def get_balance():
if not blockchain.has_wallet:
message = get_message(HttpMethods.GET, False, 'balance')
return Response({'funds': 0, 'hasOwner': False}, message, 500).get()
message = message = get_message(HttpMethods.GET, True, 'balance')
return Response({'funds': blockchain.balance, 'hasOwner': True}, message, 200).get()
def get_nodes():
""" Returns all peer nodes associated with blockchain """
all_nodes = blockchain.peer_nodes
if all_nodes is None:
return Response({'nodes': None}, get_message(HttpMethods.GET, False, 'node'), 500).get()
return Response({'nodes': get_serializable_peer_nodes(blockchain.peer_nodes)}, get_message(HttpMethods.GET, True, 'node'), 200).get()
def load_wallet():
blockchain.load_wallet()
if blockchain.has_wallet:
message = get_message(HttpMethods.GET, True, 'wallet')
return Response({'public_key': blockchain.owner, 'savedWallet': True}, message, 200).get()
message = get_message(HttpMethods.GET, False, 'wallet')
return Response({'public_key': blockchain.owner, 'savedWallet': False}, message, 500).get()
def get_open_transactions():
if not blockchain.has_wallet:
message = get_message(HttpMethods.GET, False,
'open transaction', additional_info='No Wallet found!')
return Response({'open_transactions': None}, message, 500).get()
message = get_message(HttpMethods.GET, True, 'open transaction', )
return Response({'open_transactions': get_serializable_transaction(blockchain.open_transactions)}, message, 200).get()
def ensure_wallet(blockchain: Blockchain, *,
action_subject: str) -> Union[None, Response]:
""" Handles Response for Requests with missing wallet """
if not blockchain.has_wallet:
message = get_message(HttpMethods.POST,
False,
action_subject,
additional_info='No Wallet found!')
return Response({action_subject: None}, message, 500).get()
def ensure_tx_appended(add_transaction_success: bool) -> Union[None, Response]:
if not add_transaction_success:
message = get_message(HttpMethods.POST, False, 'transaction')
return Response(
{
'transaction': None,
'missing_fields': None,
"transactions_synced": False
}, message, 500).get()
def resolve_conflicts():
blockchain_replaced = blockchain.resolve_conflicts()
if blockchain_replaced:
blockchain.has_conflicts = False
conflict_message = 'Conflict succesfully resolved.' if blockchain_replaced else 'No Conflict found. Blockchain unchanged.'
message = get_message(HttpMethods.POST, blockchain_replaced,
'conflict', additional_info=conflict_message)
return Response({'conflictResolved': blockchain_replaced}, message, HttpStatusCodes.SUCCESS).get()
def delete_node(peer_node: str):
""" Deletes a node from the blockchain peer nodes """
node_to_delete = peer_node
if not len(node_to_delete):
return Response({'nodes': get_serializable_peer_nodes(blockchain.peer_nodes)}, get_message(HttpMethods.DELETE, False, 'node', additional_info='Please provide a valid node to delete.'), 400).get()
if not node_to_delete in blockchain.peer_nodes:
return Response({'node': get_serializable_peer_nodes(blockchain.peer_nodes)}, get_message(HttpMethods.DELETE, False, 'node', additional_info=f'Delete peer node {node_to_delete} failed. No peer node found!'), 500).get()
blockchain.remove_peer_node(node_to_delete)
return Response({'nodes': get_serializable_peer_nodes(blockchain.peer_nodes)}, get_message(HttpMethods.DELETE, True, 'node'), 200).get()
def create_node():
""" Adds a node to the blockchain peer nodes """
body: Dict = request.get_json()
node_to_add = body.get('node')
if not body or not node_to_add:
return Response({'nodes': get_serializable_peer_nodes(blockchain.peer_nodes)}, get_message(HttpMethods.POST, False, 'node', additional_info='Please provide a valid node to add.'), 400).get()
if blockchain.add_peer_node(node_to_add):
return Response({'node': get_serializable_peer_nodes(blockchain.peer_nodes)}, get_message(HttpMethods.POST, True, 'node'), 200).get()
return Response({'nodes': get_serializable_peer_nodes(blockchain.peer_nodes)}, get_message(HttpMethods.POST, False, 'node', additional_info=f'Saving peer node {node_to_add} failed!'), 400).get()
def mine():
if blockchain.has_conflicts:
message = get_message(HttpMethods.POST, False,
'block', additional_info='Conflict: Please resolve the conflict first!')
