break BigchainDBCritical into CriticalDoubleSpend and CriticalDoubleInclusion and add test

bigchaindb/backend/exceptions.py

@@ -17,5 +17,9 @@ class DuplicateKeyError(OperationError):
     """Exception raised when an insert fails because the key is not unique"""
 
 
-class BigchainDBCritical(Exception):
+class CriticalDoubleSpend(BigchainDBError):
-    """Unhandleable error that requires attention"""
+    """Data integrity error that requires attention"""
+
+
+class CriticalDoubleInclusion(BigchainDBError):
+    """Data integrity error that requires attention"""

bigchaindb/core.py

@@ -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.BigchainDBCritical(
+                raise backend_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 exceptions.BigchainDBCritical(
+                    raise backend_exceptions.CriticalDoubleSpend(
                         '`{}` was spent more than once. There is a problem'
                         ' with the chain'.format(txid))
 

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 BigchainDBCritical
+        from bigchaindb.backend.exceptions import CriticalDoubleInclusion
         from bigchaindb.models import Transaction
 
         tx = Transaction.create([b.me], [([b.me], 1)])
@@ -123,12 +123,47 @@ class TestBigchainApi(object):
         vote = b.vote(block3.id, b.get_last_voted_block().id, True)
         b.write_vote(vote)
 
-        with pytest.raises(BigchainDBCritical):
+        with pytest.raises(CriticalDoubleInclusion):
+            b.get_spent(tx.id, 0)
+
+    @pytest.mark.genesis
+    def test_get_spent_with_double_spend_detected(self, b, monkeypatch):
+        from bigchaindb.backend.exceptions import CriticalDoubleSpend
+        from bigchaindb.models import Transaction
+
+        tx = Transaction.create([b.me], [([b.me], 1)])
+        tx = tx.sign([b.me_private])
+
+        monkeypatch.setattr('time.time', lambda: 1000000000)
+        block1 = b.create_block([tx])
+        b.write_block(block1)
+
+        monkeypatch.setattr('time.time', lambda: 1000000020)
+        transfer_tx = Transaction.transfer(tx.to_inputs(), [([b.me], 1)],
+                                           asset_id=tx.id)
+        transfer_tx = transfer_tx.sign([b.me_private])
+        block2 = b.create_block([transfer_tx])
+        b.write_block(block2)
+
+        monkeypatch.setattr('time.time', lambda: 1000000030)
+        transfer_tx2 = Transaction.transfer(tx.to_inputs(), [([b.me], 2)],
+                                            asset_id=tx.id)
+        transfer_tx2 = transfer_tx2.sign([b.me_private])
+        block3 = b.create_block([transfer_tx2])
+        b.write_block(block3)
+
+        # Vote both block2 and block3 valid
+        vote = b.vote(block2.id, b.get_last_voted_block().id, True)
+        b.write_vote(vote)
+        vote = b.vote(block3.id, b.get_last_voted_block().id, True)
+        b.write_vote(vote)
+
+        with pytest.raises(CriticalDoubleSpend):
             b.get_spent(tx.id, 0)
 
     @pytest.mark.genesis
     def test_get_block_status_for_tx_with_double_inclusion(self, b, monkeypatch):
-        from bigchaindb.backend.exceptions import BigchainDBCritical
+        from bigchaindb.backend.exceptions import CriticalDoubleInclusion
         from bigchaindb.models import Transaction
 
         tx = Transaction.create([b.me], [([b.me], 1)])
@@ -148,7 +183,7 @@ class TestBigchainApi(object):
         vote = b.vote(block2.id, b.get_last_voted_block().id, True)
         b.write_vote(vote)
 
-        with pytest.raises(BigchainDBCritical):
+        with pytest.raises(CriticalDoubleInclusion):
             b.get_blocks_status_containing_tx(tx.id)
 
     @pytest.mark.genesis