
@state_root.setter
def state_root(self, value):
self._trie.root_hash = value
#
# Storage
#
def get_storage(self, address, slot):
validate_canonical_address(address, title="Storage Address")
validate_uint256(slot, title="Storage Slot")
account = self._get_account(address)
storage = HashTrie(HexaryTrie(self.db, account.storage_root))
slot_as_key = pad32(int_to_big_endian(slot))
if slot_as_key in storage:
encoded_value = storage[slot_as_key]
return rlp.decode(encoded_value, sedes=rlp.sedes.big_endian_int)
else:
return 0
def set_storage(self, address, slot, value):
validate_uint256(value, title="Storage Value")
validate_uint256(slot, title="Storage Slot")
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
storage = HashTrie(HexaryTrie(self.db, account.storage_root))
slot_as_key = pad32(int_to_big_endian(slot))
if value:
encoded_value = rlp.encode(value)
storage[slot_as_key] = encoded_value
else:
del storage[slot_as_key]
self._set_account(address,
account.copy(storage_root=storage.root_hash))
def delete_storage(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
self._set_account(address, account.copy(storage_root=BLANK_ROOT_HASH))
#
# Balance
#
def get_balance(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
return account.balance
def set_balance(self, address, balance):
validate_canonical_address(address, title="Storage Address")
validate_uint256(balance, title="Account Balance")
account = self._get_account(address)
self._set_account(address, account.copy(balance=balance))
#
# Nonce
#
def get_nonce(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
return account.nonce
def set_nonce(self, address, nonce):
validate_canonical_address(address, title="Storage Address")
validate_uint256(nonce, title="Nonce")
account = self._get_account(address)
self._set_account(address, account.copy(nonce=nonce))
def increment_nonce(self, address):
current_nonce = self.get_nonce(address)
self.set_nonce(address, current_nonce + 1)
#
# Code
#
def get_code(self, address):
validate_canonical_address(address, title="Storage Address")
try:
return self.db[self.get_code_hash(address)]
except KeyError:
return b""
def set_code(self, address, code):
validate_canonical_address(address, title="Storage Address")
validate_is_bytes(code, title="Code")
account = self._get_account(address)
code_hash = keccak(code)
self.db[code_hash] = code
self._set_account(address, account.copy(code_hash=code_hash))
def get_code_hash(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
return account.code_hash
def delete_code(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
self._set_account(address, account.copy(code_hash=EMPTY_SHA3))
#
# Account Methods
#
def account_has_code_or_nonce(self, address):
return self.get_nonce(address) != 0 or self.get_code_hash(
address) != EMPTY_SHA3
def delete_account(self, address):
validate_canonical_address(address, title="Storage Address")
del self._trie[address]
def account_exists(self, address):
validate_canonical_address(address, title="Storage Address")
return bool(self._trie[address])
def touch_account(self, address):
validate_canonical_address(address, title="Storage Address")
account = self._get_account(address)
self._set_account(address, account)
def account_is_empty(self, address):
return not self.account_has_code_or_nonce(
address) and self.get_balance(address) == 0
#
# Internal
#
def _get_account(self, address):
cache_key = (id(self._unwrapped_db), self.state_root, address)
if cache_key not in account_cache:
account_cache[cache_key] = self._trie[address]
rlp_account = account_cache[cache_key]
if rlp_account:
account = rlp.decode(rlp_account, sedes=Account)
else:
account = Account()
return account
def _set_account(self, address, account):
rlp_account = rlp.encode(account, sedes=Account)
self._trie[address] = rlp_account
cache_key = (id(self._unwrapped_db), self.state_root, address)
account_cache[cache_key] = rlp_account
#
# Record and discard API
#
def record(self) -> UUID:
return self.db.record()
def discard(self, changeset_id: UUID) -> None:
return self.db.discard(changeset_id)
def commit(self, changeset_id: UUID) -> None:
return self.db.commit(changeset_id)
def persist(self) -> None:
return self.db.persist()
def clear(self) -> None:
return self.db.reset()
class BaseChainDB:
def __init__(self, db):
self.db = JournalDB(db)
def exists(self, key):
return self.db.exists(key)
def get_canonical_head(self):
if not self.exists(CANONICAL_HEAD_HASH_DB_KEY):
raise CanonicalHeadNotFound("No canonical head set for this chain")
return self.get_block_header_by_hash(
self.db.get(CANONICAL_HEAD_HASH_DB_KEY))
def get_canonical_block_header_by_number(self, block_number):
"""
Returns the block header with the given number in the canonical chain.