return Response({'blockSynced': False, 'conflict': True}, message, HttpStatusCodes.CONFLICT).get()
try:
mining_successful = blockchain.mine()
created_block = blockchain.latest_block
if mining_successful and created_block:
blockSyncer = BlockSync(blockchain.peer_nodes)
broadcast_tx_succes, has_conflicts = blockSyncer.broadcast(
created_block)
blockchain.has_conflicts = has_conflicts
return Response({'block': get_serializable_block(created_block), 'blockSynced': broadcast_tx_succes, 'conflict': blockchain.has_conflicts}, get_message(HttpMethods.POST, True, 'block'), HttpStatusCodes.SUCCESS).get() if mining_successful else Response({'error': True}, get_message(HttpMethods.POST, False, 'block'), 400).get()
except Exception as error:
message = get_message(HttpMethods.POST, False,
'block', additional_info=f'(Error: {error})')
return Response({'blockSynced': False}, message, HttpStatusCodes.SERVER_ERROR).get()
def broadcast_transactions():
transaction_data: Union(Dict, None) = request.get_json()
ensure_required_fields(transaction_data, RequiredFields.get_required_fields(BlockchainEndpoints.TRANSACTION),
action_subject='broadcast transaction')
ensure_tx_appended(blockchain.add_transaction(
**transaction_data, is_broadcast_tx=True))
message = get_message(HttpMethods.POST,
True, 'broadcast transaction')
return Response({'transaction': get_serializable_transaction(blockchain.latest_transaction), 'missing_fields': None, "transactions_synced": True}, message, 200).get()
def broadcast_block():
block_data: Union(Dict, None) = request.get_json()
ensure_required_fields(block_data, RequiredFields.get_required_fields(BlockchainEndpoints.BROADCAST_BLOCK),
action_subject='broadcast block')
broadcast_block = block_from_deserialized_block(block_data['block'])
successMessage = get_message(HttpMethods.POST, True, 'broadcast block')
errorMessage = get_message(HttpMethods.POST, False, 'broadcast block')
if is_next_block(blockchain, broadcast_block):
blockchain_added = blockchain.add_block(broadcast_block)
if blockchain_added:
return Response({}, successMessage, 200).get()
return Response({}, errorMessage, 400).get()
elif is_future_block(blockchain, broadcast_block):
blockchain.has_conflicts = True
return Response({}, errorMessage, 200).get()
elif is_previous_block(blockchain, broadcast_block):
return Response({}, errorMessage, HttpStatusCodes.CONFLICT).get()
def add_transaction():
ensure_wallet(blockchain, action_subject='transaction')
transaction_data: Union(Dict, None) = request.get_json()
ensure_required_fields(transaction_data, RequiredFields.get_required_fields(BlockchainEndpoints.TRANSACTION),
action_subject='transaction')
ensure_tx_appended(blockchain.add_transaction(**transaction_data))
tx_syncer = TransactionSync(blockchain.peer_nodes)
broadcast_tx_succes, _ = tx_syncer.broadcast(
blockchain.latest_transaction)
message = get_message(HttpMethods.POST,
True, 'transaction')
return Response({'transaction': get_serializable_transaction(blockchain.latest_transaction), 'missing_fields': None, "transactions_synced": broadcast_tx_succes}, message, 200).get()
def ensure_required_fields(data: Union[Dict, None], required_fields: List[str],
*, action_subject: str) -> Union[None, Response]:
""" Handles Response for Requests with missing fields """
if not has_all_required_fields(data, required_fields):
missing_fields = get_missing_fields(data, required_fields)
missing_fields_stringified = ', '.join(missing_fields)
message = get_message(
HttpMethods.POST,
False,
action_subject,
additional_info=
f'Please Provide complete {action_subject}. Missing Fields: {missing_fields_stringified}'
)
return Response(
{
action_subject: None,
'missing_fields': missing_fields,
"transactions_synced": False
}, message, 400).get()
def create_wallet():
saved = False
error = False
try:
_, private_key = blockchain.create_wallet()
except:
error = True
should_save = get_param(request, 'save')
if(should_save and not error):
try:
saved = blockchain.save_wallet()
except:
error = True
success = error is False
message = get_message(HttpMethods.POST, success, 'wallet')
status = 201 if success else 500
return Response({'public_key': blockchain.owner, 'private_key': private_key, 'savedWallet': saved}, message, status).get()