From 4f991227586dffe457c1fc04f4f7eba783bdd3a4 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Wed, 19 Apr 2017 15:47:58 +0200
Subject: [PATCH 01/26] fast unspents

---
 bigchaindb/backend/mongodb/query.py   | 31 ++++++++++-
 bigchaindb/backend/query.py           | 28 ++++++++++
 bigchaindb/common/transaction.py      |  3 +
 bigchaindb/core.py                    | 11 ++--
 bigchaindb/fastquery.py               | 56 +++++++++++++++++++
 tests/backend/mongodb/test_queries.py | 51 +++++++++++++++++
 tests/db/test_bigchain_api.py         | 12 ++--
 tests/test_fastquery.py               | 80 +++++++++++++++++++++++++++
 8 files changed, 261 insertions(+), 11 deletions(-)
 create mode 100644 bigchaindb/fastquery.py
 create mode 100644 tests/test_fastquery.py

diff --git a/bigchaindb/backend/mongodb/query.py b/bigchaindb/backend/mongodb/query.py
index 74b9c35a..d564e242 100644
--- a/bigchaindb/backend/mongodb/query.py
+++ b/bigchaindb/backend/mongodb/query.py
@@ -176,13 +176,33 @@ def get_spent(conn, transaction_id, output):
 
 
 @register_query(MongoDBConnection)
-def get_owned_ids(conn, owner):
+def get_spending_transactions(conn, inputs):
+    return conn.run(
+        conn.collection('bigchain').aggregate([
+            {'$match': {
+                'block.transactions.inputs.fulfills': {
+                    '$in': inputs,
+                },
+            }},
+            {'$unwind': '$block.transactions'},
+            {'$match': {
+                'block.transactions.inputs.fulfills': {
+                    '$in': inputs,
+                },
+            }},
+        ]))
+
+
+@register_query(MongoDBConnection)
+def get_owned_ids(conn, owner, unwrap=True):
     cursor = conn.run(
         conn.collection('bigchain').aggregate([
             {'$match': {'block.transactions.outputs.public_keys': owner}},
             {'$unwind': '$block.transactions'},
             {'$match': {'block.transactions.outputs.public_keys': owner}}
         ]))
+    if not unwrap:
+        return cursor
     # we need to access some nested fields before returning so lets use a
     # generator to avoid having to read all records on the cursor at this point
     return (elem['block']['transactions'] for elem in cursor)
@@ -196,6 +216,15 @@ def get_votes_by_block_id(conn, block_id):
               projection={'_id': False}))
 
 
+@register_query(MongoDBConnection)
+def get_votes_for_blocks_by_voter(conn, block_ids, node_pubkey):
+    return conn.run(
+        conn.collection('votes')
+        .find({'vote.voting_for_block': {'$in': block_ids},
+               'node_pubkey': node_pubkey},
+              projection={'_id': False}))
+
+
 @register_query(MongoDBConnection)
 def get_votes_by_block_id_and_voter(conn, block_id, node_pubkey):
     return conn.run(
diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 9aa653d7..5ae39557 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -140,6 +140,19 @@ def get_spent(connection, transaction_id, condition_id):
     raise NotImplementedError
 
 
+@singledispatch
+def get_spending_transactions(connection, inputs):
+    """Return transactions which spend given inputs
+
+    Args:
+        inputs (list): list of {txid, output}
+
+    Returns:
+        List of transactions that spend given inputs
+    """
+    raise NotImplementedError
+
+
 @singledispatch
 def get_owned_ids(connection, owner):
     """Retrieve a list of `txids` that can we used has inputs.
@@ -183,6 +196,21 @@ def get_votes_by_block_id_and_voter(connection, block_id, node_pubkey):
     raise NotImplementedError
 
 
+@singledispatch
+def get_votes_for_blocks_by_voter(connection, block_ids, pubkey):
+    """Return votes for many block_ids
+
+    Args:
+        block_ids (set): block_ids
+        pubkey (str): public key of voting node
+
+    Returns:
+        A cursor of votes matching given votes.
+    """
+
+    raise NotImplementedError
+
+
 @singledispatch
 def write_block(connection, block):
     """Write a block to the bigchain table.
diff --git a/bigchaindb/common/transaction.py b/bigchaindb/common/transaction.py
index e956812f..7d17172a 100644
--- a/bigchaindb/common/transaction.py
+++ b/bigchaindb/common/transaction.py
@@ -161,6 +161,9 @@ class TransactionLink(object):
         # TODO: If `other !== TransactionLink` return `False`
         return self.to_dict() == other.to_dict()
 
+    def __hash__(self):
+        return hash((self.txid, self.output))
+
     @classmethod
     def from_dict(cls, link):
         """Transforms a Python dictionary to a TransactionLink object.
diff --git a/bigchaindb/core.py b/bigchaindb/core.py
index 5d2e9c03..be7cdcbc 100644
--- a/bigchaindb/core.py
+++ b/bigchaindb/core.py
@@ -8,7 +8,7 @@ from bigchaindb.common.transaction import TransactionLink
 
 import bigchaindb
 
-from bigchaindb import backend, config_utils, utils
+from bigchaindb import backend, config_utils, utils, fastquery
 from bigchaindb.consensus import BaseConsensusRules
 from bigchaindb.models import Block, Transaction
 
@@ -433,14 +433,17 @@ class Bigchain(object):
         """
         return self.get_outputs_filtered(owner, include_spent=False)
 
+    @property
+    def fastquery(self):
+        return fastquery.FastQuery(self.connection, self.me)
+
     def get_outputs_filtered(self, owner, include_spent=True):
         """
         Get a list of output links filtered on some criteria
         """
-        outputs = self.get_outputs(owner)
+        outputs = self.fastquery.get_outputs_by_pubkey(owner)
         if not include_spent:
-            outputs = [o for o in outputs
-                       if not self.get_spent(o.txid, o.output)]
+            outputs = self.fastquery.filter_spent_outputs(outputs)
         return outputs
 
