def get(request, block_identifier):
"""
description: List confirmation block chain segment (starting at the block_identifier)
"""
if len(block_identifier) != HEAD_HASH_LENGTH:
return Response(
{
ERROR:
f'block_identifier must be {HEAD_HASH_LENGTH} characters long'
},
status=status.HTTP_403_FORBIDDEN)
confirmation_block_cache_key = get_confirmation_block_cache_key(
block_identifier=block_identifier)
confirmation_block = cache.get(confirmation_block_cache_key)
if not confirmation_block:
return Response(status=status.HTTP_404_NOT_FOUND)
counter = 0
results = []
while confirmation_block and counter < settings.CONFIRMATION_BLOCK_CHAIN_SEGMENT_LENGTH:
results.append(confirmation_block)
message = confirmation_block['message']
message_hash = get_message_hash(message=message)
confirmation_block_cache_key = get_confirmation_block_cache_key(
block_identifier=message_hash)
confirmation_block = cache.get(confirmation_block_cache_key)
counter += 1
return Response(results)
def sign_block_to_confirm_and_update_head_block_hash(*, block, existing_accounts, new_accounts):
"""
Sign block to confirm validity
Update HEAD_BLOCK_HASH
"""
try:
head_block_hash = cache.get(HEAD_BLOCK_HASH)
message = {
'block': block,
'block_identifier': head_block_hash,
'updated_balances': format_updated_balances(existing_accounts, new_accounts)
}
confirmation_block = generate_signed_request(
data=message,
nid_signing_key=get_signing_key()
)
message_hash = get_message_hash(message=message)
cache.set(HEAD_BLOCK_HASH, message_hash, None)
return confirmation_block, message_hash
except Exception as e:
capture_exception(e)
logger.exception(e)
def get_updated_accounts(*, sender_account_balance, validated_block):
"""Return the updated balances of all accounts involved"""
existing_accounts = []
new_accounts = []
message = validated_block['message']
txs = message['txs']
total_amount = sum([tx['amount'] for tx in txs])
existing_accounts.append({
'account_number': validated_block['account_number'],
'balance': sender_account_balance - total_amount,
'balance_lock': get_message_hash(message=message)
})
for tx in txs:
amount = tx['amount']
recipient = tx['recipient']
recipient_account_balance = get_account_balance(account_number=recipient)
if recipient_account_balance is None:
new_accounts.append({
'account_number': recipient,
'balance': amount
})
else:
existing_accounts.append({
'account_number': recipient,
'balance': recipient_account_balance + amount
})
return existing_accounts, new_accounts
def send_confirmation_block_history(*, block_identifier, ip_address, port,
protocol):
"""
Send historical confirmation blocks (starting with the block_identifier) to the confirmation validator
"""
address = format_address(ip_address=ip_address,
port=port,
protocol=protocol)
url = f'{address}/confirmation_blocks'
valid_confirmation_block = get_valid_confirmation_block(
block_identifier=block_identifier)
while valid_confirmation_block:
try:
post(url=url, body=valid_confirmation_block)
except Exception as e:
capture_exception(e)
logger.exception(e)
block_identifier = get_message_hash(
message=valid_confirmation_block['message'])
valid_confirmation_block = get_valid_confirmation_block(
block_identifier=block_identifier)
def get_initial_block_identifier(self, primary_validator_config):
"""
Return initial block identifier
If seed_block_identifier, fetch related (seed) block and hash to get initial block identifier
Otherwise, return root_account_file_hash
"""
seed_block_identifier = primary_validator_config.get(
'seed_block_identifier')
if not seed_block_identifier:
self_configuration = get_self_configuration(
exception_class=RuntimeError)
root_account_file_hash = self_configuration.root_account_file_hash
pv_root_account_file_hash = primary_validator_config.get(
'root_account_file_hash')
if root_account_file_hash != pv_root_account_file_hash:
self._error(
'SelfConfiguration.root_account_file_hash does not match primary validator root_account_file_hash'
)
self._error(f'SelfConfiguration: {root_account_file_hash}')
self._error(f'Primary validator: {pv_root_account_file_hash}')
raise RuntimeError()
return root_account_file_hash
address = self.get_primary_validator_address()
confirmation_block = get_confirmation_block(
address=address, block_identifier=seed_block_identifier)
