From c572464be656f829a3cb935d2bc71dd680f7d645 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Wed, 1 Feb 2017 14:47:19 +0100
Subject: [PATCH 1/2] fix asset_id index in mongodb

---
 bigchaindb/backend/mongodb/schema.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/bigchaindb/backend/mongodb/schema.py b/bigchaindb/backend/mongodb/schema.py
index 2c526e7c..f6aac93d 100644
--- a/bigchaindb/backend/mongodb/schema.py
+++ b/bigchaindb/backend/mongodb/schema.py
@@ -60,8 +60,7 @@ def create_bigchain_secondary_index(conn, dbname):
 
     # secondary index for asset uuid, this field is unique
     conn.conn[dbname]['bigchain']\
-        .create_index('block.transactions.transaction.asset.id',
-                      name='asset_id')
+        .create_index('block.transactions.asset.id', name='asset_id')
 
 
 def create_backlog_secondary_index(conn, dbname):

From d3e394e7edf1facb05260b97833c2221b08f8491 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Fri, 3 Feb 2017 10:44:06 +0100
Subject: [PATCH 2/2] refactor get_txids_filtered query to be more efficient
 and add test to check that appropriate indexes are used

---
 bigchaindb/backend/mongodb/query.py   | 54 +++++++++++----------------
 tests/backend/mongodb/test_indexes.py | 23 ++++++++++++
 2 files changed, 45 insertions(+), 32 deletions(-)
 create mode 100644 tests/backend/mongodb/test_indexes.py

diff --git a/bigchaindb/backend/mongodb/query.py b/bigchaindb/backend/mongodb/query.py
index d7ee6afc..2bbfa08f 100644
--- a/bigchaindb/backend/mongodb/query.py
+++ b/bigchaindb/backend/mongodb/query.py
@@ -1,7 +1,6 @@
 """Query implementation for MongoDB"""
 
 from time import time
-from itertools import chain
 
 from pymongo import ReturnDocument
 from pymongo import errors
@@ -86,39 +85,30 @@ def get_blocks_status_from_transaction(conn, transaction_id):
 
 @register_query(MongoDBConnection)
 def get_txids_filtered(conn, asset_id, operation=None):
-    parts = []
+    match_create = {
+        'block.transactions.operation': 'CREATE',
+        'block.transactions.id': asset_id
+    }
+    match_transfer = {
+        'block.transactions.operation': 'TRANSFER',
+        'block.transactions.asset.id': asset_id
+    }
 
-    if operation in (Transaction.CREATE, None):
-        # get the txid of the create transaction for asset_id
-        cursor = conn.db['bigchain'].aggregate([
-            {'$match': {
-                'block.transactions.id': asset_id,
-                'block.transactions.operation': 'CREATE'
-            }},
-            {'$unwind': '$block.transactions'},
-            {'$match': {
-                'block.transactions.id': asset_id,
-                'block.transactions.operation': 'CREATE'
-            }},
-            {'$project': {'block.transactions.id': True}}
-        ])
-        parts.append(elem['block']['transactions']['id'] for elem in cursor)
+    if operation == Transaction.CREATE:
+        match = match_create
+    elif operation == Transaction.TRANSFER:
+        match = match_transfer
+    else:
+        match = {'$or': [match_create, match_transfer]}
 
-    if operation in (Transaction.TRANSFER, None):
-        # get txids of transfer transaction with asset_id
-        cursor = conn.db['bigchain'].aggregate([
-            {'$match': {
-                'block.transactions.asset.id': asset_id
-            }},
-            {'$unwind': '$block.transactions'},
-            {'$match': {
-                'block.transactions.asset.id': asset_id
-            }},
-            {'$project': {'block.transactions.id': True}}
-        ])
-        parts.append(elem['block']['transactions']['id'] for elem in cursor)
-
-    return chain(*parts)
+    pipeline = [
+        {'$match': match},
+        {'$unwind': '$block.transactions'},
+        {'$match': match},
+        {'$project': {'block.transactions.id': True}}
+    ]
+    cursor = conn.db['bigchain'].aggregate(pipeline)
+    return (elem['block']['transactions']['id'] for elem in cursor)
 
 
 @register_query(MongoDBConnection)
diff --git a/tests/backend/mongodb/test_indexes.py b/tests/backend/mongodb/test_indexes.py
new file mode 100644
index 00000000..ba6afae1
--- /dev/null
+++ b/tests/backend/mongodb/test_indexes.py
@@ -0,0 +1,23 @@
+import pytest
+from unittest.mock import MagicMock
+
+pytestmark = pytest.mark.bdb
+
+
+def test_asset_id_index():
+    from bigchaindb.backend.mongodb.query import get_txids_filtered
+    from bigchaindb.backend import connect
+
+    # Passes a mock in place of a connection to get the query params from the
+    # query function, then gets the explain plan from MongoDB to test that
+    # it's using certain indexes.
+
+    m = MagicMock()
+    get_txids_filtered(m, '')
+    pipeline = m.db['bigchain'].aggregate.call_args[0][0]
+    run = connect().db.command
+    res = run('aggregate', 'bigchain', pipeline=pipeline, explain=True)
+    stages = (res['stages'][0]['$cursor']['queryPlanner']['winningPlan']
+                 ['inputStage']['inputStages'])
+    indexes = [s['inputStage']['indexName'] for s in stages]
+    assert set(indexes) == {'asset_id', 'transaction_id'}