     def get_transactions_filtered(self, asset_id, operation=None):
diff --git a/bigchaindb/fastquery.py b/bigchaindb/fastquery.py
new file mode 100644
index 00000000..f2a8fb09
--- /dev/null
+++ b/bigchaindb/fastquery.py
@@ -0,0 +1,56 @@
+from bigchaindb.utils import output_has_owner
+from bigchaindb.backend import query
+from bigchaindb.common.transaction import TransactionLink
+
+
+class FastQuery:
+
+    """
+    Database queries that join on block results from a single node.
+
+    * Votes are not validated for security (security is replication concern)
+    * Votes come from only one node, and as such, fault tolerance is not provided
+      (elected Blockchain table not yet available)
+
+    In return, these queries offer good performance, as it is not neccesary to validate
+    each result separately.
+    """
+
+    def __init__(self, connection, me):
+        self.connection = connection
+        self.me = me
+
+    def filter_block_ids(self, block_ids, include_undecided=True):
+        votes = query.get_votes_for_blocks_by_voter(
+                    self.connection, block_ids, self.me)
+        votes = {v['vote']['voting_for_block']: v['vote']['is_block_valid'] for v in votes}
+        return [b for b in block_ids if votes.get(b, include_undecided)]
+
+    def filter_valid_blocks(self, blocks):
+        block_ids = list(set(b['id'] for b in blocks))
+        valid_block_ids = self.filter_block_ids(block_ids)
+        return [b for b in blocks if b['id'] in valid_block_ids]
+
+    def get_outputs_by_pubkey(self, pubkey):
+        cursor = query.get_owned_ids(self.connection, pubkey, unwrap=False)
+        wrapped_txs = self.filter_valid_blocks(list(cursor))
+        txs = [wrapped['block']['transactions'] for wrapped in wrapped_txs]
+        return [TransactionLink(tx['id'], i)
+                for tx in txs
+                for i, o in enumerate(tx['outputs'])
+                if output_has_owner(o, pubkey)]
+
+    def filter_spent_outputs(self, outputs):
+        """
+        Remove outputs that have been spent
+
+        Args:
+            outputs: list of TransactionLink
+        """
+        links = [o.to_dict() for o in outputs]
+        wrapped = self.filter_valid_blocks(
+                list(query.get_spending_transactions(self.connection, links)))
+        spends = {TransactionLink.from_dict(input_['fulfills'])
+                  for block in wrapped
+                  for input_ in block['block']['transactions']['inputs']}
+        return [ff for ff in outputs if ff not in spends]
diff --git a/tests/backend/mongodb/test_queries.py b/tests/backend/mongodb/test_queries.py
index bd7e75f1..c8a03011 100644
--- a/tests/backend/mongodb/test_queries.py
+++ b/tests/backend/mongodb/test_queries.py
@@ -417,3 +417,54 @@ def test_get_txids_filtered(signed_create_tx, signed_transfer_tx):
     # Test get by asset and TRANSFER
     txids = set(query.get_txids_filtered(conn, asset_id, Transaction.TRANSFER))
     assert txids == {signed_transfer_tx.id}
+
+
+def test_get_spending_transactions(user_pk):
+    from bigchaindb.backend import connect, query
+    from bigchaindb.models import Block, Transaction
+    conn = connect()
+
+    out = [([user_pk], 1)]
+    tx1 = Transaction.create([user_pk], out * 3)
+    inputs = tx1.to_inputs()
+    tx2 = Transaction.transfer([inputs[0]], out, tx1.id)
+    tx3 = Transaction.transfer([inputs[1]], out, tx1.id)
+    tx4 = Transaction.transfer([inputs[2]], out, tx1.id)
+    block = Block([tx1, tx2, tx3, tx4])
+    conn.db.bigchain.insert_one(block.to_dict())
+
+    links = [inputs[0].fulfills.to_dict(), inputs[2].fulfills.to_dict()]
+    # discard block noise
+    res = [(r['id'], r['block']['transactions'])
+           for r in list(query.get_spending_transactions(conn, links))]
+
+    # tx3 not a member because input 1 not asked for
+    assert res == [(block.id, tx2.to_dict()), (block.id, tx4.to_dict())]
+
+
+def test_get_votes_for_blocks_by_voter():
+    from bigchaindb.backend import connect, query
+
+    conn = connect()
+    votes = [
+        {
+            'node_pubkey': 'a',
+            'vote': {'voting_for_block': 'block1'},
+        },
+        {
+            'node_pubkey': 'b',
+            'vote': {'voting_for_block': 'block1'},
+        },
+        {
+            'node_pubkey': 'a',
+            'vote': {'voting_for_block': 'block2'},
+        },
+        {
+            'node_pubkey': 'a',
+            'vote': {'voting_for_block': 'block3'},
+        }
+    ]
+    for vote in votes:
+        conn.db.votes.insert_one(vote.copy())
+    res = query.get_votes_for_blocks_by_voter(conn, ['block1', 'block2'], 'a')
+    assert list(res) == [votes[0], votes[2]]
diff --git a/tests/db/test_bigchain_api.py b/tests/db/test_bigchain_api.py
index 3f05385c..589671e5 100644
--- a/tests/db/test_bigchain_api.py
+++ b/tests/db/test_bigchain_api.py
@@ -1119,11 +1119,11 @@ def test_get_owned_ids_calls_get_outputs_filtered():
 def test_get_outputs_filtered_only_unspent():
     from bigchaindb.common.transaction import TransactionLink
     from bigchaindb.core import Bigchain
-    with patch('bigchaindb.core.Bigchain.get_outputs') as get_outputs:
+    with patch('bigchaindb.fastquery.FastQuery.get_outputs_by_pubkey') as get_outputs:
         get_outputs.return_value = [TransactionLink('a', 1),
                                     TransactionLink('b', 2)]
-        with patch('bigchaindb.core.Bigchain.get_spent') as get_spent:
-            get_spent.side_effect = [True, False]
+        with patch('bigchaindb.fastquery.FastQuery.filter_spent_outputs') as filter_spent:
+            filter_spent.return_value = [TransactionLink('b', 2)]
             out = Bigchain().get_outputs_filtered('abc', include_spent=False)
     get_outputs.assert_called_once_with('abc')
     assert out == [TransactionLink('b', 2)]
@@ -1132,13 +1132,13 @@ def test_get_outputs_filtered_only_unspent():
 def test_get_outputs_filtered():
     from bigchaindb.common.transaction import TransactionLink
     from bigchaindb.core import Bigchain
-    with patch('bigchaindb.core.Bigchain.get_outputs') as get_outputs:
+    with patch('bigchaindb.fastquery.FastQuery.get_outputs_by_pubkey') as get_outputs:
         get_outputs.return_value = [TransactionLink('a', 1),
                                     TransactionLink('b', 2)]
-        with patch('bigchaindb.core.Bigchain.get_spent') as get_spent:
+        with patch('bigchaindb.fastquery.FastQuery.filter_spent_outputs') as filter_spent:
             out = Bigchain().get_outputs_filtered('abc')
     get_outputs.assert_called_once_with('abc')
-    get_spent.assert_not_called()
+    filter_spent.assert_not_called()
     assert out == get_outputs.return_value
 
 
diff --git a/tests/test_fastquery.py b/tests/test_fastquery.py
new file mode 100644
index 00000000..b730eee9
--- /dev/null
+++ b/tests/test_fastquery.py
@@ -0,0 +1,80 @@
+import pytest
+
+from bigchaindb.common.transaction import TransactionLink
+from bigchaindb.models import Block, Transaction
+
+pytestmark = pytest.mark.bdb
+
+
+@pytest.fixture
+def blockdata(b, user_pk, user2_pk):
+    txs = [Transaction.create([user_pk], [([user2_pk], 1)]),
+           Transaction.create([user2_pk], [([user_pk], 1)]),
+           Transaction.create([user_pk], [([user_pk], 1), ([user2_pk], 1)])]
+    blocks = []
+    for i in range(3):
+        block = Block([txs[i]])
+        b.write_block(block)
+        blocks.append(block.to_dict())
+        if i > 0:
+            b.write_vote(b.vote(block.id, '', i % 2 == 1))
+    return blocks, [b['id'] for b in blocks]
+
+
+def test_filter_block_ids_with_undecided(b, blockdata):
+    blocks, block_ids = blockdata
+    valid_ids = b.fastquery.filter_block_ids(block_ids)
+    assert set(valid_ids) == {blocks[0]['id'], blocks[1]['id']}
+
+
+def test_filter_block_ids_only_valid(b, blockdata):
+    blocks, block_ids = blockdata
+    valid_ids = b.fastquery.filter_block_ids(block_ids, include_undecided=False)
+    assert set(valid_ids) == {blocks[1]['id']}
+
+
+def test_filter_valid_blocks(b, blockdata):
+    blocks, _ = blockdata
+    assert b.fastquery.filter_valid_blocks(blocks) == [blocks[0], blocks[1]]
+
+
+def test_get_outputs_by_pubkey(b, user_pk, user2_pk, blockdata):
+    blocks, _ = blockdata
+    assert b.fastquery.get_outputs_by_pubkey(user_pk) == [
+            TransactionLink(blocks[1]['block']['transactions'][0]['id'], 0)
+    ]
+    assert b.fastquery.get_outputs_by_pubkey(user2_pk) == [
+            TransactionLink(blocks[0]['block']['transactions'][0]['id'], 0)
+    ]
+
+
+def test_filter_spent_outputs(b, user_pk):
+    out = [([user_pk], 1)]
+    tx1 = Transaction.create([user_pk], out * 3)
+    inputs = tx1.to_inputs()
+    tx2 = Transaction.transfer([inputs[0]], out, tx1.id)
+    tx3 = Transaction.transfer([inputs[1]], out, tx1.id)
+    tx4 = Transaction.transfer([inputs[2]], out, tx1.id)
+
+    for tx in [tx1, tx2]:
+        block = Block([tx])
+        b.write_block(block)
+        b.write_vote(b.vote(block.id, '', True))
+
+    # mark invalid
+    block = Block([tx3])
+    b.write_block(block)
+    b.write_vote(b.vote(block.id, '', False))
+
+    # undecided
+    block = Block([tx4])
+    b.write_block(block)
+
+    unspents = b.fastquery.filter_spent_outputs(
+             b.fastquery.get_outputs_by_pubkey(user_pk))
+
+    assert set(unspents) == {
+        inputs[1].fulfills,
+        tx2.to_inputs()[0].fulfills,
+        tx4.to_inputs()[0].fulfills
+    }

From 5b6fa13d798a6bed27fc662f1db6b2a11e7ef885 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Thu, 20 Apr 2017 16:58:29 +0200
Subject: [PATCH 02/26] fast unspent queries for RethinkDB

---
 bigchaindb/backend/rethinkdb/query.py | 38 +++++++++++++++++++++++----
 bigchaindb/fastquery.py               |  4 +--
 tests/test_fastquery.py               | 13 ++++++---
 3 files changed, 44 insertions(+), 11 deletions(-)

diff --git a/bigchaindb/backend/rethinkdb/query.py b/bigchaindb/backend/rethinkdb/query.py
index 6011cc8c..6a2c644e 100644
--- a/bigchaindb/backend/rethinkdb/query.py
+++ b/bigchaindb/backend/rethinkdb/query.py
@@ -120,14 +120,16 @@ def get_spent(connection, transaction_id, output):
 
