simulator.py

import random
import copy
import json
import random
import hashlib
from visualizer import report

from blocks import Block
from validator import Validator
from validator import ConsensusMessage
from validator import UnresolvedDeps
from generate_transactions import gen_alice_and_bob_tx

from config import *

# Setup
GENESIS_BLOCKS = {}
GENESIS_MESSAGES = []
for ID in SHARD_IDS:
    GENESIS_BLOCKS[ID] = Block(ID, sources={}) # temporarily set sources to {}, since genesis blocks are not known yet
    GENESIS_MESSAGES.append(ConsensusMessage(GENESIS_BLOCKS[ID], 0, []))  # The watcher is the sender of the genesis blocks

for ID in SHARD_IDS:
    GENESIS_BLOCKS[ID].sources = {ID : GENESIS_BLOCKS[ID] for ID in SHARD_IDS}
    GENESIS_BLOCKS[ID].parent_ID = None
    for _ in SHARD_IDS:
        if ID in INITIAL_TOPOLOGY[_]:
            GENESIS_BLOCKS[ID].parent_ID = _
    GENESIS_BLOCKS[ID].child_IDs = INITIAL_TOPOLOGY[ID]

validators = {}
for name in VALIDATOR_NAMES:
    validators[name] = Validator(name)

#  Watcher lives at validator name 0 and receives all the messages
watcher = validators[0]

for v in VALIDATOR_NAMES:
    for genesis_message in GENESIS_MESSAGES:
        validators[v].receive_consensus_message(genesis_message)

# GLOBAL MEMPOOLS
mempools = {}
txs = gen_alice_and_bob_tx()
for ID in SHARD_IDS:
    mempools[ID] = txs

# GLOBAL VIEWABLES
viewables = {}
for v in VALIDATOR_NAMES:
    viewables[v] = {}
    for w in VALIDATOR_NAMES:
        viewables[v][w] = []

max_height = 0

# SIMULATION LOOP:
for i in range(NUM_ROUNDS):
    # Make a new message from a random validator on a random shard
    rand_ID = random.choice(SHARD_IDS)
    next_proposer = rand.choice(SHARD_VALIDATOR_ASSIGNMENT[rand_ID])

    while next_proposer == 0:
        rand_ID = random.choice(SHARD_IDS)
        next_proposer = rand.choice(SHARD_VALIDATOR_ASSIGNMENT[rand_ID])

    # MAKE CONSENSUS MESSAGE
    new_message = validators[next_proposer].make_new_consensus_message(rand_ID, mempools, drain_amount=MEMPOOL_DRAIN_RATE, genesis_blocks=GENESIS_BLOCKS)
    watcher.receive_consensus_message(new_message)  # here the watcher is, receiving all the messages

    # keep max_height
    if new_message.height > max_height:
        max_height = new_message.height

    if FREE_INSTANT_BROADCAST:
        for v in VALIDATOR_NAMES:
            if v != 0:
                validators[v].receive_consensus_message(new_message)
    else:
        # MAKE NEW MESSAGE VIEWABLE
        for v in VALIDATOR_NAMES:
            if v == next_proposer or v == 0:
                continue
            viewables[v][next_proposer].append(new_message)  # validators have the possibility of later viewing this message

        # RECEIVE CONSENSUS MESSAGES WITHIN SHARD
        for j in range(NUM_WITHIN_SHARD_RECEIPTS_PER_ROUND):

            next_receiver = random.choice(SHARD_VALIDATOR_ASSIGNMENT[rand_ID])

            pool = copy.copy(SHARD_VALIDATOR_ASSIGNMENT[rand_ID])
            pool.remove(next_receiver)

            new_received = False
            while(not new_received and len(pool) > 0):

                receiving_from = random.choice(pool)
                pool.remove(receiving_from)

                if len(viewables[next_receiver][receiving_from]) > 0:  # if they have any viewables at all
                    received_message = viewables[next_receiver][receiving_from][0]
                    try:
                        validators[next_receiver].receive_consensus_message(received_message)
                        viewables[next_receiver][receiving_from].remove(received_message)
                        new_received = True
                    except UnresolvedDeps:
                        pass

        # RECEIVE CONSENSUS MESSAGES BETWEEN SHARDS
        for j in range(NUM_BETWEEN_SHARD_RECEIPTS_PER_ROUND):

            pool = copy.copy(VALIDATOR_NAMES)
            pool.remove(0)

            next_receiver = random.choice(pool)
            pool.remove(next_receiver)

            new_received = False
            while(not new_received and len(pool) > 0):

                receiving_from = random.choice(pool)
                pool.remove(receiving_from)

                if len(viewables[next_receiver][receiving_from]) > 0:  # if they have any viewables at all
                    received_message = viewables[next_receiver][receiving_from][0]  # receive the next one in the list
                    try:
                        validators[next_receiver].receive_consensus_message(received_message)
                        viewables[next_receiver][receiving_from].remove(received_message)
                        new_received = True
                    except UnresolvedDeps:
                        pass

    # REPORTING:
    print("Step: ", i)
    if not REPORTING:
        continue
    if (i + 1) % REPORT_INTERVAL == 0:
        report(watcher)