Raises BlockNotFound if there's no block header with the given number in the
canonical chain.
"""
validate_uint256(block_number, title="Block Number")
return self.get_block_header_by_hash(
self.lookup_block_hash(block_number))
def get_score(self, block_hash):
return rlp.decode(self.db.get(
make_block_hash_to_score_lookup_key(block_hash)),
sedes=rlp.sedes.big_endian_int)
def _set_as_canonical_chain_head(self, header):
"""
:returns: iterable of headers newly on the canonical head
"""
try:
self.get_block_header_by_hash(header.hash)
except BlockNotFound:
raise ValueError(
"Cannot use unknown block hash as canonical head: {}".format(
header.hash))
new_canonical_headers = tuple(
reversed(self._find_new_ancestors(header)))
# remove transaction lookups for blocks that are no longer canonical
for h in new_canonical_headers:
try:
old_hash = self.lookup_block_hash(h.block_number)
except KeyError:
# no old block, and no more possible
break
else:
old_header = self.get_block_header_by_hash(old_hash)
for transaction_hash in self.get_block_transaction_hashes(
old_header):
self._remove_transaction_from_canonical_chain(
transaction_hash)
# TODO re-add txn to internal pending pool (only if local sender)
pass
for h in new_canonical_headers:
self.add_block_number_to_hash_lookup(h)
self.db.set(CANONICAL_HEAD_HASH_DB_KEY, header.hash)
return new_canonical_headers
@to_tuple
def _find_new_ancestors(self, header):
"""
Returns the chain leading up from the given header until (but not including)
the first ancestor it has in common with our canonical chain.
If D is the canonical head in the following chain, and F is the new header,
then this function returns (F, E).
A - B - C - D
\
E - F
"""
h = header
while True:
try:
orig = self.get_canonical_block_header_by_number(
h.block_number)
except KeyError:
# This just means the block is not on the canonical chain.
pass
else:
if orig.hash == h.hash:
# Found the common ancestor, stop.
break
# Found a new ancestor
yield h
if h.parent_hash == GENESIS_PARENT_HASH:
break
else:
h = self.get_block_header_by_hash(h.parent_hash)
def get_block_header_by_hash(self, block_hash):
"""
Returns the requested block header as specified by block hash.
Raises BlockNotFound if it is not present in the db.
"""
validate_word(block_hash, title="Block Hash")
try:
block = self.db.get(block_hash)
except KeyError:
raise BlockNotFound("No block with hash {0} found".format(
encode_hex(block_hash)))
return rlp.decode(block, sedes=BlockHeader)
def header_exists(self, block_hash):
"""Returns True if the header with the given block hash is in our DB."""
return self.db.exists(block_hash)
def lookup_block_hash(self, block_number):
"""
Return the block hash for the given block number.