return get_message_hash(message=confirmation_block['message'])
def populate_confirmation_block_queue(*, address, error_handler,
initial_block_identifier):
"""
Fetch confirmation blocks from primary validator starting with initial_block_identifier
Add all confirmation blocks to confirmation block queue
"""
block_identifier = initial_block_identifier
results = get_confirmation_block_chain_segment(
address=address, block_identifier=block_identifier)
error = False
while results and not error:
confirmation_block = get_confirmation_block_from_results(
block_identifier=block_identifier, results=results)
while confirmation_block:
message = confirmation_block['message']
try:
verify_signature(
message=sort_and_encode(message),
signature=confirmation_block['signature'],
verify_key=confirmation_block['node_identifier'])
except BadSignatureError as e:
error_handler(e)
error = True
break
except Exception as e:
error_handler(e)
error = True
break
serializer = ConfirmationBlockSerializerCreate(data=message)
if serializer.is_valid():
_bid = serializer.save()
print(_bid)
else:
error_handler(serializer.errors)
error = True
break
block_identifier = get_message_hash(message=message)
confirmation_block = get_confirmation_block_from_results(
block_identifier=block_identifier, results=results)
if error:
break
results = get_confirmation_block_chain_segment(
address=address, block_identifier=block_identifier)
def get_initial_block_identifier():
"""
Return initial block identifier
If seed_block_identifier, fetch related (seed) block and hash to get initial block identifier
Otherwise, return root_account_file_hash
"""
self_configuration = get_self_configuration(exception_class=RuntimeError)
seed_block_identifier = self_configuration.seed_block_identifier
if seed_block_identifier:
confirmation_block_cache_key = get_confirmation_block_cache_key(
block_identifier=seed_block_identifier)
confirmation_block = cache.get(confirmation_block_cache_key)
return get_message_hash(message=confirmation_block['message'])
return self_configuration.root_account_file_hash
def confirmation_block_data(block_data, block_identifier,
primary_validator_signing_key, account_number):
yield generate_signed_request(
data={
'block':
block_data,
'block_identifier':
block_identifier,
'updated_balances': [{
'account_number':
block_data['account_number'],
'balance':
1,
'balance_lock':
get_message_hash(message=block_data['message']),
}],
},
nid_signing_key=primary_validator_signing_key,
)
def send_block_to_bank(block):
"""
Send block to bank
"""
next_balance_lock = get_message_hash(message=block['message'])
print(f'\nNext balance lock will be: {next_balance_lock}\n')
bank_address = format_address(ip_address='167.99.173.247',
port=None,
protocol='http')
url = f'{bank_address}/blocks'
results = post(url=url, body=block)
if isinstance(results, dict):
for k, v in results.items():
print(f'{k}: {v}')
write_json(os.path.join(BLOCKS_DIR, 'blocks-response.json'), results)
def block_chain_view(_):
"""
Return block chain
"""
block_chain = {}
initial_block_identifier = get_initial_block_identifier()
block_identifier = initial_block_identifier
valid_confirmation_block = get_valid_confirmation_block(block_identifier=block_identifier)
i = 0
while valid_confirmation_block:
block_chain[i] = valid_confirmation_block
block_identifier = get_message_hash(message=valid_confirmation_block['message'])
valid_confirmation_block = get_valid_confirmation_block(block_identifier=block_identifier)
i += 1
return Response({
'initial_block_identifier': initial_block_identifier,
'block_chain': block_chain
})
def block_chain_view(_):
"""
Return block chain
"""
block_chain = {}
initial_block_identifier = get_initial_block_identifier()
block_identifier = initial_block_identifier
confirmation_block_cache_key = get_confirmation_block_cache_key(block_identifier=block_identifier)
confirmation_block = cache.get(confirmation_block_cache_key)
i = 0
while confirmation_block:
block_chain[i] = confirmation_block
block_identifier = get_message_hash(message=confirmation_block['message'])
confirmation_block_cache_key = get_confirmation_block_cache_key(block_identifier=block_identifier)
confirmation_block = cache.get(confirmation_block_cache_key)
i += 1
return Response({
'initial_block_identifier': initial_block_identifier,
'block_chain': block_chain
})