28 lines
778 B
Python
28 lines
778 B
Python
from binascii import hexlify
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class FindShortestID:
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__slots__ = 'short_id', 'new_id'
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def __init__(self):
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self.short_id = b''
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self.new_id = None
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def step(self, other_hash, new_hash):
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if self.new_id is None:
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self.new_id = hexlify(new_hash[::-1])
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other_id = hexlify(other_hash[::-1])
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for i in range(len(self.new_id)):
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if other_id[i] != self.new_id[i]:
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if i > len(self.short_id)-1:
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self.short_id = self.new_id[:i+1]
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break
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def finalize(self):
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if self.short_id:
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return '#'+self.short_id.decode()
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return ''
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def register_canonical_functions(connection):
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connection.create_aggregate("shortest_id", 2, FindShortestID)
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