 
 @register_query(RethinkDBConnection)
-def get_owned_ids(connection, owner):
-    return connection.run(
-            r.table('bigchain', read_mode=READ_MODE)
+def get_owned_ids(connection, owner, unwrap=True):
+    query = (r.table('bigchain', read_mode=READ_MODE)
              .get_all(owner, index='outputs')
              .distinct()
-             .concat_map(lambda doc: doc['block']['transactions'])
-             .filter(lambda tx: tx['outputs'].contains(
+             .concat_map(unroll_block_transactions)
+             .filter(lambda doc: doc['block']['transactions']['outputs'].contains(
                 lambda c: c['public_keys'].contains(owner))))
+    if unwrap:
+        query = query.map(lambda doc: doc['block']['transactions'])
+    return connection.run(query)
 
 
 @register_query(RethinkDBConnection)
@@ -253,3 +255,29 @@ def get_unvoted_blocks(connection, node_pubkey):
     #        database level. Solving issue #444 can help untangling the situation
     unvoted_blocks = filter(lambda block: not utils.is_genesis_block(block), unvoted)
     return unvoted_blocks
+
+
+@register_query(RethinkDBConnection)
+def get_votes_for_blocks_by_voter(connection, block_ids, node_pubkey):
+    return connection.run(
+        r.table('votes')
+        .filter(lambda row: r.expr(block_ids).contains(row['vote']['voting_for_block']))
+        .filter(lambda row: row['node_pubkey'] == node_pubkey))
+
+
+def unroll_block_transactions(block):
+    """ Simulate unrolling a transaction into block in MongoDB """
+    return block['block']['transactions'].map(
+             lambda tx: block.merge({'block': {'transactions': tx}}))
+
+
+@register_query(RethinkDBConnection)
+def get_spending_transactions(connection, links):
+    query = (
+        r.table('bigchain')
+        .get_all(*[(l['txid'], l['output']) for l in links], index='inputs')
+        .concat_map(unroll_block_transactions)
+        .filter(lambda doc: r.expr(links).set_intersection(
+            doc['block']['transactions']['inputs'].map(lambda i: i['fulfills'])))
+    )
+    return connection.run(query)
diff --git a/bigchaindb/fastquery.py b/bigchaindb/fastquery.py
index f2a8fb09..7b73ab64 100644
--- a/bigchaindb/fastquery.py
+++ b/bigchaindb/fastquery.py
@@ -48,8 +48,8 @@ class FastQuery:
             outputs: list of TransactionLink
         """
         links = [o.to_dict() for o in outputs]
-        wrapped = self.filter_valid_blocks(
-                list(query.get_spending_transactions(self.connection, links)))
+        spending_txs = query.get_spending_transactions(self.connection, links)
+        wrapped = self.filter_valid_blocks(list(spending_txs))
         spends = {TransactionLink.from_dict(input_['fulfills'])
                   for block in wrapped
                   for input_ in block['block']['transactions']['inputs']}
diff --git a/tests/test_fastquery.py b/tests/test_fastquery.py
index b730eee9..8621751a 100644
--- a/tests/test_fastquery.py
+++ b/tests/test_fastquery.py
@@ -51,27 +51,32 @@ def test_get_outputs_by_pubkey(b, user_pk, user2_pk, blockdata):
 def test_filter_spent_outputs(b, user_pk):
     out = [([user_pk], 1)]
     tx1 = Transaction.create([user_pk], out * 3)
+
+    # There are 3 inputs
     inputs = tx1.to_inputs()
+
+    # Each spent individually
     tx2 = Transaction.transfer([inputs[0]], out, tx1.id)
     tx3 = Transaction.transfer([inputs[1]], out, tx1.id)
     tx4 = Transaction.transfer([inputs[2]], out, tx1.id)
 
+    # The CREATE and first TRANSFER are valid. tx2 produces a new unspent.
     for tx in [tx1, tx2]:
         block = Block([tx])
         b.write_block(block)
         b.write_vote(b.vote(block.id, '', True))
 
-    # mark invalid
+    # The second TRANSFER is invalid. inputs[1] remains unspent.
     block = Block([tx3])
     b.write_block(block)
     b.write_vote(b.vote(block.id, '', False))
 
-    # undecided
+    # The third TRANSFER is undecided. It procuces a new unspent.
     block = Block([tx4])
     b.write_block(block)
 
-    unspents = b.fastquery.filter_spent_outputs(
-             b.fastquery.get_outputs_by_pubkey(user_pk))
+    outputs = b.fastquery.get_outputs_by_pubkey(user_pk)
+    unspents = b.fastquery.filter_spent_outputs(outputs)
 
     assert set(unspents) == {
         inputs[1].fulfills,

From 29247a9994758e2d511a2f686abb3cc4b8f94e54 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Thu, 20 Apr 2017 16:58:40 +0200
Subject: [PATCH 03/26] test clarification

---
 tests/test_fastquery.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/test_fastquery.py b/tests/test_fastquery.py
index 8621751a..200bd7f9 100644
--- a/tests/test_fastquery.py
+++ b/tests/test_fastquery.py
@@ -16,8 +16,8 @@ def blockdata(b, user_pk, user2_pk):
         block = Block([txs[i]])
         b.write_block(block)
         blocks.append(block.to_dict())
-        if i > 0:
-            b.write_vote(b.vote(block.id, '', i % 2 == 1))
+    b.write_vote(b.vote(blocks[1]['id'], '', True))
+    b.write_vote(b.vote(blocks[2]['id'], '', False))
     return blocks, [b['id'] for b in blocks]
 
 

From 5d767c1162effa3f657f5d6c5c5a3594bdc11662 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Fri, 21 Apr 2017 12:23:53 +0200
Subject: [PATCH 04/26] light refactoring to remove some redundancies and fix
 test coverage

---
 bigchaindb/backend/mongodb/query.py   | 11 +++---
 bigchaindb/backend/rethinkdb/query.py | 19 +++++------
 bigchaindb/core.py                    | 48 +--------------------------
 bigchaindb/fastquery.py               | 32 ++++++++++--------
 tests/backend/mongodb/test_queries.py |  9 +++--
 tests/backend/test_generics.py        |  2 ++
 tests/test_fastquery.py               |  3 +-
 7 files changed, 41 insertions(+), 83 deletions(-)

diff --git a/bigchaindb/backend/mongodb/query.py b/bigchaindb/backend/mongodb/query.py
index d564e242..0eab8c6b 100644
--- a/bigchaindb/backend/mongodb/query.py
+++ b/bigchaindb/backend/mongodb/query.py
@@ -177,7 +177,7 @@ def get_spent(conn, transaction_id, output):
 
 @register_query(MongoDBConnection)
 def get_spending_transactions(conn, inputs):
-    return conn.run(
+    cursor = conn.run(
         conn.collection('bigchain').aggregate([
             {'$match': {
                 'block.transactions.inputs.fulfills': {
@@ -191,21 +191,18 @@ def get_spending_transactions(conn, inputs):
                 },
             }},
         ]))
+    return ((b['id'], b['block']['transactions']) for b in cursor)
 
 
 @register_query(MongoDBConnection)
-def get_owned_ids(conn, owner, unwrap=True):
+def get_owned_ids(conn, owner):
     cursor = conn.run(
         conn.collection('bigchain').aggregate([
             {'$match': {'block.transactions.outputs.public_keys': owner}},
             {'$unwind': '$block.transactions'},
             {'$match': {'block.transactions.outputs.public_keys': owner}}
         ]))
-    if not unwrap:
-        return cursor
-    # we need to access some nested fields before returning so lets use a
-    # generator to avoid having to read all records on the cursor at this point
-    return (elem['block']['transactions'] for elem in cursor)
+    return ((b['id'], b['block']['transactions']) for b in cursor)
 
 
 @register_query(MongoDBConnection)
diff --git a/bigchaindb/backend/rethinkdb/query.py b/bigchaindb/backend/rethinkdb/query.py
index 6a2c644e..fca65bdf 100644
--- a/bigchaindb/backend/rethinkdb/query.py
+++ b/bigchaindb/backend/rethinkdb/query.py
@@ -120,16 +120,15 @@ def get_spent(connection, transaction_id, output):
 
 
 @register_query(RethinkDBConnection)
-def get_owned_ids(connection, owner, unwrap=True):
+def get_owned_ids(connection, owner):
     query = (r.table('bigchain', read_mode=READ_MODE)
              .get_all(owner, index='outputs')
              .distinct()
              .concat_map(unroll_block_transactions)
-             .filter(lambda doc: doc['block']['transactions']['outputs'].contains(
+             .filter(lambda doc: doc['tx']['outputs'].contains(
                 lambda c: c['public_keys'].contains(owner))))
-    if unwrap:
-        query = query.map(lambda doc: doc['block']['transactions'])
-    return connection.run(query)
+    cursor = connection.run(query)
+    return ((b['id'], b['tx']) for b in cursor)
 
