def get_chain(data_dir=default_data_dir):
"""
returns an ethereum.chain.Chain instance
"""
dbfile = os.path.join(data_dir, 'leveldb')
db = LevelDB(dbfile)
return Chain(Env(db))
DB_DIR = '/tmp/%d' % random.randrange(int(time.time() * 1000000))
if '--db' in sys.argv:
DB_DIR = int(sys.argv[sys.argv.index('--db') + 1])
_path, _file = os.path.split(STATE_LOAD_FN)
if _file in os.listdir(os.path.join(os.getcwd(), _path)):
print('loading state from %s ...' % STATE_LOAD_FN)
c = chain.Chain(json.load(open(STATE_LOAD_FN)), Env())
print('loaded.')
elif 'genesis_frontier.json' not in os.listdir(os.getcwd()):
print('Please download genesis_frontier.json from ' +
'http://vitalik.ca/files/genesis_frontier.json')
sys.exit()
else:
c = chain.Chain(json.load(open('genesis_frontier.json')),
Env(LevelDB(DB_DIR)))
assert c.state.trie.root_hash.encode('hex') == \
'd7f8974fb5ac78d9ac099b9ad5018bedc2ce0a72dad1827a1709da30580f0544'
assert c.state.prev_headers[0].hash.encode('hex') == \
'd4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec8c0db1cb8fa3'
print('state generated from genesis')
print('Attempting to open %s' % RLP_BLOCKS_FILE)
_path, _file = os.path.split(RLP_BLOCKS_FILE)
if not _path or _file not in os.listdir(_path):
print(
'Please download 200kblocks.rlp from http://vitalik.ca/files/200kblocks.rlp '
+ 'and put it in this directory to continue the test')
sys.exit()
f = open(RLP_BLOCKS_FILE)