def validate(self, bigchain, current_transactions=[]):
"""Validate election transaction
For more details refer BEP-21: https://github.com/bigchaindb/BEPs/tree/master/21
NOTE:
* A valid election is initiated by an existing validator.
* A valid election is one where voters are validators and votes are
alloacted according to the voting power of each validator node.
Args:
bigchain (BigchainDB): an instantiated bigchaindb.lib.BigchainDB object.
Returns:
ValidatorElection object
Raises:
ValidationError: If the election is invalid
"""
input_conditions = []
duplicates = any(txn for txn in current_transactions
if txn.id == self.id)
if bigchain.get_transaction(self.id) or duplicates:
raise DuplicateTransaction(
'transaction `{}` already exists'.format(self.id))
if not self.inputs_valid(input_conditions):
raise InvalidSignature('Transaction signature is invalid.')
current_validators = self.get_validators(bigchain)
# NOTE: Proposer should be a single node
if len(self.inputs) != 1 or len(self.inputs[0].owners_before) != 1:
raise MultipleInputsError(
'`tx_signers` must be a list instance of length one')
# NOTE: change more than 1/3 of the current power is not allowed
if self.asset['data']['power'] >= (1 / 3) * sum(
current_validators.values()):
raise InvalidPowerChange(
'`power` change must be less than 1/3 of total power')
# NOTE: Check if the proposer is a validator.
[election_initiator_node_pub_key] = self.inputs[0].owners_before
if election_initiator_node_pub_key not in current_validators.keys():
raise InvalidProposer(
'Public key is not a part of the validator set')
# NOTE: Check if all validators have been assigned votes equal to their voting power
if not self.is_same_topology(current_validators, self.outputs):
raise UnequalValidatorSet(
'Validator set much be exactly same to the outputs of election'
)
return self
def validate(self, bigchain, current_transactions=[]):
"""For more details refer BEP-21: https://github.com/bigchaindb/BEPs/tree/master/21
"""
current_validators = self.get_validators(bigchain)
super(ValidatorElection, self).validate(bigchain, current_transactions=current_transactions)
# NOTE: change more than 1/3 of the current power is not allowed
if self.asset['data']['power'] >= (1/3)*sum(current_validators.values()):
raise InvalidPowerChange('`power` change must be less than 1/3 of total power')
return self