def get_next_difficulty(self, header_hash: bytes32, new_slot: bool) -> uint64:
assert self.contains_sub_block(header_hash)
curr = self.sub_block_record(header_hash)
if curr.height <= 2:
return self.constants.DIFFICULTY_STARTING
return get_next_difficulty(
self.constants,
self,
header_hash,
curr.height,
uint64(curr.weight - self.sub_block_record(curr.prev_hash).weight),
curr.deficit,
new_slot,
curr.sp_total_iters(self.constants),
)
def get_next_difficulty(self, header_hash: bytes32,
new_slot: bool) -> uint64:
assert header_hash in self.sub_blocks
curr = self.sub_blocks[header_hash]
if curr.sub_block_height <= 2:
return self.constants.DIFFICULTY_STARTING
return get_next_difficulty(
self.constants,
self.sub_blocks,
self.sub_height_to_hash,
header_hash,
curr.sub_block_height,
uint64(curr.weight - self.sub_blocks[curr.prev_hash].weight),
curr.deficit,
new_slot,
curr.sp_total_iters(self.constants),
)
def next_sub_epoch_summary(
constants: ConsensusConstants,
blocks: BlockchainInterface,
required_iters: uint64,
block: Union[UnfinishedBlock, FullBlock],
can_finish_soon: bool = False,
) -> Optional[SubEpochSummary]:
"""
Returns the sub-epoch summary that can be included in the block after block. If it should include one. Block
must be eligible to be the last block in the epoch. If not, returns None. Assumes that there is a new slot
ending after block.
Args:
constants: consensus constants being used for this chain
blocks: interface to cached SBR
required_iters: required iters of the proof of space in block
block: the (potentially) last block in the new epoch
can_finish_soon: this is useful when sending SES to timelords. We might not be able to finish it, but we will
soon (within MAX_SUB_SLOT_BLOCKS)
Returns:
object: the new sub-epoch summary
"""
signage_point_index = block.reward_chain_block.signage_point_index
prev_b: Optional[BlockRecord] = blocks.try_block_record(
block.prev_header_hash)
if prev_b is None or prev_b.height == 0:
return None
if len(block.finished_sub_slots) > 0 and block.finished_sub_slots[
0].challenge_chain.new_difficulty is not None:
# We just included a sub-epoch summary
return None
assert prev_b is not None
# This is the ssi of the current block
sub_slot_iters = get_next_sub_slot_iters(
constants,
blocks,
prev_b.prev_hash,
prev_b.height,
prev_b.sub_slot_iters,
prev_b.deficit,
len(block.finished_sub_slots) > 0,
prev_b.sp_total_iters(constants),
)
overflow = is_overflow_block(constants, signage_point_index)
deficit = calculate_deficit(
constants,
uint32(prev_b.height + 1),
prev_b,
overflow,
len(block.finished_sub_slots),
)
can_finish_se, can_finish_epoch = can_finish_sub_and_full_epoch(
constants,
uint32(prev_b.height + 1),
deficit,
blocks,
prev_b.header_hash if prev_b is not None else None,
can_finish_soon,
)
# can't finish se, no summary
if not can_finish_se:
return None
next_difficulty = None
next_sub_slot_iters = None
# if can finish epoch, new difficulty and ssi
if can_finish_epoch:
sp_iters = calculate_sp_iters(constants, sub_slot_iters,
signage_point_index)
ip_iters = calculate_ip_iters(constants, sub_slot_iters,
signage_point_index, required_iters)
next_difficulty = get_next_difficulty(
constants,
blocks,
block.prev_header_hash,
uint32(prev_b.height + 1),
uint64(prev_b.weight -
blocks.block_record(prev_b.prev_hash).weight),
deficit,
True,
uint128(block.total_iters - ip_iters + sp_iters -
(sub_slot_iters if overflow else 0)),
True,
)
next_sub_slot_iters = get_next_sub_slot_iters(
constants,
blocks,
block.prev_header_hash,
uint32(prev_b.height + 1),
sub_slot_iters,
deficit,
True,
uint128(block.total_iters - ip_iters + sp_iters -
(sub_slot_iters if overflow else 0)),
True,
)
return make_sub_epoch_summary(
constants,
blocks,
uint32(prev_b.height + 2),
prev_b,
next_difficulty,
next_sub_slot_iters,
)