def bucket_candidates(self, buckets, sufficient_funds):
'''Returns a list of bucket sets.'''
candidates = set()
# Add all singletons
for n, bucket in enumerate(buckets):
if sufficient_funds([bucket]):
candidates.add((n, ))
# And now some random ones
attempts = min(100, (len(buckets) - 1) * 10 + 1)
permutation = range(len(buckets))
for i in range(attempts):
# Get a random permutation of the buckets, and
# incrementally combine buckets until sufficient
self.p.shuffle(permutation)
bkts = []
for count, index in enumerate(permutation):
bkts.append(buckets[index])
if sufficient_funds(bkts):
candidates.add(tuple(sorted(permutation[:count + 1])))
break
else:
raise NotEnoughFunds()
candidates = [[buckets[n] for n in c] for c in candidates]
return [strip_unneeded(c, sufficient_funds) for c in candidates]
def choose_buckets(self, buckets, spent_amount, fee):
'''Spend the oldest buckets first.'''
# Unconfirmed coins are young, not old
adj_height = lambda height: 99999999 if height == 0 else height
buckets.sort(
key=lambda b: max(adj_height(coin['height']) for coin in b.coins))
selected, value, size = [], 0, 0
for bucket in buckets:
selected.append(bucket)
value += bucket.value
size += bucket.size
if value >= spent_amount + fee(size):
break
else:
raise NotEnoughFunds()
# Remove unneeded inputs starting with the smallest.
selected.sort(key=lambda b: b.value)
dropped = []
for bucket in selected:
if value - bucket.value >= spent_amount + fee(size - bucket.size):
value -= bucket.value
size -= bucket.size
dropped.append(bucket)
return [bucket for bucket in selected if bucket not in dropped]
def choose_buckets(self, buckets, sufficient_funds, penalty_func):
'''Spend the oldest buckets first.'''
# Unconfirmed coins are young, not old
adj_height = lambda height: 99999999 if height == 0 else height
buckets.sort(
key=lambda b: max(adj_height(coin['height']) for coin in b.coins))
selected = []
for bucket in buckets:
selected.append(bucket)
if sufficient_funds(selected):
return strip_unneeded(selected, sufficient_funds)
else:
raise NotEnoughFunds()