def _build_candidate_block(self, chain_head):
""" Build a candidate block and construct the consensus object to
validate it.
:param chain_head: The block to build on top of.
:return: (BlockBuilder) - The candidate block in a BlockBuilder
wrapper.
"""
state_view = BlockWrapper.state_view_for_block(
chain_head, self._state_view_factory)
consensus_module = ConsensusFactory.get_configured_consensus_module(
chain_head.header_signature, state_view)
# using chain_head so so we can use the setting_cache
max_batches = int(
self._settings_cache.get_setting(
'sawtooth.publisher.max_batches_per_block',
chain_head.state_root_hash,
default_value=0))
public_key = self._identity_signer.get_public_key().as_hex()
consensus = consensus_module.\
BlockPublisher(block_cache=self._block_cache,
state_view_factory=self._state_view_factory,
batch_publisher=self._batch_publisher,
data_dir=self._data_dir,
config_dir=self._config_dir,
validator_id=public_key)
batch_injectors = []
if self._batch_injector_factory is not None:
batch_injectors = self._batch_injector_factory.create_injectors(
chain_head.identifier)
if batch_injectors:
LOGGER.debug("Loaded batch injectors: %s", batch_injectors)
block_header = BlockHeader(
block_num=chain_head.block_num + 1,
previous_block_id=chain_head.header_signature,
signer_public_key=public_key)
block_builder = BlockBuilder(block_header)
if not consensus.initialize_block(block_builder.block_header):
if not self._logging_states.consensus_not_ready:
self._logging_states.consensus_not_ready = True
LOGGER.debug("Consensus not ready to build candidate block.")
return None
if self._logging_states.consensus_not_ready:
self._logging_states.consensus_not_ready = False
LOGGER.debug("Consensus is ready to build candidate block.")
# create a new scheduler
scheduler = self._transaction_executor.create_scheduler(
self._squash_handler, chain_head.state_root_hash)
# build the TransactionCommitCache
committed_txn_cache = TransactionCommitCache(
self._block_cache.block_store)
self._transaction_executor.execute(scheduler)
self._candidate_block = _CandidateBlock(self._block_cache.block_store,
consensus, scheduler,
committed_txn_cache,
block_builder, max_batches,
batch_injectors)
for batch in self._pending_batches:
if self._candidate_block.can_add_batch:
self._candidate_block.add_batch(batch)
else:
break
def generate_block(self,
previous_block=None,
add_to_store=False,
add_to_cache=False,
batch_count=1,
batches=None,
status=BlockStatus.Unknown,
invalid_consensus=False,
invalid_batch=False,
invalid_signature=False,
weight=0):
previous = self._get_block(previous_block)
if previous is None:
previous = self.chain_head
header = BlockHeader(
previous_block_id=previous.identifier,
signer_public_key=self.identity_signer.get_public_key().as_hex(),
block_num=previous.block_num + 1)
block_builder = BlockBuilder(header)
if batches:
block_builder.add_batches(batches)
if batch_count != 0:
block_builder.add_batches(
[self._generate_batch() for _ in range(batch_count)])
if invalid_batch:
block_builder.add_batches(
[self._generate_batch_from_payload('BAD')])
block_builder.set_state_hash('0' * 70)
consensus = mock_consensus.BlockPublisher()
consensus.finalize_block(block_builder.block_header, weight=weight)
header_bytes = block_builder.block_header.SerializeToString()
signature = self.identity_signer.sign(header_bytes)
block_builder.set_signature(signature)
block_wrapper = BlockWrapper(block_builder.build_block())
if batches:
block_wrapper.block.batches.extend(batches)
if batch_count:
block_wrapper.block.batches.extend(
[self.generate_batch() for _ in range(batch_count)])
if invalid_signature:
block_wrapper.block.header_signature = "BAD"
if invalid_consensus:
block_wrapper.header.consensus = b'BAD'
block_wrapper.status = status
if add_to_cache:
self.block_cache[block_wrapper.identifier] = block_wrapper
if add_to_store:
self.block_store[block_wrapper.identifier] = block_wrapper
LOGGER.debug("Generated %s", dumps_block(block_wrapper))
return block_wrapper
def create_block_header(self, signer_public_key=None):
return BlockHeader(signer_public_key=signer_public_key)
def _list_store_resources(self, request, head_id, filter_ids,
resource_fetcher, block_xform):
"""Builds a list of blocks or resources derived from blocks,
handling multiple possible filter requests:
- filtered by a set of ids
- filtered by head block
- filtered by both id and head block
- not filtered (all current resources)
Note:
This method will fail if `_block_store` has not been set
Args:
request (object): The parsed protobuf request object