 
 @register_query(RethinkDBConnection)
@@ -266,9 +265,8 @@ def get_votes_for_blocks_by_voter(connection, block_ids, node_pubkey):
 
 
 def unroll_block_transactions(block):
-    """ Simulate unrolling a transaction into block in MongoDB """
-    return block['block']['transactions'].map(
-             lambda tx: block.merge({'block': {'transactions': tx}}))
+    """ Unroll block transactions """
+    return block['block']['transactions'].map(lambda tx: block.merge({'tx': tx}))
 
 
 @register_query(RethinkDBConnection)
@@ -278,6 +276,7 @@ def get_spending_transactions(connection, links):
         .get_all(*[(l['txid'], l['output']) for l in links], index='inputs')
         .concat_map(unroll_block_transactions)
         .filter(lambda doc: r.expr(links).set_intersection(
-            doc['block']['transactions']['inputs'].map(lambda i: i['fulfills'])))
+            doc['tx']['inputs'].map(lambda i: i['fulfills'])))
     )
-    return connection.run(query)
+    cursor = connection.run(query)
+    return ((b['id'], b['tx']) for b in cursor)
diff --git a/bigchaindb/core.py b/bigchaindb/core.py
index be7cdcbc..63cab1d2 100644
--- a/bigchaindb/core.py
+++ b/bigchaindb/core.py
@@ -4,11 +4,10 @@ from time import time
 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
 
 import bigchaindb
 
-from bigchaindb import backend, config_utils, utils, fastquery
+from bigchaindb import backend, config_utils, fastquery
 from bigchaindb.consensus import BaseConsensusRules
 from bigchaindb.models import Block, Transaction
 
@@ -376,51 +375,6 @@ class Bigchain(object):
         # Either no transaction was returned spending the `(txid, output)` as
         # input or the returned transactions are not valid.
 
-    def get_outputs(self, owner):
-        """Retrieve a list of links to transaction outputs for a given public
-           key.
-
-        Args:
-            owner (str): base58 encoded public key.
-
-        Returns:
-            :obj:`list` of TransactionLink: list of ``txid`` s and ``output`` s
-            pointing to another transaction's condition
-        """
-        # get all transactions in which owner is in the `owners_after` list
-        response = backend.query.get_owned_ids(self.connection, owner)
-        return [
-            TransactionLink(tx['id'], index)
-            for tx in response
-            if not self.is_tx_strictly_in_invalid_block(tx['id'])
-            for index, output in enumerate(tx['outputs'])
-            if utils.output_has_owner(output, owner)
-        ]
-
-    def is_tx_strictly_in_invalid_block(self, txid):
-        """
-        Checks whether the transaction with the given ``txid``
-        *strictly* belongs to an invalid block.
-
-        Args:
-            txid (str): Transaction id.
-
-        Returns:
-            bool: ``True`` if the transaction *strictly* belongs to a
-            block that is invalid. ``False`` otherwise.
-
-        Note:
-            Since a transaction may be in multiple blocks, with
-            different statuses, the term "strictly" is used to
-            emphasize that if a transaction is said to be in an invalid
-            block, it means that it is not in any other block that is
-            either valid or undecided.
-
-        """
-        validity = self.get_blocks_status_containing_tx(txid)
-        return (Bigchain.BLOCK_VALID not in validity.values() and
-                Bigchain.BLOCK_UNDECIDED not in validity.values())
-
     def get_owned_ids(self, owner):
         """Retrieve a list of ``txid`` s that can be used as inputs.
 
diff --git a/bigchaindb/fastquery.py b/bigchaindb/fastquery.py
index 7b73ab64..a7147722 100644
--- a/bigchaindb/fastquery.py
+++ b/bigchaindb/fastquery.py
@@ -9,8 +9,7 @@ class FastQuery:
     Database queries that join on block results from a single node.
 
     * Votes are not validated for security (security is replication concern)
-    * Votes come from only one node, and as such, fault tolerance is not provided
-      (elected Blockchain table not yet available)
+    * Votes come from only one node, and as such, fault tolerance is reduced
 
     In return, these queries offer good performance, as it is not neccesary to validate
     each result separately.
@@ -21,20 +20,27 @@ class FastQuery:
         self.me = me
 
     def filter_block_ids(self, block_ids, include_undecided=True):
+        """
+        Given block ids, filter the invalid blocks
+        """
+        block_ids = list(set(block_ids))
         votes = query.get_votes_for_blocks_by_voter(
                     self.connection, block_ids, self.me)
         votes = {v['vote']['voting_for_block']: v['vote']['is_block_valid'] for v in votes}
         return [b for b in block_ids if votes.get(b, include_undecided)]
 
-    def filter_valid_blocks(self, blocks):
-        block_ids = list(set(b['id'] for b in blocks))
-        valid_block_ids = self.filter_block_ids(block_ids)
-        return [b for b in blocks if b['id'] in valid_block_ids]
+    def filter_valid_blocks(self, blocks, key=lambda b: b[0]):
+        """
+        Given things with block ids, remove the invalid ones.
+        """
+        blocks = list(blocks)
+        valid_block_ids = set(self.filter_block_ids(key(b) for b in blocks))
+        return [b for b in blocks if key(b) in valid_block_ids]
 
     def get_outputs_by_pubkey(self, pubkey):
-        cursor = query.get_owned_ids(self.connection, pubkey, unwrap=False)
-        wrapped_txs = self.filter_valid_blocks(list(cursor))
-        txs = [wrapped['block']['transactions'] for wrapped in wrapped_txs]
+        """ Get outputs for a public key """
+        res = list(query.get_owned_ids(self.connection, pubkey))
+        txs = [tx for _, tx in self.filter_valid_blocks(res)]
         return [TransactionLink(tx['id'], i)
                 for tx in txs
                 for i, o in enumerate(tx['outputs'])
@@ -48,9 +54,9 @@ class FastQuery:
             outputs: list of TransactionLink
         """
         links = [o.to_dict() for o in outputs]
-        spending_txs = query.get_spending_transactions(self.connection, links)
-        wrapped = self.filter_valid_blocks(list(spending_txs))
+        res = query.get_spending_transactions(self.connection, links)
+        txs = [tx for _, tx in self.filter_valid_blocks(res)]
         spends = {TransactionLink.from_dict(input_['fulfills'])
-                  for block in wrapped
-                  for input_ in block['block']['transactions']['inputs']}
+                  for tx in txs
+                  for input_ in tx['inputs']}
         return [ff for ff in outputs if ff not in spends]
diff --git a/tests/backend/mongodb/test_queries.py b/tests/backend/mongodb/test_queries.py
index c8a03011..426ac12d 100644
--- a/tests/backend/mongodb/test_queries.py
+++ b/tests/backend/mongodb/test_queries.py
@@ -205,10 +205,10 @@ def test_get_owned_ids(signed_create_tx, user_pk):
     block = Block(transactions=[signed_create_tx])
     conn.db.bigchain.insert_one(block.to_dict())
 
-    owned_ids = list(query.get_owned_ids(conn, user_pk))
+    [(block_id, tx)] = list(query.get_owned_ids(conn, user_pk))
 
-    assert len(owned_ids) == 1
-    assert owned_ids[0] == signed_create_tx.to_dict()
+    assert block_id == block.id
+    assert tx == signed_create_tx.to_dict()
 
 
 def test_get_votes_by_block_id(signed_create_tx, structurally_valid_vote):
@@ -435,8 +435,7 @@ def test_get_spending_transactions(user_pk):
 
     links = [inputs[0].fulfills.to_dict(), inputs[2].fulfills.to_dict()]
     # discard block noise
-    res = [(r['id'], r['block']['transactions'])
-           for r in list(query.get_spending_transactions(conn, links))]
+    res = list(query.get_spending_transactions(conn, links))
 
     # tx3 not a member because input 1 not asked for
     assert res == [(block.id, tx2.to_dict()), (block.id, tx4.to_dict())]
diff --git a/tests/backend/test_generics.py b/tests/backend/test_generics.py
index 57a644ee..581a0b31 100644
--- a/tests/backend/test_generics.py
+++ b/tests/backend/test_generics.py
@@ -36,6 +36,8 @@ def test_schema(schema_func_name, args_qty):
     ('get_votes_by_block_id_and_voter', 2),
     ('update_transaction', 2),
     ('get_transaction_from_block', 2),
+    ('get_votes_for_blocks_by_voter', 2),
+    ('get_spending_transactions', 1),
 ))
 def test_query(query_func_name, args_qty):
     from bigchaindb.backend import query
diff --git a/tests/test_fastquery.py b/tests/test_fastquery.py
index 200bd7f9..c54ef10e 100644
--- a/tests/test_fastquery.py
+++ b/tests/test_fastquery.py
@@ -35,7 +35,8 @@ def test_filter_block_ids_only_valid(b, blockdata):
 
 def test_filter_valid_blocks(b, blockdata):
     blocks, _ = blockdata
-    assert b.fastquery.filter_valid_blocks(blocks) == [blocks[0], blocks[1]]
+    assert (b.fastquery.filter_valid_blocks(blocks, key=lambda b: b['id'])
+            == [blocks[0], blocks[1]])
 
 
 def test_get_outputs_by_pubkey(b, user_pk, user2_pk, blockdata):

