def addTrxn(self, workTangle, workNode):
tips = workTangle.find_tips()
tipObjs = []
for tip in tips:
tipObjs.append(workTangle.bundleObjects.get(tip))
genBundle = Bundle(tips, tipObjs, workNode) # Generate basic bundle
metaTrxn = Trxn(genBundle)
genBundle.addTrxn(metaTrxn) # Add non-value trxn
workTangle.add_tx(
genBundle) # Record bundle with transaction in tangle and do PoW
class Tangle:
def __init__(self):
# One trxn with a bundle to start as genesis, random selection with replacement allows for growing tangle
# ==> URTS
# TGraph key {key: [trnxObject]}
self.genBundle = Bundle(None,None, None) # Setup genesis Bundle
self.genBundle.addTrxn(self.genBundle)
self.tGraph = {'genesis_trxn': [None]}
self.bundleObjects = {'genesis_trxn': self.genBundle}
# No data to start
self.tData = {}
# Five nodes for example
self.tLedger = {}
self.netNodes = []
self.tValues = {}
# Initialize the ledger with a balance for each virtual node.
def initLedger(self,node):
self.tLedger[node.address] = node.bal
self.netNodes.append(node)
# Add a bundle with a trxn to the tangle and verify with PoW
def add_tx(self,bundle: Bundle):
if bundle.branch in self.tGraph and bundle.trunk in self.tGraph:
if bundle.trxns[0].value != 0:
if self.check_value_tx(bundle):
self.move_money(bundle)
logHash = bundle.get_hash()
self.tGraph[logHash] = [bundle.branch, bundle.trunk]
self.tData[logHash] = {'data_payload': bundle.data_payload,
'value_payloafdd': bundle.outputTrxn.value}
self.tValues[logHash] = bundle.data_payload
else:
logHash = bundle.get_hash()
self.tGraph[logHash] = [bundle.branch, bundle.trunk]
self.tData[logHash] = bundle.data_payload
self.bundleObjects[logHash] = bundle
# Get tips from tangle randomly (normally MCMC in old IOTA, modified URTS in new IOTA)
def find_tips(self):
# Uses URTS algorithm for selecting tips with replacement. Results in lazy tips.
tipChoices = list(set(self.tGraph.keys()))
return tuple(random.choices(tipChoices, k=2))
# Check if sender has the appropriate amount of crypto to send.
def check_value_tx(self,bundle):
if bundle.inputTrxn.senderAddr in self.tLedger:
# Check if sender has the crypto...
if abs(bundle.inputTrxn.value) <= self.tLedger[bundle.inputTrxn.senderAddr]:
res = True
return res
# Moves crypto from a sender to a receiver account
def move_money(self,bundle):
sendNode = None
recNode = None
for node in self.netNodes:
if node.address == bundle.inputTrxn.senderAddr:
sendNode = node
for node in self.netNodes:
if node.address == bundle.outputTrxn.recAddr:
recNode = node
self.tLedger[bundle.inputTrxn.senderAddr] += bundle.inputTrxn.value
sendNode.bal += bundle.inputTrxn.value
self.tLedger[bundle.outputTrxn.recAddr] += bundle.outputTrxn.value
recNode.bal += bundle.outputTrxn.value