"""
validate_uint256(block_number, title="Block Number")
number_to_hash_key = make_block_number_to_hash_lookup_key(block_number)
return rlp.decode(
self.db.get(number_to_hash_key),
sedes=rlp.sedes.binary,
)
def get_block_uncles(self, uncles_hash):
validate_word(uncles_hash, title="Uncles Hash")
return rlp.decode(self.db.get(uncles_hash),
sedes=rlp.sedes.CountableList(BlockHeader))
@to_list
def get_receipts(self, header, receipt_class):
receipt_db = HexaryTrie(db=self.db, root_hash=header.receipt_root)
for receipt_idx in itertools.count():
receipt_key = rlp.encode(receipt_idx)
if receipt_key in receipt_db:
receipt_data = receipt_db[receipt_key]
yield rlp.decode(receipt_data, sedes=receipt_class)
else:
break
def _get_block_transaction_data(self, block_header):
'''
:returns: iterable of encoded transactions for the given block header
'''
transaction_db = HexaryTrie(self.db,
root_hash=block_header.transaction_root)
for transaction_idx in itertools.count():
transaction_key = rlp.encode(transaction_idx)
if transaction_key in transaction_db:
yield transaction_db[transaction_key]
else:
break
@to_list
def get_block_transaction_hashes(self, block_header):
for encoded_transaction in self._get_block_transaction_data(
block_header):
yield keccak(encoded_transaction)
@to_list
def get_block_transactions(self, block_header, transaction_class):
for encoded_transaction in self._get_block_transaction_data(
block_header):
yield rlp.decode(encoded_transaction, sedes=transaction_class)
def get_transaction_by_index(self, block_number, transaction_index,
transaction_class):
try:
block_header = self.get_canonical_block_header_by_number(
block_number)
except KeyError:
raise TransactionNotFound(
"Block {} is not in the canonical chain".format(block_number))
transaction_db = HexaryTrie(self.db,
root_hash=block_header.transaction_root)
encoded_index = rlp.encode(transaction_index)
if encoded_index in transaction_db:
encoded_transaction = transaction_db[encoded_index]
return rlp.decode(encoded_transaction, sedes=transaction_class)
else:
raise TransactionNotFound(
"No transaction is at index {} of block {}".format(
transaction_index, block_number))
def get_pending_transaction(self, transaction_hash, transaction_class):
try:
data = self.db.get(
make_transaction_hash_to_data_lookup_key(transaction_hash))
return rlp.decode(data, sedes=transaction_class)
except KeyError:
raise TransactionNotFound(
"Transaction with hash {} not found".format(
encode_hex(transaction_hash)))
def get_transaction_index(self, transaction_hash):
try:
encoded_key = self.db.get(
make_transaction_hash_to_block_lookup_key(transaction_hash))
except KeyError:
raise TransactionNotFound(
"Transaction {} not found in canonical chain".format(
encode_hex(transaction_hash)))
transaction_key = rlp.decode(encoded_key, sedes=TransactionKey)
return (transaction_key.block_number, transaction_key.index)
def add_block_number_to_hash_lookup(self, header):
block_number_to_hash_key = make_block_number_to_hash_lookup_key(
header.block_number)
self.db.set(
block_number_to_hash_key,
rlp.encode(header.hash, sedes=rlp.sedes.binary),
)
# TODO: This method sould take a chain of headers as that's the most common use case
# and it'd be much faster than inserting each header individually.
def persist_header_to_db(self, header):
"""
:returns: iterable of headers newly on the canonical chain
"""
if header.parent_hash != GENESIS_PARENT_HASH and not self.header_exists(
header.parent_hash):
raise ParentNotFound(
"Cannot persist block header ({}) with unknown parent ({})".
format(encode_hex(header.hash),
encode_hex(header.parent_hash)))
self.db.set(
header.hash,
rlp.encode(header),
)
if header.parent_hash == GENESIS_PARENT_HASH:
score = header.difficulty
else:
score = self.get_score(header.parent_hash) + header.difficulty
self.db.set(make_block_hash_to_score_lookup_key(header.hash),
rlp.encode(score, sedes=rlp.sedes.big_endian_int))
try:
head_score = self.get_score(self.get_canonical_head().hash)
except CanonicalHeadNotFound:
new_headers = self._set_as_canonical_chain_head(header)
else:
if score > head_score:
new_headers = self._set_as_canonical_chain_head(header)
else:
new_headers = []
return new_headers
def persist_block_to_db(self, block):
'''
Chain must do follow-up work to persist transactions to db
'''
new_canonical_headers = self.persist_header_to_db(block.header)
# Persist the transaction bodies
transaction_db = HexaryTrie(self.db, root_hash=BLANK_ROOT_HASH)