From 2200a7bda417e4d5ef4fd1f3297e7231249dbb85 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Mon, 24 Apr 2017 12:21:00 +0200
Subject: [PATCH 05/26] cleanup

---
 bigchaindb/backend/query.py           | 1 -
 bigchaindb/backend/rethinkdb/query.py | 9 +++++----
 tests/backend/mongodb/test_queries.py | 1 -
 3 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 5ae39557..0f746132 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -207,7 +207,6 @@ def get_votes_for_blocks_by_voter(connection, block_ids, pubkey):
     Returns:
         A cursor of votes matching given votes.
     """
-
     raise NotImplementedError
 
 
diff --git a/bigchaindb/backend/rethinkdb/query.py b/bigchaindb/backend/rethinkdb/query.py
index fca65bdf..18116fc1 100644
--- a/bigchaindb/backend/rethinkdb/query.py
+++ b/bigchaindb/backend/rethinkdb/query.py
@@ -124,7 +124,7 @@ def get_owned_ids(connection, owner):
     query = (r.table('bigchain', read_mode=READ_MODE)
              .get_all(owner, index='outputs')
              .distinct()
-             .concat_map(unroll_block_transactions)
+             .concat_map(unwind_block_transactions)
              .filter(lambda doc: doc['tx']['outputs'].contains(
                 lambda c: c['public_keys'].contains(owner))))
     cursor = connection.run(query)
@@ -264,8 +264,8 @@ def get_votes_for_blocks_by_voter(connection, block_ids, node_pubkey):
         .filter(lambda row: row['node_pubkey'] == node_pubkey))
 
 
-def unroll_block_transactions(block):
-    """ Unroll block transactions """
+def unwind_block_transactions(block):
+    """ Yield a block for each transaction in given block """
     return block['block']['transactions'].map(lambda tx: block.merge({'tx': tx}))
 
 
@@ -274,7 +274,8 @@ def get_spending_transactions(connection, links):
     query = (
         r.table('bigchain')
         .get_all(*[(l['txid'], l['output']) for l in links], index='inputs')
-        .concat_map(unroll_block_transactions)
+        .concat_map(unwind_block_transactions)
+        # filter transactions spending output
         .filter(lambda doc: r.expr(links).set_intersection(
             doc['tx']['inputs'].map(lambda i: i['fulfills'])))
     )
diff --git a/tests/backend/mongodb/test_queries.py b/tests/backend/mongodb/test_queries.py
index 426ac12d..0c295b9b 100644
--- a/tests/backend/mongodb/test_queries.py
+++ b/tests/backend/mongodb/test_queries.py
@@ -434,7 +434,6 @@ def test_get_spending_transactions(user_pk):
     conn.db.bigchain.insert_one(block.to_dict())
 
     links = [inputs[0].fulfills.to_dict(), inputs[2].fulfills.to_dict()]
-    # discard block noise
     res = list(query.get_spending_transactions(conn, links))
 
     # tx3 not a member because input 1 not asked for

From 01ba01083d26ba2c1d22eeedd4089a718f9589a9 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Tue, 25 Apr 2017 13:12:32 +0200
Subject: [PATCH 06/26] update comments

---
 bigchaindb/backend/query.py |  9 +++++----
 bigchaindb/fastquery.py     | 17 ++++++++++-------
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 0f746132..6f76249b 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -148,7 +148,8 @@ def get_spending_transactions(connection, inputs):
         inputs (list): list of {txid, output}
 
     Returns:
-        List of transactions that spend given inputs
+        Iterator of (block_ids, transaction) for transactions that
+        spend given inputs.
     """
     raise NotImplementedError
 
@@ -161,9 +162,9 @@ def get_owned_ids(connection, owner):
         owner (str): base58 encoded public key.
 
     Returns:
-        A cursor for the matching transactions.
+        Iterator of (block_id, transaction) for transactions
+        that list given owner in conditions.
     """
-
     raise NotImplementedError
 
 
@@ -205,7 +206,7 @@ def get_votes_for_blocks_by_voter(connection, block_ids, pubkey):
         pubkey (str): public key of voting node
 
     Returns:
-        A cursor of votes matching given votes.
+        A cursor of votes matching given block_ids and public key
     """
     raise NotImplementedError
 
diff --git a/bigchaindb/fastquery.py b/bigchaindb/fastquery.py
index a7147722..deffabe1 100644
--- a/bigchaindb/fastquery.py
+++ b/bigchaindb/fastquery.py
@@ -4,24 +4,27 @@ from bigchaindb.common.transaction import TransactionLink
 
 
 class FastQuery:
-
     """
     Database queries that join on block results from a single node.
 
-    * Votes are not validated for security (security is replication concern)
-    * Votes come from only one node, and as such, fault tolerance is reduced
+    * Votes are not validated for security (security is a replication concern)
+    * Votes come from only one node, and as such, non-byzantine fault tolerance
+      is reduced.
 
-    In return, these queries offer good performance, as it is not neccesary to validate
-    each result separately.
+    Previously, to consider the status of a block, all votes for that block
+    were retrieved and the election results were counted. This meant that a
+    faulty node may still have been able to obtain a correct election result.
+    However, from the point of view of a client, it is still neccesary to
+    query multiple nodes to insure against getting an incorrect response from
+    a byzantine node.
     """
-
     def __init__(self, connection, me):
         self.connection = connection
         self.me = me
 
     def filter_block_ids(self, block_ids, include_undecided=True):
         """
-        Given block ids, filter the invalid blocks
+        Given block ids, filter the invalid blocks.
         """
         block_ids = list(set(block_ids))
         votes = query.get_votes_for_blocks_by_voter(

From b4f14b26ce264e7c24053b6e9be4cbea21ade054 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Mon, 8 May 2017 14:25:39 +0200
Subject: [PATCH 07/26] address nomenclature issues

---
 bigchaindb/core.py            |  2 +-
 bigchaindb/fastquery.py       | 39 ++++++++++++++++++++---------------
 tests/db/test_bigchain_api.py |  4 ++--
 tests/test_fastquery.py       | 20 +++++++++---------
 4 files changed, 35 insertions(+), 30 deletions(-)

diff --git a/bigchaindb/core.py b/bigchaindb/core.py
index 63cab1d2..91666224 100644
--- a/bigchaindb/core.py
+++ b/bigchaindb/core.py
@@ -395,7 +395,7 @@ class Bigchain(object):
         """
         Get a list of output links filtered on some criteria
         """
-        outputs = self.fastquery.get_outputs_by_pubkey(owner)
+        outputs = self.fastquery.get_outputs_by_public_key(owner)
         if not include_spent:
             outputs = self.fastquery.filter_spent_outputs(outputs)
         return outputs
diff --git a/bigchaindb/fastquery.py b/bigchaindb/fastquery.py
index deffabe1..d19294ce 100644
--- a/bigchaindb/fastquery.py
+++ b/bigchaindb/fastquery.py
@@ -22,32 +22,37 @@ class FastQuery:
         self.connection = connection
         self.me = me
 
-    def filter_block_ids(self, block_ids, include_undecided=True):
+    def filter_valid_block_ids(self, block_ids, include_undecided=False):
         """
-        Given block ids, filter the invalid blocks.
+        Given block ids, return only the ones that are valid.
         """
         block_ids = list(set(block_ids))
         votes = query.get_votes_for_blocks_by_voter(
                     self.connection, block_ids, self.me)
-        votes = {v['vote']['voting_for_block']: v['vote']['is_block_valid'] for v in votes}
-        return [b for b in block_ids if votes.get(b, include_undecided)]
+        votes = {vote['vote']['voting_for_block']: vote['vote']['is_block_valid']
+                 for vote in votes}
+        return [block_id for block_id in block_ids
+                if votes.get(block_id, include_undecided)]
 
