initial implementation of multi input support

bigchaindb/consensus.py

@@ -119,7 +119,7 @@ class BaseConsensusRules(AbstractConsensusRules):
         # If the operation is CREATE the transaction should have no inputs and
         # should be signed by a federation node
         if transaction['transaction']['operation'] == 'CREATE':
-            if transaction['transaction']['input']:
+            if transaction['transaction']['inputs']:
                 raise ValueError('A CREATE operation has no inputs')
             if transaction['transaction']['current_owner'] not in (
                     bigchain.federation_nodes + [bigchain.me]):
@@ -128,32 +128,32 @@ class BaseConsensusRules(AbstractConsensusRules):
 
         else:
             # check if the input exists, is owned by the current_owner
-            if not transaction['transaction']['input']:
+            if not transaction['transaction']['inputs']:
                 raise ValueError(
                     'Only `CREATE` transactions can have null inputs')
 
-            tx_input = bigchain.get_transaction(
-                transaction['transaction']['input'])
+            # check inputs
+            for inp in transaction['transaction']['inputs']:
+                tx_input = bigchain.get_transaction(inp)
 
-            if not tx_input:
-                raise exceptions.TransactionDoesNotExist(
-                    'input `{}` does not exist in the bigchain'.format(
-                        transaction['transaction']['input']))
+                if not tx_input:
+                    raise exceptions.TransactionDoesNotExist(
+                        'input `{}` does not exist in the bigchain'.format(
+                            transaction['transaction']['input']))
 
-            if (tx_input['transaction']['new_owner'] !=
-                transaction['transaction']['current_owner']):
-                raise exceptions.TransactionOwnerError(
-                    'current_owner `{}` does not own the input `{}`'.format(
-                        transaction['transaction']['current_owner'],
-                        transaction['transaction']['input']))
+                if (tx_input['transaction']['new_owner'] !=
+                    transaction['transaction']['current_owner']):
+                    raise exceptions.TransactionOwnerError(
+                        'current_owner `{}` does not own the input `{}`'.format(
+                            transaction['transaction']['current_owner'],
+                            transaction['transaction']['input']))
 
-            # check if the input was already spent by a transaction other than
-            # this one.
-            spent = bigchain.get_spent(tx_input['id'])
-            if spent and spent['id'] != transaction['id']:
-                raise exceptions.DoubleSpend(
-                    'input `{}` was already spent'.format(
-                        transaction['transaction']['input']))
+                # check if the input was already spent by a transaction other than
+                # this one.
+                spent = bigchain.get_spent(tx_input['id'])
+                if spent and spent['id'] != transaction['id']:
+                    raise exceptions.DoubleSpend(
+                        'input `{}` was already spent'.format(inp))
 
         # Check hash of the transaction
         calculated_hash = hash_data(util.serialize(

bigchaindb/core.py

@@ -203,7 +203,7 @@ class Bigchain(object):
         # checks if an input was already spent
         # checks if the bigchain has any transaction with input `transaction_id`
         response = r.table('bigchain').concat_map(lambda doc: doc['block']['transactions'])\
-            .filter(lambda transaction: transaction['transaction']['input'] == txid).run(self.conn)
+            .filter(lambda transaction: transaction['transaction']['inputs'].contains(txid)).run(self.conn)
 
         # a transaction_id should have been spent at most one time
         transactions = list(response)

bigchaindb/util.py

@@ -76,7 +76,7 @@ def timestamp():
     return "{0:.6f}".format(time.mktime(dt.timetuple()) + dt.microsecond / 1e6)
 
 
-def create_tx(current_owner, new_owner, tx_input, operation, payload=None):
+def create_tx(current_owner, new_owner, inputs, operation, payload=None):
     """Create a new transaction
 
     A transaction in the bigchain is a transfer of a digital asset between two entities represented
@@ -94,7 +94,7 @@ def create_tx(current_owner, new_owner, tx_input, operation, payload=None):
     Args:
         current_owner (str): base58 encoded public key of the current owner of the asset.
         new_owner (str): base58 encoded public key of the new owner of the digital asset.
-        tx_input (str): id of the transaction to use as input.
+        inputs (list): id of the transaction to use as input.
         operation (str): Either `CREATE` or `TRANSFER` operation.
         payload (Optional[dict]): dictionary with information about asset.
 
@@ -106,6 +106,7 @@ def create_tx(current_owner, new_owner, tx_input, operation, payload=None):
         TypeError: if the optional ``payload`` argument is not a ``dict``.
     """
 
+    # handle payload
     data = None
     if payload is not None:
         if isinstance(payload, dict):
@@ -123,10 +124,13 @@ def create_tx(current_owner, new_owner, tx_input, operation, payload=None):
         'payload': payload
     }
 
+    if inputs == []:
+        inputs = None
+
     tx = {
         'current_owner': current_owner,
         'new_owner': new_owner,
-        'input': tx_input,
+        'inputs': inputs,
         'operation': operation,
         'timestamp': timestamp(),
         'data': data

tests/db/test_bigchain_api.py

@@ -756,3 +756,16 @@ class TestBigchainBlock(object):
 
     def test_duplicated_transactions(self):
         pytest.skip('We may have duplicates in the initial_results and changefeed')
+
+
+class TestMultipleInputs(object):
+
+    def test_transfer_transaction_multiple(self, b):
+        pass
+
+    def test_transfer_single_input_from_multi_input(self, b):
+        pass
+
+    def test_get_spent(self, b):
+        pass
+