1.0.0b5

setup.py

@@ -28,7 +28,7 @@
   name        = 'PyOTA',
   description = 'IOTA API library for Python',
   url         = 'https://github.com/iotaledger/iota.lib.py',
-  version     = '1.0.0b4',
+  version     = '1.0.0b5',
 
   packages              = find_packages('src'),
   include_package_data  = True,

src/iota/api.py

@@ -461,22 +461,23 @@ def get_latest_inclusion(self, hashes):
     """
     return self.getLatestInclusion(hashes=hashes)
 
-  def get_new_addresses(self, index=None, count=1):
-    # type: (Optional[int], Optional[int]) -> List[Address]
+  def get_new_addresses(self, index=0, count=1):
+    # type: (int, Optional[int]) -> List[Address]
     """
     Generates one or more new addresses from the seed.
 
     :param index:
       Specify the index of the new address (must be >= 1).
 
-      If not provided, the address will be generated deterministically.
-
     :param count:
       Number of addresses to generate (must be >= 1).
 
       Note: This is more efficient than calling ``get_new_address``
       inside a loop.
 
+      If ``None``, this method will scan the Tangle to find the next
+      available unused address and return that.
+
     :return:
       List of generated addresses.
 

src/iota/commands/extended/get_new_addresses.py

@@ -35,7 +35,7 @@ def _execute(self, request):
     index = request.get('index')
 
     # Required parameters.
-    seed  = request['seed']
+    seed = request['seed']
 
     generator = AddressGenerator(seed)
 

src/iota/crypto/signing.py

@@ -8,7 +8,7 @@
 
 from iota import TRITS_PER_TRYTE, TryteString, TrytesCompatible, Hash
 from iota.crypto import Curl, FRAGMENT_LENGTH, HASH_LENGTH
-from iota.crypto.types import PrivateKey
+from iota.crypto.types import PrivateKey, Seed
 from iota.exceptions import with_context
 
 __all__ = [
@@ -68,7 +68,7 @@ def __init__(self, seed):
     # type: (TrytesCompatible) -> None
     super(KeyGenerator, self).__init__()
 
-    self.seed = TryteString(seed)
+    self.seed = Seed(seed)
 
   def get_keys(self, start, count=1, step=1, iterations=1):
     # type: (int, int, int, int) -> List[PrivateKey]

src/iota/crypto/types.py

@@ -87,14 +87,15 @@ def get_digest_trits(self):
     """
     hashes_per_fragment = FRAGMENT_LENGTH // Hash.LEN
 
-    digest = [0] * HASH_LENGTH
+    key_chunks = self.iter_chunks(FRAGMENT_LENGTH)
 
-    for (i, fragment) in enumerate(self.iter_chunks(FRAGMENT_LENGTH)): # type: Tuple[int, TryteString]
-      fragment_start  = i * FRAGMENT_LENGTH
-      fragment_end    = fragment_start + FRAGMENT_LENGTH
-      fragment_trits  = fragment[fragment_start:fragment_end].as_trits()
+    # The digest will contain one hash per key fragment.
+    digest = [0] * HASH_LENGTH * len(key_chunks)
+
+    for (i, fragment) in enumerate(key_chunks): # type: Tuple[int, TryteString]
+      fragment_trits = fragment.as_trits()
 
-      key_fragment  = [0] * len(fragment_trits)
+      key_fragment  = [0] * FRAGMENT_LENGTH
       hash_trits    = []
 
       for j in range(hashes_per_fragment):
@@ -113,6 +114,9 @@ def get_digest_trits(self):
       sponge.absorb(key_fragment)
       sponge.squeeze(hash_trits)
 
+      fragment_start  = i * FRAGMENT_LENGTH
+      fragment_end    = fragment_start + FRAGMENT_LENGTH
+
       digest[fragment_start:fragment_end] = hash_trits
 
     return digest

src/iota/transaction.py

@@ -15,6 +15,7 @@
   validate_signature_fragments
 from iota.exceptions import with_context
 from iota.json import JsonSerializable
+from six import PY2
 