-    def filter_valid_blocks(self, blocks, key=lambda b: b[0]):
+    def filter_valid_items(self, items, block_id_key=lambda b: b[0]):
         """
-        Given things with block ids, remove the invalid ones.
+        Given items with block ids, return only the ones that are valid or undecided.
         """
-        blocks = list(blocks)
-        valid_block_ids = set(self.filter_block_ids(key(b) for b in blocks))
-        return [b for b in blocks if key(b) in valid_block_ids]
+        items = list(items)
+        block_ids = map(block_id_key, items)
+        valid_block_ids = set(self.filter_valid_block_ids(block_ids, True))
+        return [b for b in items if block_id_key(b) in valid_block_ids]
 
-    def get_outputs_by_pubkey(self, pubkey):
-        """ Get outputs for a public key """
-        res = list(query.get_owned_ids(self.connection, pubkey))
-        txs = [tx for _, tx in self.filter_valid_blocks(res)]
-        return [TransactionLink(tx['id'], i)
+    def get_outputs_by_public_key(self, public_key):
+        """
+        Get outputs for a public key
+        """
+        res = list(query.get_owned_ids(self.connection, public_key))
+        txs = [tx for _, tx in self.filter_valid_items(res)]
+        return [TransactionLink(tx['id'], index)
                 for tx in txs
-                for i, o in enumerate(tx['outputs'])
-                if output_has_owner(o, pubkey)]
+                for index, output in enumerate(tx['outputs'])
+                if output_has_owner(output, public_key)]
 
     def filter_spent_outputs(self, outputs):
         """
@@ -58,7 +63,7 @@ class FastQuery:
         """
         links = [o.to_dict() for o in outputs]
         res = query.get_spending_transactions(self.connection, links)
-        txs = [tx for _, tx in self.filter_valid_blocks(res)]
+        txs = [tx for _, tx in self.filter_valid_items(res)]
         spends = {TransactionLink.from_dict(input_['fulfills'])
                   for tx in txs
                   for input_ in tx['inputs']}
diff --git a/tests/db/test_bigchain_api.py b/tests/db/test_bigchain_api.py
index 589671e5..8d17a9e7 100644
--- a/tests/db/test_bigchain_api.py
+++ b/tests/db/test_bigchain_api.py
@@ -1119,7 +1119,7 @@ def test_get_owned_ids_calls_get_outputs_filtered():
 def test_get_outputs_filtered_only_unspent():
     from bigchaindb.common.transaction import TransactionLink
     from bigchaindb.core import Bigchain
-    with patch('bigchaindb.fastquery.FastQuery.get_outputs_by_pubkey') as get_outputs:
+    with patch('bigchaindb.fastquery.FastQuery.get_outputs_by_public_key') as get_outputs:
         get_outputs.return_value = [TransactionLink('a', 1),
                                     TransactionLink('b', 2)]
         with patch('bigchaindb.fastquery.FastQuery.filter_spent_outputs') as filter_spent:
@@ -1132,7 +1132,7 @@ def test_get_outputs_filtered_only_unspent():
 def test_get_outputs_filtered():
     from bigchaindb.common.transaction import TransactionLink
     from bigchaindb.core import Bigchain
-    with patch('bigchaindb.fastquery.FastQuery.get_outputs_by_pubkey') as get_outputs:
+    with patch('bigchaindb.fastquery.FastQuery.get_outputs_by_public_key') as get_outputs:
         get_outputs.return_value = [TransactionLink('a', 1),
                                     TransactionLink('b', 2)]
         with patch('bigchaindb.fastquery.FastQuery.filter_spent_outputs') as filter_spent:
diff --git a/tests/test_fastquery.py b/tests/test_fastquery.py
index c54ef10e..8fb3378c 100644
--- a/tests/test_fastquery.py
+++ b/tests/test_fastquery.py
@@ -21,30 +21,30 @@ def blockdata(b, user_pk, user2_pk):
     return blocks, [b['id'] for b in blocks]
 
 
-def test_filter_block_ids_with_undecided(b, blockdata):
+def test_filter_valid_block_ids_with_undecided(b, blockdata):
     blocks, block_ids = blockdata
-    valid_ids = b.fastquery.filter_block_ids(block_ids)
+    valid_ids = b.fastquery.filter_valid_block_ids(block_ids, include_undecided=True)
     assert set(valid_ids) == {blocks[0]['id'], blocks[1]['id']}
 
 
-def test_filter_block_ids_only_valid(b, blockdata):
+def test_filter_valid_block_ids_only_valid(b, blockdata):
     blocks, block_ids = blockdata
-    valid_ids = b.fastquery.filter_block_ids(block_ids, include_undecided=False)
+    valid_ids = b.fastquery.filter_valid_block_ids(block_ids)
     assert set(valid_ids) == {blocks[1]['id']}
 
 
-def test_filter_valid_blocks(b, blockdata):
+def test_filter_valid_items(b, blockdata):
     blocks, _ = blockdata
-    assert (b.fastquery.filter_valid_blocks(blocks, key=lambda b: b['id'])
+    assert (b.fastquery.filter_valid_items(blocks, block_id_key=lambda b: b['id'])
             == [blocks[0], blocks[1]])
 
 
-def test_get_outputs_by_pubkey(b, user_pk, user2_pk, blockdata):
+def test_get_outputs_by_public_key(b, user_pk, user2_pk, blockdata):
     blocks, _ = blockdata
-    assert b.fastquery.get_outputs_by_pubkey(user_pk) == [
+    assert b.fastquery.get_outputs_by_public_key(user_pk) == [
             TransactionLink(blocks[1]['block']['transactions'][0]['id'], 0)
     ]
-    assert b.fastquery.get_outputs_by_pubkey(user2_pk) == [
+    assert b.fastquery.get_outputs_by_public_key(user2_pk) == [
             TransactionLink(blocks[0]['block']['transactions'][0]['id'], 0)
     ]
 
@@ -76,7 +76,7 @@ def test_filter_spent_outputs(b, user_pk):
     block = Block([tx4])
     b.write_block(block)
 
-    outputs = b.fastquery.get_outputs_by_pubkey(user_pk)
+    outputs = b.fastquery.get_outputs_by_public_key(user_pk)
     unspents = b.fastquery.filter_spent_outputs(outputs)
 
     assert set(unspents) == {

From 92392b51a7a6e1eda3263d17d5ca3ffc2bf46f2c Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Wed, 10 May 2017 16:43:52 +0200
Subject: [PATCH 08/26] Initial implementation to decouple assets from
 transactions.

Most changes done to how we write and read blocks to the database.
Created schema, indexes and queries for mongodb.
Fixed tests.
---
 bigchaindb/backend/mongodb/query.py   | 38 +++++++++++++++---
 bigchaindb/backend/mongodb/schema.py  | 13 ++++++-
 bigchaindb/backend/query.py           | 14 ++++++-
 bigchaindb/backend/rethinkdb/query.py |  2 +-
 bigchaindb/core.py                    | 48 ++++++++++++++++++-----
 bigchaindb/models.py                  | 56 +++++++++++++++++++++++++++
 bigchaindb/pipelines/vote.py          |  2 +-
 tests/backend/mongodb/test_queries.py | 13 ++++---
 tests/backend/mongodb/test_schema.py  |  9 ++++-
 tests/backend/test_generics.py        |  4 +-
 tests/db/test_bigchain_api.py         |  2 +-
 tests/pipelines/test_vote.py          | 18 +++++++--
 12 files changed, 187 insertions(+), 32 deletions(-)

diff --git a/bigchaindb/backend/mongodb/query.py b/bigchaindb/backend/mongodb/query.py
index 74b9c35a..39d99d4a 100644
--- a/bigchaindb/backend/mongodb/query.py
+++ b/bigchaindb/backend/mongodb/query.py
@@ -7,7 +7,7 @@ from pymongo import ReturnDocument
 from bigchaindb import backend
 from bigchaindb.common.exceptions import CyclicBlockchainError
 from bigchaindb.common.transaction import Transaction
-from bigchaindb.backend.exceptions import DuplicateKeyError
+from bigchaindb.backend.exceptions import DuplicateKeyError, OperationError
 from bigchaindb.backend.utils import module_dispatch_registrar
 from bigchaindb.backend.mongodb.connection import MongoDBConnection
 
@@ -127,6 +127,7 @@ def get_txids_filtered(conn, asset_id, operation=None):
     return (elem['block']['transactions']['id'] for elem in cursor)
 
 
+# TODO: This doesn't seem to be used anywhere
 @register_query(MongoDBConnection)
 def get_asset_by_id(conn, asset_id):
     cursor = conn.run(
@@ -206,10 +207,10 @@ def get_votes_by_block_id_and_voter(conn, block_id, node_pubkey):
 
 
 @register_query(MongoDBConnection)
-def write_block(conn, block):
+def write_block(conn, block_dict):
     return conn.run(
         conn.collection('bigchain')
-        .insert_one(block.to_dict()))
+        .insert_one(block_dict))
 
