address vrde's comments, reshuffle some exceptions around

bigchaindb/backend/exceptions.py

@@ -15,11 +15,3 @@ class OperationError(BackendError):
 
 class DuplicateKeyError(OperationError):
     """Exception raised when an insert fails because the key is not unique"""
-
-
-class CriticalDoubleSpend(BigchainDBError):
-    """Data integrity error that requires attention"""
-
-
-class CriticalDoubleInclusion(BigchainDBError):
-    """Data integrity error that requires attention"""

bigchaindb/common/exceptions.py

@@ -92,8 +92,8 @@ class AmountError(ValidationError):
     """Raised when there is a problem with a transaction's output amounts"""
 
 
-class TransactionDoesNotExist(ValidationError):
-    """Raised if the transaction is not in the database"""
+class InputDoesNotExist(ValidationError):
+    """Raised if a transaction input does not exist"""
 
 
 class TransactionOwnerError(ValidationError):

bigchaindb/core.py

@@ -4,6 +4,7 @@ import collections
 from time import time
 
 from itertools import compress
+from bigchaindb import exceptions as core_exceptions
 from bigchaindb.common import crypto, exceptions
 from bigchaindb.common.utils import gen_timestamp, serialize
 from bigchaindb.common.transaction import TransactionLink
@@ -11,7 +12,6 @@ from bigchaindb.common.transaction import TransactionLink
 import bigchaindb
 
 from bigchaindb import backend, config_utils, utils
-from bigchaindb.backend import exceptions as backend_exceptions
 from bigchaindb.consensus import BaseConsensusRules
 from bigchaindb.models import Block, Transaction
 
@@ -308,7 +308,7 @@ class Bigchain(object):
             if list(validity.values()).count(Bigchain.BLOCK_VALID) > 1:
                 block_ids = str([block for block in validity
                                  if validity[block] == Bigchain.BLOCK_VALID])
-                raise backend_exceptions.CriticalDoubleInclusion(
+                raise core_exceptions.CriticalDoubleInclusion(
                     'Transaction {tx} is present in '
                     'multiple valid blocks: {block_ids}'
                     .format(tx=txid, block_ids=block_ids))
@@ -361,7 +361,7 @@ class Bigchain(object):
                 if self.get_transaction(transaction['id']):
                     num_valid_transactions += 1
                 if num_valid_transactions > 1:
-                    raise backend_exceptions.CriticalDoubleSpend(
+                    raise core_exceptions.CriticalDoubleSpend(
                         '`{}` was spent more than once. There is a problem'
                         ' with the chain'.format(txid))
 

bigchaindb/exceptions.py

@@ -1,2 +1,10 @@
 class BigchainDBError(Exception):
     """Base class for BigchainDB exceptions."""
+
+
+class CriticalDoubleSpend(BigchainDBError):
+    """Data integrity error that requires attention"""
+
+
+class CriticalDoubleInclusion(BigchainDBError):
+    """Data integrity error that requires attention"""

bigchaindb/models.py

@@ -1,6 +1,6 @@
 from bigchaindb.common.crypto import hash_data, PublicKey, PrivateKey
 from bigchaindb.common.exceptions import (InvalidHash, InvalidSignature,
-                                          DoubleSpend, TransactionDoesNotExist,
+                                          DoubleSpend, InputDoesNotExist,
                                           TransactionNotInValidBlock,
                                           AssetIdMismatch, AmountError,
                                           SybilError, ValidationError)
@@ -60,8 +60,8 @@ class Transaction(Transaction):
                     get_transaction(input_txid, include_status=True)
 
                 if input_tx is None:
-                    raise TransactionDoesNotExist("input `{}` doesn't exist"
-                                                  .format(input_txid))
+                    raise InputDoesNotExist("input `{}` doesn't exist"
+                                            .format(input_txid))
 
                 if status != bigchain.TX_VALID:
                     raise TransactionNotInValidBlock(

tests/db/test_bigchain_api.py

@@ -93,7 +93,7 @@ class TestBigchainApi(object):
 
     @pytest.mark.genesis
     def test_get_spent_with_double_inclusion_detected(self, b, monkeypatch):
-        from bigchaindb.backend.exceptions import CriticalDoubleInclusion
+        from bigchaindb.exceptions import CriticalDoubleInclusion
         from bigchaindb.models import Transaction
 
         tx = Transaction.create([b.me], [([b.me], 1)])
@@ -128,7 +128,7 @@ class TestBigchainApi(object):
 
     @pytest.mark.genesis
     def test_get_spent_with_double_spend_detected(self, b, monkeypatch):
-        from bigchaindb.backend.exceptions import CriticalDoubleSpend
+        from bigchaindb.exceptions import CriticalDoubleSpend
         from bigchaindb.models import Transaction
 
         tx = Transaction.create([b.me], [([b.me], 1)])
@@ -163,7 +163,7 @@ class TestBigchainApi(object):
 
     @pytest.mark.genesis
     def test_get_block_status_for_tx_with_double_inclusion(self, b, monkeypatch):
-        from bigchaindb.backend.exceptions import CriticalDoubleInclusion
+        from bigchaindb.exceptions import CriticalDoubleInclusion
         from bigchaindb.models import Transaction
 
         tx = Transaction.create([b.me], [([b.me], 1)])