 __all__ = [
   'Bundle',
@@ -127,51 +128,51 @@ def __init__(
       branch_transaction_hash,
       nonce,
   ):
-    # type: (Optional[TransactionHash], Optional[TryteString], Address, int, Tag, int, Optional[int], Optional[int], Optional[BundleHash], Optional[TransactionHash], Optional[TransactionHash], Optional[Hash]) -> None
-    self.hash = hash_
+    # type: (Optional[TransactionHash], Optional[Fragment], Address, int, Optional[Tag], int, Optional[int], Optional[int], Optional[BundleHash], Optional[TransactionHash], Optional[TransactionHash], Optional[Hash]) -> None
+    self.hash = hash_ # type: Optional[TransactionHash]
     """
     Transaction ID, generated by taking a hash of the transaction
     trits.
     """
 
-    self.bundle_hash = bundle_hash
+    self.bundle_hash = bundle_hash # type: Optional[BundleHash]
     """
     Bundle hash, generated by taking a hash of metadata from all the
     transactions in the bundle.
     """
 
-    self.address = address
+    self.address = address # type: Address
     """
     The address associated with this transaction.
     If ``value`` is != 0, the associated address' balance is adjusted
     as a result of this transaction.
     """
 
-    self.value = value
+    self.value = value # type: int
     """
     Amount to adjust the balance of ``address``.
     Can be negative (i.e., for spending inputs).
     """
 
-    self.tag = tag
+    self.tag = tag # type: Optional[Tag]
     """
     Optional classification tag applied to this transaction.
     """
 
-    self.nonce = nonce
+    self.nonce = nonce # type: Optional[Hash]
     """
     Unique value used to increase security of the transaction hash.
     """
 
-    self.timestamp = timestamp
+    self.timestamp = timestamp # type: int
     """
     Timestamp used to increase the security of the transaction hash.
 
     IMPORTANT: This value is easy to forge!
     Do not rely on it when resolving conflicts!
     """
 
-    self.current_index = current_index
+    self.current_index = current_index # type: Optional[int]
     """
     The position of the transaction inside the bundle.
 
@@ -180,12 +181,12 @@ def __init__(
     last.
     """
 
-    self.last_index = last_index
+    self.last_index = last_index # type: Optional[int]
     """
     The position of the final transaction inside the bundle.
     """
 
-    self.trunk_transaction_hash = trunk_transaction_hash
+    self.trunk_transaction_hash = trunk_transaction_hash # type: Optional[TransactionHash]
     """
     In order to add a transaction to the Tangle, you must perform PoW
     to "approve" two existing transactions, called the "trunk" and
@@ -195,7 +196,7 @@ def __init__(
     a bundle.
     """
 
-    self.branch_transaction_hash = branch_transaction_hash
+    self.branch_transaction_hash = branch_transaction_hash # type: Optional[TransactionHash]
     """
     In order to add a transaction to the Tangle, you must perform PoW
     to "approve" two existing transactions, called the "trunk" and
@@ -204,7 +205,7 @@ def __init__(
     The branch transaction generally has no significance.
     """
 
-    self.signature_message_fragment = signature_message_fragment
+    self.signature_message_fragment = signature_message_fragment # type: Optional[Fragment]
     """
     "Signature/Message Fragment" (note the slash):
 
@@ -676,19 +677,34 @@ class ProposedBundle(JsonSerializable, Sequence[ProposedTransaction]):
   A collection of proposed transactions, to be treated as an atomic
   unit when attached to the Tangle.
   """
-  def __init__(self, transactions=None):
-    # type: (Optional[Iterable[ProposedTransaction]]) -> None
+  def __init__(self, transactions=None, inputs=None, change_address=None):
+    # type: (Optional[Iterable[ProposedTransaction]], Optional[Iterable[Address]], Optional[Address]) -> None
     super(ProposedBundle, self).__init__()
 
     self.hash = None # type: Optional[Hash]
-    self.tag  = None # type: Optional[Tag]
 
     self._transactions = [] # type: List[ProposedTransaction]
 
     if transactions:
       for t in transactions:
         self.add_transaction(t)
 
