def _get_canonical_block_header_by_number(
cls,
db: BaseDB,
block_number: BlockNumber) -> BlockHeader:
validate_block_number(block_number)
canonical_block_hash = cls._get_canonical_block_hash(db, block_number)
return cls._get_block_header_by_hash(db, canonical_block_hash)
def get_vm_class_for_block_number(cls, block_number: BlockNumber) -> Type[VirtualMachineAPI]:
if cls.vm_configuration is None:
raise AttributeError("Chain classes must define the VMs in vm_configuration")
validate_block_number(block_number)
for start_block, vm_class in reversed(cls.vm_configuration):
if block_number >= start_block:
return vm_class
else:
raise VMNotFound(f"No vm available for block #{block_number}")
def get_canonical_block_header_by_number(
self, block_number: BlockNumber) -> BlockHeader:
"""
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_block_number(block_number, title="Block Number")
return self.get_block_header_by_hash(
self.get_canonical_block_hash(block_number))
def _get_canonical_block_hash(db: BaseDB, block_number: BlockNumber) -> Hash32:
validate_block_number(block_number)
number_to_hash_key = SchemaV1.make_block_number_to_hash_lookup_key(block_number)
try:
encoded_key = db[number_to_hash_key]
except KeyError:
raise HeaderNotFound(
"No canonical header for block number #{0}".format(block_number)
)
else:
return rlp.decode(encoded_key, sedes=rlp.sedes.binary)
def get_vm_class_for_block_number(cls, block_number: BlockNumber) -> Type['BaseVM']:
"""
Returns the VM class for the given block number.
"""
if cls.vm_configuration is None:
raise AttributeError("Chain classes must define the VMs in vm_configuration")
validate_block_number(block_number)
for start_block, vm_class in reversed(cls.vm_configuration):
if block_number >= start_block:
return vm_class
else:
raise VMNotFound("No vm available for block #{0}".format(block_number))
def get_canonical_block_hash(self, block_number: BlockNumber) -> Hash32:
"""
Returns the block hash for the canonical block at the given number.
Raises BlockNotFound if there's no block header with the given number in the
canonical chain.
"""
validate_block_number(block_number, title="Block Number")
number_to_hash_key = SchemaV1.make_block_number_to_hash_lookup_key(
block_number)
try:
encoded_key = self.db[number_to_hash_key]
except KeyError:
raise HeaderNotFound(
"No canonical header for block number #{0}".format(
block_number))
else:
return rlp.decode(encoded_key, sedes=rlp.sedes.binary)
def test_validate_block_number(block_number, is_valid):
if is_valid:
validate_block_number(block_number)
else:
with pytest.raises(ValidationError):
validate_block_number(block_number)
