Problem: Outputs API doesn't respond with correct unspent/spent outputs

Solution: Fix fastquery such that embedded document is queried properly

bigchaindb/common/transaction.py

@@ -274,6 +274,15 @@ class TransactionLink(object):
                 'output_index': self.output,
             }
 
+    def to_query(self):
+        if self.txid is None and self.output is None:
+            return None
+        else:
+            return [{'transaction_id': self.txid,
+                     'output_index': self.output},
+                    {'output_index': self.output,
+                     'transaction_id': self.txid}]
+
     def to_uri(self, path=''):
         if self.txid is None and self.output is None:
             return None

bigchaindb/fastquery.py

@@ -5,6 +5,7 @@
 from bigchaindb.utils import condition_details_has_owner
 from bigchaindb.backend import query
 from bigchaindb.common.transaction import TransactionLink
+from itertools import chain
 
 
 class FastQuery():
@@ -28,7 +29,7 @@ class FastQuery():
         Args:
             outputs: list of TransactionLink
         """
-        links = [o.to_dict() for o in outputs]
+        links = list(chain.from_iterable([o.to_query() for o in outputs]))
         txs = list(query.get_spending_transactions(self.connection, links))
         spends = {TransactionLink.from_dict(input_['fulfills'])
                   for tx in txs
@@ -41,7 +42,7 @@ class FastQuery():
         Args:
             outputs: list of TransactionLink
         """
-        links = [o.to_dict() for o in outputs]
+        links = list(chain.from_iterable([o.to_query() for o in outputs]))
         txs = list(query.get_spending_transactions(self.connection, links))
         spends = {TransactionLink.from_dict(input_['fulfills'])
                   for tx in txs

tests/tendermint/test_fastquery.py

@@ -73,3 +73,49 @@ def test_filter_unspent_outputs(b, user_pk, user_sk):
     assert set(sp for sp in spents) == {
         inputs[0].fulfills,
     }
+
+
+def test_outputs_query_key_order(b, user_pk, user_sk, user2_pk, user2_sk):
+    from bigchaindb import backend
+    from bigchaindb.backend import connect
+
+    tx1 = Transaction.create([user_pk],
+                             [([user_pk], 3), ([user_pk], 2), ([user_pk], 1)])\
+                     .sign([user_sk])
+    b.store_bulk_transactions([tx1])
+
+    inputs = tx1.to_inputs()
+    tx2 = Transaction.transfer([inputs[0]], [([user2_pk], 2)], tx1.id).sign([user_sk])
+
+    tx2_dict = tx2.to_dict()
+    fulfills = tx2_dict['inputs'][0]['fulfills']
+
+    tx2_dict['inputs'][0]['fulfills'] = {'transaction_id': fulfills['transaction_id'],
+                                         'output_index': fulfills['output_index']}
+
+    backend.query.store_transactions(b.connection, [tx2_dict])
+
+    outputs = b.get_outputs_filtered(user_pk, spent=False)
+    assert len(outputs) == 2
+
+    outputs = b.get_outputs_filtered(user2_pk, spent=False)
+    assert len(outputs) == 1
+
+    # clean the transaction, metdata and asset collection
+    conn = connect()
+    conn.run(conn.collection('transactions').delete_many({}))
+    conn.run(conn.collection('metadata').delete_many({}))
+    conn.run(conn.collection('assets').delete_many({}))
+
+    b.store_bulk_transactions([tx1])
+    tx2_dict = tx2.to_dict()
+
+    tx2_dict['inputs'][0]['fulfills'] = {'output_index': fulfills['output_index'],
+                                         'transaction_id': fulfills['transaction_id']}
+
+    backend.query.store_transactions(b.connection, [tx2_dict])
+    outputs = b.get_outputs_filtered(user_pk, spent=False)
+    assert len(outputs) == 2
+
+    outputs = b.get_outputs_filtered(user2_pk, spent=False)
+    assert len(outputs) == 1