+    if inputs:
+      self.add_inputs(inputs)
+
+    self.change_address = change_address
+
+  def __bool__(self):
+    # type: () -> bool
+    """
+    Returns whether this bundle has any transactions.
+    """
+    return bool(self._transactions)
+
+  # :bc: Magic methods have different names in Python 2.
+  if PY2:
+    __nonzero__ = __bool__
+
   def __contains__(self, transaction):
     # type: (ProposedTransaction) -> bool
     return transaction in self._transactions
@@ -730,6 +746,19 @@ def balance(self):
     """
     return sum(t.value for t in self._transactions)
 
+  @property
+  def tag(self):
+    # type: () -> Tag
+    """
+    Determines the most relevant tag for the bundle.
+    """
+    for txn in reversed(self): # type: ProposedTransaction
+      if txn.tag:
+        # noinspection PyTypeChecker
+        return txn.tag
+
+    return Tag(b'')
+
   def as_json_compatible(self):
     # type: () -> List[dict]
     """
@@ -762,6 +791,9 @@ def add_transaction(self, transaction):
     if self.hash:
       raise RuntimeError('Bundle is already finalized.')
 
+    if transaction.value < 0:
+      raise ValueError('Use ``add_inputs`` to add inputs to the bundle.')
+
     self._transactions.append(ProposedTransaction(
       address   = transaction.address,
       value     = transaction.value,
@@ -770,9 +802,6 @@ def add_transaction(self, transaction):
       timestamp = transaction.timestamp,
     ))
 
-    # Last-added transaction determines the bundle tag.
-    self.tag = transaction.tag or self.tag
-
     # If the message is too long to fit in a single transactions,
     # it must be split up into multiple transactions so that it will
     # fit.
@@ -835,7 +864,7 @@ def add_inputs(self, inputs):
         )
 
       # Add the input as a transaction.
-      self.add_transaction(ProposedTransaction(
+      self._transactions.append(ProposedTransaction(
         address = addy,
         tag     = self.tag,
 
@@ -848,7 +877,7 @@ def add_inputs(self, inputs):
       # transaction length limit.
       # Subtract 1 to account for the transaction we just added.
       for _ in range(AddressGenerator.DIGEST_ITERATIONS - 1):
-        self.add_transaction(ProposedTransaction(
+        self._transactions.append(ProposedTransaction(
           address = addy,
           tag     = self.tag,
 
@@ -867,16 +896,7 @@ def send_unspent_inputs_to(self, address):
     if self.hash:
       raise RuntimeError('Bundle is already finalized.')
 
-    # Negative balance means that there are unspent inputs.
-    # See :py:meth:`balance` for more info.
-    unspent_inputs = -self.balance
-
-    if unspent_inputs > 0:
-      self.add_transaction(ProposedTransaction(
-        address = address,
-        value   = unspent_inputs,
-        tag     = self.tag,
-      ))
+    self.change_address = address
 
   def finalize(self):
     # type: () -> None
@@ -886,21 +906,34 @@ def finalize(self):
     if self.hash:
       raise RuntimeError('Bundle is already finalized.')
 
+    if not self:
+      raise ValueError('Bundle has no transactions.')
+
     # Quick validation.
     balance = self.balance
-    if balance > 0:
+
+    if balance < 0:
+      if self.change_address:
+        self.add_transaction(ProposedTransaction(
+          address = self.change_address,
+          value   = -balance,
+          tag     = self.tag,
+        ))
+      else:
+        raise ValueError(
+          'Bundle has unspent inputs (balance: {balance}); '
+          'use ``send_unspent_inputs_to`` to create '
+          'change transaction.'.format(
+            balance = balance,
+          ),
+        )
+    elif balance > 0:
       raise ValueError(
         'Inputs are insufficient to cover bundle spend '
         '(balance: {balance}).'.format(
           balance = balance,
         ),
       )
-    elif balance < 0:
-      raise ValueError(
-        'Bundle has unspent inputs (balance: {balance}).'.format(
-          balance = balance,
-        ),
-      )
 
     # Generate bundle hash.
     sponge      = Curl()