def sign(self):
""" Sign a provided transaction witht he provided key(s)
:param dict tx: The transaction to be signed and returned
:param string wifs: One or many wif keys to use for signing
a transaction. If not present, the keys will be loaded
from the wallet as defined in "missing_signatures" key
of the transactions.
"""
# We need to set the default prefix, otherwise pubkeys are
# presented wrongly!
if self.steemd:
operations.default_prefix = self.steemd.chain_params["prefix"]
elif "blockchain" in self:
operations.default_prefix = self["blockchain"]["prefix"]
try:
signedtx = SignedTransaction(**self.json())
except Exception as e:
raise e
if not any(self.wifs):
raise MissingKeyError
signedtx.sign(self.wifs, chain=self.steemd.chain_params)
self["signatures"].extend(signedtx.json().get("signatures"))