def __getitem__(self, block_id):
"""Construct block query or get a block range.
block_id could be one of:
- int: Block level or offset from the head if negative;
- str: Block hash (base58) or special names (head, genesis), expressions like `head~1` etc;
- slice [:]: First value (start) must be int, second (stop) can be any Block ID or empty.
:param block_id: Block identity or block range
:rtype: BlockQuery or BlockSliceQuery
"""
if isinstance(block_id, slice):
if isinstance(block_id.start, str):
block_id = slice(
self._get_block(block_id.start).level(), block_id.stop,
None)
elif not isinstance(block_id.start, int):
raise NotImplementedError('Slice start should be an integer.')
return BlockSliceQuery(
start=block_id.start,
stop=block_id.stop,
node=self.node,
path=self._wild_path,
params=self._params,
)
if isinstance(block_id, int) and block_id < 0:
head_level = self._get_block('head').level()
block_id = max(0, head_level + block_id)
return self._get_block(block_id)
def __getitem__(self, block_id):
""" Construct block query or get a block range.
:param block_id: Block identity or block range
- int: Block level or offset from the head if negative;
- str: Block hash (base58) or special names (head, genesis), expressions like `head~1` etc;
- slice [:]: First value (start) must be int, second (stop) can be any Block ID or empty.
:rtype: BlockQuery or BlockSliceQuery
"""
if isinstance(block_id, slice):
if not isinstance(block_id.start, int):
raise NotImplementedError('Slice start should be an integer.')
return BlockSliceQuery(
start=block_id.start,
stop=block_id.stop,
node=self.node,
path=self._wild_path,
params=self._params
)
if isinstance(block_id, int) and block_id < 0:
return self.blocks[f'head~{block_id}']
return super(BlocksQuery, self).__getitem__(block_id)
def current_cycle(self):
"""
Get block range for the current cycle.
:return: BlockSliceQuery
"""
metadata = self.head.metadata()
return BlockSliceQuery(start=metadata['level']['level'] -
metadata['level']['cycle_position'],
stop='head',
node=self.node,
path=self._wild_path,
params=self._params)
def current_voting_period(self):
""" Get block range for the current voting period.
:rtype: BlockSliceQuery
"""
metadata = self.head.metadata()
return BlockSliceQuery(start=metadata['level']['level'] -
metadata['level']['voting_period_position'],
stop='head',
node=self.node,
path=self._wild_path,
params=self._params)