def export_transactions(chain, head_number=None):
"""
Export transactions
rlp and hex encoded, separated by newline
"""
head_number = head_number or chain.head.header.number
block_number = 0
seen = 0
while block_number < head_number:
h = chain.index.get_block_by_number(block_number)
raw = chain.blockchain.get(h)
# block [[], [], []]
typ, length, end = consume_length_prefix(raw, 0)
assert typ == list
typ, length, end = consume_length_prefix(raw, end) # header list
assert typ == list
txs_start = end + length
typ, length, end = consume_length_prefix(raw, txs_start) # tx list
txrlp = raw[txs_start:end + length]
r = rlp.decode(txrlp)
assert isinstance(r, list)
for tx in r:
s = rlp.encode(tx)
rlp.decode(s, Transaction)
print s.encode('hex')
seen += 1
_progress(seen)
block_number += 1
def compare_length(rlpdata, length):
_, _typ, _len, _pos = consume_length_prefix(rlpdata, 0)
assert _typ is list
lenlist = 0
if rlpdata == EMPTYLIST:
return -1 if length > 0 else 1 if length < 0 else 0
while 1:
if lenlist > length:
return 1
_, _, _l, _p = consume_length_prefix(rlpdata, _pos)
lenlist += 1
if _l + _p >= len(rlpdata):
break
_pos = _l + _p
return 0 if lenlist == length else -1
def get_packet_decoder(encoded_packet: bytes) -> Callable[[bytes], Packet]:
# Both message and WhoAreYou packets start with 32 bytes (either magic or tag) followed by rlp
# encoded data. Only in the case of message packets this is followed by the encrypted message.
# Therefore, we distinguish the two by reading the RLP length prefix and then checking if there
# is additional data.
if MAGIC_SIZE != TAG_SIZE:
raise Exception(
"Invariant: This check works as magic and tag size are equal"
)
prefix_size = MAGIC_SIZE
if len(encoded_packet) < prefix_size + 1:
raise ValidationError(f"Packet is with {len(encoded_packet)} bytes too short")
try:
_, _, rlp_size, _ = consume_length_prefix(encoded_packet, MAGIC_SIZE)
except DecodingError as error:
raise ValidationError("RLP section of packet starts with invalid length prefix") from error
expected_who_are_you_size = prefix_size + 1 + rlp_size
if len(encoded_packet) > expected_who_are_you_size:
return decode_message_packet
elif len(encoded_packet) == expected_who_are_you_size:
return decode_who_are_you_packet
else:
raise ValidationError("RLP section of packet is incomplete")
def decode(self, data):
# cmdid = rlp.peek(data, 0, sedes=t_int) # cmdid is first element
t, l, pos = consume_length_prefix(data, 0)
cmdid = t_int.deserialize(consume_item(data[pos], 0)[0])
cls = self.message_class_by_id[cmdid]
print 'DECODING', cls
return cls.decode(data)