 
 @register_query(MongoDBConnection)
@@ -220,6 +221,31 @@ def get_block(conn, block_id):
                   projection={'_id': False}))
 
 
+@register_query(MongoDBConnection)
+def write_assets(conn, assets):
+    try:
+        # unordered means that all the inserts will be attempted instead of
+        # stopping after the first error.
+        return conn.run(
+            conn.collection('assets')
+            .insert_many(assets, ordered=False))
+    # This can happen if we try to write the same asset multiple times.
+    # One case is when we write the same transaction into multiple blocks due
+    # to invalid blocks.
+    # The actual mongodb exception is a BulkWriteError due to a duplicated key
+    # in one of the inserts.
+    except OperationError:
+        return
+
+
+@register_query(MongoDBConnection)
+def get_assets(conn, asset_ids):
+    return conn.run(
+        conn.collection('assets')
+        .find({'id': {'$in': asset_ids}},
+              projection={'_id': False}))
+
+
 @register_query(MongoDBConnection)
 def count_blocks(conn):
     return conn.run(
@@ -252,7 +278,7 @@ def get_genesis_block(conn):
 
 
 @register_query(MongoDBConnection)
-def get_last_voted_block(conn, node_pubkey):
+def get_last_voted_block_id(conn, node_pubkey):
     last_voted = conn.run(
             conn.collection('votes')
             .find({'node_pubkey': node_pubkey},
@@ -261,7 +287,7 @@ def get_last_voted_block(conn, node_pubkey):
     # pymongo seems to return a cursor even if there are no results
     # so we actually need to check the count
     if last_voted.count() == 0:
-        return get_genesis_block(conn)
+        return get_genesis_block(conn)['id']
 
     mapping = {v['vote']['previous_block']: v['vote']['voting_for_block']
                for v in last_voted}
@@ -279,7 +305,7 @@ def get_last_voted_block(conn, node_pubkey):
         except KeyError:
             break
 
-    return get_block(conn, last_block_id)
+    return last_block_id
 
 
 @register_query(MongoDBConnection)
diff --git a/bigchaindb/backend/mongodb/schema.py b/bigchaindb/backend/mongodb/schema.py
index ad89f9bc..527476f0 100644
--- a/bigchaindb/backend/mongodb/schema.py
+++ b/bigchaindb/backend/mongodb/schema.py
@@ -27,7 +27,7 @@ def create_database(conn, dbname):
 
 @register_schema(MongoDBConnection)
 def create_tables(conn, dbname):
-    for table_name in ['bigchain', 'backlog', 'votes']:
+    for table_name in ['bigchain', 'backlog', 'votes', 'assets']:
         logger.info('Create `%s` table.', table_name)
         # create the table
         # TODO: read and write concerns can be declared here
@@ -39,6 +39,7 @@ def create_indexes(conn, dbname):
     create_bigchain_secondary_index(conn, dbname)
     create_backlog_secondary_index(conn, dbname)
     create_votes_secondary_index(conn, dbname)
+    create_assets_secondary_index(conn, dbname)
 
 
 @register_schema(MongoDBConnection)
@@ -102,3 +103,13 @@ def create_votes_secondary_index(conn, dbname):
                                               ASCENDING)],
                                             name='block_and_voter',
                                             unique=True)
+
+
+def create_assets_secondary_index(conn, dbname):
+    logger.info('Create `assets` secondary index.')
+
+    # is the first index redundant then?
+    # compound index to order votes by block id and node
+    conn.conn[dbname]['assets'].create_index('id',
+                                             name='asset_id',
+                                             unique=True)
diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 9aa653d7..8f1325ef 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -211,6 +211,18 @@ def get_block(connection, block_id):
     raise NotImplementedError
 
 
+@singledispatch
+def write_assets(connection, assets):
+    # TODO: write docstring
+    raise NotImplementedError
+
+
+@singledispatch
+def get_assets(connection, assets):
+    # TODO: write docstring
+    raise NotImplementedError
+
+
 @singledispatch
 def count_blocks(connection):
     """Count the number of blocks in the bigchain table.
@@ -259,7 +271,7 @@ def get_genesis_block(connection):
 
 
 @singledispatch
-def get_last_voted_block(connection, node_pubkey):
+def get_last_voted_block_id(connection, node_pubkey):
     """Get the last voted block for a specific node.
 
     Args:
diff --git a/bigchaindb/backend/rethinkdb/query.py b/bigchaindb/backend/rethinkdb/query.py
index 6011cc8c..be20442a 100644
--- a/bigchaindb/backend/rethinkdb/query.py
+++ b/bigchaindb/backend/rethinkdb/query.py
@@ -188,7 +188,7 @@ def get_genesis_block(connection):
 
 
 @register_query(RethinkDBConnection)
-def get_last_voted_block(connection, node_pubkey):
+def get_last_voted_block_id(connection, node_pubkey):
     try:
         # get the latest value for the vote timestamp (over all votes)
         max_timestamp = connection.run(
diff --git a/bigchaindb/core.py b/bigchaindb/core.py
index 5d2e9c03..c6ff5608 100644
--- a/bigchaindb/core.py
+++ b/bigchaindb/core.py
@@ -183,15 +183,23 @@ class Bigchain(object):
             include_status (bool): also return the status of the block
                        the return value is then a tuple: (block, status)
         """
-        block = backend.query.get_block(self.connection, block_id)
-        status = None
+        # get block from database
+        block_dict = backend.query.get_block(self.connection, block_id)
+        # get the asset ids from the block
+        if block_dict:
+            asset_ids = Block.get_asset_ids(block_dict)
+            # get the assets from the database
+            assets = self.get_assets(asset_ids)
+            # add the assets to the block transactions
+            block_dict = Block.couple_assets(block_dict, assets)
 
+        status = None
         if include_status:
-            if block:
-                status = self.block_election_status(block)
-            return block, status
+            if block_dict:
+                status = self.block_election_status(block_dict)
+            return block_dict, status
         else:
-            return block
+            return block_dict
 
     def get_transaction(self, txid, include_status=False):
         """Get the transaction with the specified `txid` (and optionally its status)
@@ -251,7 +259,13 @@ class Bigchain(object):
                 tx_status = self.TX_IN_BACKLOG
 
         if response:
-            response = Transaction.from_dict(response)
+            if tx_status == self.TX_IN_BACKLOG:
+                response = Transaction.from_dict(response)
+            else:
+                # If we are reading from the bigchain collection the asset is
+                # not in the transaction so we need to fetch the asset and
+                # reconstruct the transaction.
+                response = Transaction.from_db(self, response)
 
         if include_status:
             return response, tx_status
@@ -513,7 +527,14 @@ class Bigchain(object):
             block (Block): block to write to bigchain.
         """
 
-        return backend.query.write_block(self.connection, block)
+        # Decouple assets from block
+        assets, block_dict = block.decouple_assets()
+        # write the assets
+        if assets:
+            self.write_assets(assets)
+
+        # write the block
+        return backend.query.write_block(self.connection, block_dict)
 
     def prepare_genesis_block(self):
         """Prepare a genesis block."""
@@ -592,7 +613,9 @@ class Bigchain(object):
     def get_last_voted_block(self):
         """Returns the last block that this node voted on."""
 
-        return Block.from_dict(backend.query.get_last_voted_block(self.connection, self.me))
+        last_block_id = backend.query.get_last_voted_block_id(self.connection,
+                                                              self.me)
+        return Block.from_dict(self.get_block(last_block_id))
 
     def get_unvoted_blocks(self):
         """Return all the blocks that have not been voted on by this node.
@@ -616,3 +639,10 @@ class Bigchain(object):
         """Tally the votes on a block, and return the status:
            valid, invalid, or undecided."""
         return self.block_election(block)['status']
+
+    def get_assets(self, asset_ids):
+        # TODO: write docstrings
+        return backend.query.get_assets(self.connection, asset_ids)
+
+    def write_assets(self, assets):
+        return backend.query.write_assets(self.connection, assets)
diff --git a/bigchaindb/models.py b/bigchaindb/models.py
index 2f46ba20..5de56aaf 100644
--- a/bigchaindb/models.py
+++ b/bigchaindb/models.py
@@ -1,3 +1,5 @@
+from copy import deepcopy
+
 from bigchaindb.common.crypto import hash_data, PublicKey, PrivateKey
 from bigchaindb.common.exceptions import (InvalidHash, InvalidSignature,
                                           DoubleSpend, InputDoesNotExist,
@@ -84,6 +86,16 @@ class Transaction(Transaction):
         validate_transaction_schema(tx_body)
         return super().from_dict(tx_body)
 