for i, transaction in enumerate(block.transactions):
index_key = rlp.encode(i, sedes=rlp.sedes.big_endian_int)
transaction_db[index_key] = rlp.encode(transaction)
assert transaction_db.root_hash == block.header.transaction_root
for header in new_canonical_headers:
for index, transaction_hash in enumerate(
self.get_block_transaction_hashes(header)):
self._add_transaction_to_canonical_chain(
transaction_hash, header, index)
# Persist the uncles list
self.db.set(
block.header.uncles_hash,
rlp.encode(block.uncles,
sedes=rlp.sedes.CountableList(type(block.header))),
)
def _remove_transaction_from_canonical_chain(self, transaction_hash):
self.db.delete(
make_transaction_hash_to_block_lookup_key(transaction_hash))
def _add_transaction_to_canonical_chain(self, transaction_hash,
block_header, index):
"""
:param bytes transaction_hash: the hash of the transaction to add the lookup for
:param block_header: The header of the block with the txn that is in the canonical chain
:param int index: the position of the transaction in the block
- add lookup from transaction hash to the block number and index that the body is stored at
- remove transaction hash to body lookup in the pending pool
"""
transaction_key = TransactionKey(block_header.block_number, index)
self.db.set(
make_transaction_hash_to_block_lookup_key(transaction_hash),
rlp.encode(transaction_key),
)
# because transaction is now in canonical chain, can now remove from pending txn lookups
lookup_key = make_transaction_hash_to_data_lookup_key(transaction_hash)
if self.db.exists(lookup_key):
self.db.delete(lookup_key)
def add_pending_transaction(self, transaction):
self.db.set(
make_transaction_hash_to_data_lookup_key(transaction.hash),
rlp.encode(transaction),
)
def add_transaction(self, block_header, index_key, transaction):
transaction_db = HexaryTrie(self.db,
root_hash=block_header.transaction_root)
transaction_db[index_key] = rlp.encode(transaction)
return transaction_db.root_hash
def add_receipt(self, block_header, index_key, receipt):
receipt_db = HexaryTrie(db=self.db,
root_hash=block_header.receipt_root)
receipt_db[index_key] = rlp.encode(receipt)
return receipt_db.root_hash
def snapshot(self):
return self.db.snapshot()
def revert(self, checkpoint):
self.db.revert(checkpoint)
def commit(self, checkpoint):
self.db.commit(checkpoint)
def clear(self):
self.db.clear()
def get_state_db(self, state_root, read_only):
return AccountStateDB(db=self.db,
root_hash=state_root,
read_only=read_only)
class BaseChainDB:
def __init__(self, db):
self.db = JournalDB(db)
def exists(self, key):
return self.db.exists(key)
def get_canonical_head(self):
if not self.exists(CANONICAL_HEAD_HASH_DB_KEY):
raise CanonicalHeadNotFound("No canonical head set for this chain")
return self.get_block_header_by_hash(
self.db.get(CANONICAL_HEAD_HASH_DB_KEY))
def get_canonical_block_header_by_number(self, block_number):
"""
Returns the block header with the given number in the canonical chain.
Raises BlockNotFound if there's no block header with the given number in the
canonical chain.
"""
validate_uint256(block_number, title="Block Number")
return self.get_block_header_by_hash(
self.lookup_block_hash(block_number))
def get_score(self, block_hash):
return rlp.decode(self.db.get(
make_block_hash_to_score_lookup_key(block_hash)),
sedes=rlp.sedes.big_endian_int)
def set_as_canonical_chain_head(self, header):
"""
Sets the header as the canonical chain HEAD.
"""
for h in reversed(self.find_common_ancestor(header)):
self.add_block_number_to_hash_lookup(h)
try:
self.get_block_header_by_hash(header.hash)
except BlockNotFound:
raise ValueError(
"Cannot use unknown block hash as canonical head: {}".format(
header.hash))
self.db.set(CANONICAL_HEAD_HASH_DB_KEY, header.hash)
@to_tuple
def find_common_ancestor(self, header):
"""
Returns the chain leading up from the given header until the first ancestor it has in
common with our canonical chain.
"""
h = header
while True:
yield h
if h.parent_hash == GENESIS_PARENT_HASH:
break
try:
orig = self.get_canonical_block_header_by_number(
h.block_number)
except KeyError:
# This just means the block is not on the canonical chain.
pass
else:
if orig.hash == h.hash:
# Found the common ancestor, stop.
break
h = self.get_block_header_by_hash(h.parent_hash)
def get_block_header_by_hash(self, block_hash):
"""
Returns the requested block header as specified by block hash.
Raises BlockNotFound if it is not present in the db.
