olympic_winners.py

import sys
from ethereum import trie
from ethereum.securetrie import SecureTrie
from ethereum import blocks
import ethereum.chain
from pyethapp.leveldb_service import LevelDB
from ethereum.utils import big_endian_to_int

db = LevelDB(sys.argv[1])

# monkeypatch to old non pruning trie implementation
ethereum.chain.trie = trie
blocks.trie = trie
blocks.Trie = trie.Trie


def nonce_storage(blk, address):
    account = blk._get_acct(address)
    storage_keys = 0
    storage_trie = SecureTrie(trie.Trie(blk.db, account.storage))
    for k, v in storage_trie.iter_branch():
        if v is not None:
            storage_keys += 1
    return account.nonce, storage_keys

chain = ethereum.chain.Chain(db)
head = chain.head
print "chain head", head



class MDict(dict):
    _len = 5

    def add(self, value, address):
        if len(self) < self._len:
            self[value] = address
            return True
        s = min(self.keys())
        if value > s:
            del self[s]
            self[value] = address
            return True
        assert s >= value

    def __repr__(self):
        return repr(sorted(self.items(), reverse=True))


highest_nonce = MDict()
most_storage_keys = MDict()
lowest_address = MDict()

for num_accounts, (address, v) in enumerate(head.state.iter_branch()):
    if num_accounts % 1000 == 0:
        print "processed accounts", num_accounts, len(db.uncommitted)
    if len(db.uncommitted) > 50 * 1000 * 1000:
            db.uncommitted = {}  # delete cache

    a = blocks.encode_hex(address)
    nonce, num_keys = nonce_storage(head, address)
    if highest_nonce.add(nonce, a):
        print 'best nonces', highest_nonce
    if most_storage_keys.add(num_keys, a):
        print 'most storage keys', most_storage_keys
        db.uncommitted = {}
    address = big_endian_to_int(address)
    if nonce > 0 and address > 4 and lowest_address.add(2**256 - address, a):
        print 'lowest addresses', lowest_address


print "DONE", "-" * 30
print "chain head", head
print "iterated over %d accounts" % num_accounts
print 'best nonce', highest_nonce
print 'most storage keys', most_storage_keys
print 'lowest address', lowest_address