head_id (str): Either request.head_id, or the current chain head
filter_ids (list of str): the resource ids (if any) to filter by
resource_fetcher (function): Fetches a resource by its id
Expected args:
resource_id: The id of the resource to be fetched
Expected return:
object: The resource to be appended to the results
block_xform (function): Transforms a block into a list of resources
Expected args:
block: A block object from the block store
Expected return:
list: To be concatenated to the end of the results
Returns:
list: List of blocks or data from blocks. If filtered by ids,
they will be listed in the same order as the id filters,
otherwise they will be ordered from newest to oldest
"""
resources = []
# Simply fetch by id if filtered by id but not by head block
if filter_ids and not request.head_id:
for resource_id in filter_ids:
try:
resources.append(resource_fetcher(resource_id))
except (KeyError, ValueError, TypeError):
# Invalid ids should be omitted, not raise an exception
pass
# Traverse block chain to build results for most scenarios
else:
current_id = head_id
while current_id in self._block_store:
block = self._block_store[current_id].block
resources += block_xform(block)
header = BlockHeader()
header.ParseFromString(block.header)
current_id = header.previous_block_id
# If filtering by head AND ids, the traverse results must be winnowed
if request.head_id and filter_ids:
matches = {
r.header_signature: r
for r in resources if r.header_signature in filter_ids
}
resources = [matches[i] for i in filter_ids if i in matches]
return resources
class BlockWrapper(object):
"""
Utility class to make accessing block members more convenient.
This also add storage of the weight and status used by the Journal
components to track the state of a block. This is the object type
stored in the Block Cache.
"""
def __init__(self, block, weight=0, status=BlockStatus.Unknown):
self.block = block
self._block_header = None
self.weight = weight # the block weight calculated by the
# consensus algorithm.
self.status = status # One of the BlockStatus types.
self.execution_results = []
self.num_transactions = 0
@staticmethod
def wrap(block, weight=0, status=BlockStatus.Unknown):
if isinstance(block, BlockWrapper):
return block
return BlockWrapper(block, weight=weight, status=status)
@property
def batches(self):
"""
Returns the consensus object of the block.
"""
return self.block.batches
@property
def consensus(self):
"""
Returns the consensus object of the block.
"""
return self.header.consensus
def get_block(self):
"""
Return the wrapped block object.
"""
return self.block
@property
def header(self):
"""
Returns the header of the block
"""
if self._block_header is None:
self._block_header = BlockHeader()
self._block_header.ParseFromString(self.block.header)
return self._block_header
@property
def header_signature(self):
"""
Returns the header signature of the block
"""
return self.block.header_signature
@property
def identifier(self):
"""
Returns the identifier of the block, currently the
header signature
"""
return self.block.header_signature
@property
def block_num(self):
"""
Returns the depth or block_number
"""
return self.header.block_num
@property
def state_root_hash(self):
"""
Returns the state root hash
"""
return self.header.state_root_hash
@property
def previous_block_id(self):
"""
Returns the identifier of the previous block.
"""
return self.header.previous_block_id
@staticmethod
def state_view_for_block(block_wrapper, state_view_factory):
"""
Returns the state view for an arbitrary block.
Args:
block_wrapper (BlockWrapper): The block for which a state
view is to be returned
state_view_factory (StateViewFactory): The state view factory
used to create the StateView object
Returns:
StateView object associated with the block
"""
state_root_hash = \
block_wrapper.state_root_hash \
if block_wrapper is not None else None
return state_view_factory.create_view(state_root_hash)
def get_state_view(self, state_view_factory):
"""
Returns the state view associated with this block
Args:
state_view_factory (StateViewFactory): The state view factory
used to create the StateView object
Returns:
StateView object
"""
return BlockWrapper.state_view_for_block(self, state_view_factory)
def __repr__(self):
return "{}({}, S:{}, P:{})". \
format(self.identifier, self.block_num,
self.state_root_hash, self.previous_block_id)
def __str__(self):
return "{} (block_num:{}, state:{}, previous_block_id:{})".format(
self.identifier,
self.block_num,
self.state_root_hash,
self.previous_block_id,
)