"""
validate_word(block_hash, title="Block Hash")
try:
block = self.db.get(block_hash)
except KeyError:
raise BlockNotFound("No block with hash {0} found".format(
encode_hex(block_hash)))
return rlp.decode(block, sedes=BlockHeader)
def header_exists(self, block_hash):
"""Returns True if the header with the given block hash is in our DB."""
return self.db.exists(block_hash)
def lookup_block_hash(self, block_number):
"""
Return the block hash for the given block number.
"""
validate_uint256(block_number, title="Block Number")
number_to_hash_key = make_block_number_to_hash_lookup_key(block_number)
# TODO: can raise KeyError
block_hash = rlp.decode(
self.db.get(number_to_hash_key),
sedes=rlp.sedes.binary,
)
return block_hash
def get_block_uncles(self, uncles_hash):
validate_word(uncles_hash, title="Uncles Hash")
return rlp.decode(self.db.get(uncles_hash),
sedes=rlp.sedes.CountableList(BlockHeader))
@to_list
def get_receipts(self, header, receipt_class):
receipt_db = Trie(db=self.db, root_hash=header.receipt_root)
for receipt_idx in itertools.count():
receipt_key = rlp.encode(receipt_idx)
if receipt_key in receipt_db:
receipt_data = receipt_db[receipt_key]
yield rlp.decode(receipt_data, sedes=receipt_class)
else:
break
@to_list
def get_block_transactions(self, block_header, transaction_class):
transaction_db = Trie(self.db, root_hash=block_header.transaction_root)
for transaction_idx in itertools.count():
transaction_key = rlp.encode(transaction_idx)
if transaction_key in transaction_db:
transaction_data = transaction_db[transaction_key]
yield rlp.decode(transaction_data, sedes=transaction_class)
else:
break
def add_block_number_to_hash_lookup(self, header):
block_number_to_hash_key = make_block_number_to_hash_lookup_key(
header.block_number)
self.db.set(
block_number_to_hash_key,
rlp.encode(header.hash, sedes=rlp.sedes.binary),
)
# TODO: This method sould take a chain of headers as that's the most common use case
# and it'd be much faster than inserting each header individually.
def persist_header_to_db(self, header):
if header.parent_hash != GENESIS_PARENT_HASH and not self.header_exists(
header.parent_hash):
raise ParentNotFound(
"Cannot persist block header ({}) with unknown parent ({})".
format(encode_hex(header.hash),
encode_hex(header.parent_hash)))
self.db.set(
header.hash,
rlp.encode(header),
)
if header.parent_hash == GENESIS_PARENT_HASH:
score = header.difficulty
else:
score = self.get_score(header.parent_hash) + header.difficulty
self.db.set(make_block_hash_to_score_lookup_key(header.hash),
rlp.encode(score, sedes=rlp.sedes.big_endian_int))
try:
head_score = self.get_score(self.get_canonical_head().hash)
except CanonicalHeadNotFound:
self.set_as_canonical_chain_head(header)
else:
if score > head_score:
self.set_as_canonical_chain_head(header)
def persist_block_to_db(self, block):
self.persist_header_to_db(block.header)
# Persist the transactions
transaction_db = Trie(self.db, root_hash=BLANK_ROOT_HASH)
for i in range(len(block.transactions)):
index_key = rlp.encode(i, sedes=rlp.sedes.big_endian_int)
transaction_db[index_key] = rlp.encode(block.transactions[i])
assert transaction_db.root_hash == block.header.transaction_root
# Persist the uncles list
self.db.set(
block.header.uncles_hash,
rlp.encode(block.uncles,
sedes=rlp.sedes.CountableList(type(block.header))),
)
def add_transaction(self, block_header, index_key, transaction):
transaction_db = Trie(self.db, root_hash=block_header.transaction_root)
transaction_db[index_key] = rlp.encode(transaction)
return transaction_db.root_hash
def add_receipt(self, block_header, index_key, receipt):
receipt_db = Trie(db=self.db, root_hash=block_header.receipt_root)
receipt_db[index_key] = rlp.encode(receipt)
return receipt_db.root_hash
def snapshot(self):
return self.db.snapshot()
def revert(self, checkpoint):
self.db.revert(checkpoint)
def commit(self, checkpoint):
self.db.commit(checkpoint)
def clear(self):
self.db.clear()
def get_state_db(self, state_root, read_only):
return State(db=self.db, root_hash=state_root, read_only=read_only)