+    @classmethod
+    def from_db(cls, bigchain, tx_dict):
+        # TODO: write docstring
+        if tx_dict['operation'] in [Transaction.CREATE, Transaction.CREATE]:
+            asset = bigchain.get_assets([tx_dict['id']])[0]
+            asset.pop('id')
+            tx_dict.update({'asset': asset})
+
+        return cls.from_dict(tx_dict)
+
 
 class Block(object):
     """Bundle a list of Transactions in a Block. Nodes vote on its validity.
@@ -300,5 +312,49 @@ class Block(object):
             'signature': self.signature,
         }
 
+    @classmethod
+    def from_db(cls, bigchain, block_dict):
+        asset_ids = cls.get_asset_ids(block_dict)
+        assets = bigchain.get_assets(asset_ids)
+        block_dict = cls.couple_assets(block_dict, assets)
+        return cls.from_dict(block_dict)
+
+    def decouple_assets(self):
+        # TODO: Write documentation
+        block_dict = deepcopy(self.to_dict())
+        assets = []
+        for transaction in block_dict['block']['transactions']:
+            if transaction['operation'] in [Transaction.CREATE,
+                                            Transaction.GENESIS]:
+                asset = transaction.pop('asset')
+                asset.update({'id': transaction['id']})
+                assets.append(asset)
+
+        return (assets, block_dict)
+
+    @staticmethod
+    def couple_assets(block_dict, assets):
+        # TODO: Write docstring
+        # create a dict with {'<txid>': asset}
+        assets = {asset.pop('id'): asset for asset in assets}
+        # add the assets to the block transactions
+        for transaction in block_dict['block']['transactions']:
+            if transaction['operation'] in [Transaction.CREATE,
+                                            Transaction.GENESIS]:
+                transaction.update({'asset': assets.get(transaction['id'],
+                                                        None)})
+        return block_dict
+
+    @staticmethod
+    def get_asset_ids(block_dict):
+        # TODO: Write docstring
+        asset_ids = []
+        for transaction in block_dict['block']['transactions']:
+            if transaction['operation'] in [Transaction.CREATE,
+                                            Transaction.GENESIS]:
+                asset_ids.append(transaction['id'])
+
+        return asset_ids
+
     def to_str(self):
         return serialize(self.to_dict())
diff --git a/bigchaindb/pipelines/vote.py b/bigchaindb/pipelines/vote.py
index 9664c520..e90ce6c4 100644
--- a/bigchaindb/pipelines/vote.py
+++ b/bigchaindb/pipelines/vote.py
@@ -50,7 +50,7 @@ class Vote:
     def validate_block(self, block):
         if not self.bigchain.has_previous_vote(block['id']):
             try:
-                block = Block.from_dict(block)
+                block = Block.from_db(self.bigchain, block)
             except (exceptions.InvalidHash):
                 # XXX: if a block is invalid we should skip the `validate_tx`
                 # step, but since we are in a pipeline we cannot just jump to
diff --git a/tests/backend/mongodb/test_queries.py b/tests/backend/mongodb/test_queries.py
index bd7e75f1..1363d9d7 100644
--- a/tests/backend/mongodb/test_queries.py
+++ b/tests/backend/mongodb/test_queries.py
@@ -269,7 +269,7 @@ def test_write_block(signed_create_tx):
 
     # create and write block
     block = Block(transactions=[signed_create_tx])
-    query.write_block(conn, block)
+    query.write_block(conn, block.to_dict())
 
     block_db = conn.db.bigchain.find_one({'id': block.id}, {'_id': False})
 
@@ -347,17 +347,18 @@ def test_get_genesis_block(genesis_block):
     from bigchaindb.backend import connect, query
     conn = connect()
 
-    assert query.get_genesis_block(conn) == genesis_block.to_dict()
+    assets, genesis_block_dict = genesis_block.decouple_assets()
+    assert query.get_genesis_block(conn) == genesis_block_dict
 
 
-def test_get_last_voted_block(genesis_block, signed_create_tx, b):
+def test_get_last_voted_block_id(genesis_block, signed_create_tx, b):
     from bigchaindb.backend import connect, query
     from bigchaindb.models import Block
     from bigchaindb.common.exceptions import CyclicBlockchainError
     conn = connect()
 
     # check that the last voted block is the genesis block
-    assert query.get_last_voted_block(conn, b.me) == genesis_block.to_dict()
+    assert query.get_last_voted_block_id(conn, b.me) == genesis_block.id
 
     # create and insert a new vote and block
     block = Block(transactions=[signed_create_tx])
@@ -365,7 +366,7 @@ def test_get_last_voted_block(genesis_block, signed_create_tx, b):
     vote = b.vote(block.id, genesis_block.id, True)
     conn.db.votes.insert_one(vote)
 
-    assert query.get_last_voted_block(conn, b.me) == block.to_dict()
+    assert query.get_last_voted_block_id(conn, b.me) == block.id
 
     # force a bad chain
     vote.pop('_id')
@@ -374,7 +375,7 @@ def test_get_last_voted_block(genesis_block, signed_create_tx, b):
     conn.db.votes.insert_one(vote)
 
     with pytest.raises(CyclicBlockchainError):
-        query.get_last_voted_block(conn, b.me)
+        query.get_last_voted_block_id(conn, b.me)
 
 
 def test_get_unvoted_blocks(signed_create_tx):
diff --git a/tests/backend/mongodb/test_schema.py b/tests/backend/mongodb/test_schema.py
index 71eac7ff..e3b320bd 100644
--- a/tests/backend/mongodb/test_schema.py
+++ b/tests/backend/mongodb/test_schema.py
@@ -18,7 +18,8 @@ def test_init_creates_db_tables_and_indexes():
     init_database()
 
     collection_names = conn.conn[dbname].collection_names()
-    assert sorted(collection_names) == ['backlog', 'bigchain', 'votes']
+    assert sorted(collection_names) == ['assets', 'backlog', 'bigchain',
+                                        'votes']
 
     indexes = conn.conn[dbname]['bigchain'].index_information().keys()
     assert sorted(indexes) == ['_id_', 'asset_id', 'block_timestamp', 'inputs',
@@ -31,6 +32,9 @@ def test_init_creates_db_tables_and_indexes():
     indexes = conn.conn[dbname]['votes'].index_information().keys()
     assert sorted(indexes) == ['_id_', 'block_and_voter']
 
+    indexes = conn.conn[dbname]['assets'].index_information().keys()
+    assert sorted(indexes) == ['_id_', 'asset_id']
+
 
 def test_init_database_fails_if_db_exists():
     import bigchaindb
@@ -62,7 +66,8 @@ def test_create_tables():
     schema.create_tables(conn, dbname)
 
     collection_names = conn.conn[dbname].collection_names()
-    assert sorted(collection_names) == ['backlog', 'bigchain', 'votes']
+    assert sorted(collection_names) == ['assets', 'backlog', 'bigchain',
+                                        'votes']
 
 
 def test_create_secondary_indexes():
diff --git a/tests/backend/test_generics.py b/tests/backend/test_generics.py
index 57a644ee..6a1e9447 100644
--- a/tests/backend/test_generics.py
+++ b/tests/backend/test_generics.py
@@ -30,12 +30,14 @@ def test_schema(schema_func_name, args_qty):
     ('write_block', 1),
     ('get_block', 1),
     ('write_vote', 1),
-    ('get_last_voted_block', 1),
+    ('get_last_voted_block_id', 1),
     ('get_unvoted_blocks', 1),
     ('get_spent', 2),
     ('get_votes_by_block_id_and_voter', 2),
     ('update_transaction', 2),
     ('get_transaction_from_block', 2),
+    ('write_assets', 1),
+    ('get_assets', 1),
 ))
 def test_query(query_func_name, args_qty):
     from bigchaindb.backend import query
diff --git a/tests/db/test_bigchain_api.py b/tests/db/test_bigchain_api.py
index 3f05385c..5960f171 100644
--- a/tests/db/test_bigchain_api.py
+++ b/tests/db/test_bigchain_api.py
@@ -383,7 +383,7 @@ class TestBigchainApi(object):
         from bigchaindb.backend import query
 
         genesis = query.get_genesis_block(b.connection)
-        genesis = Block.from_dict(genesis)
+        genesis = Block.from_db(b, genesis)
         gb = b.get_last_voted_block()
         assert gb == genesis
         assert b.validate_block(gb) == gb
diff --git a/tests/pipelines/test_vote.py b/tests/pipelines/test_vote.py
index 7df7ca11..29523035 100644
--- a/tests/pipelines/test_vote.py
+++ b/tests/pipelines/test_vote.py
@@ -20,6 +20,15 @@ def dummy_block(b):
     return block
 
 
+def decouple_assets(b, block):
+    # the block comming from the database does not contain the assets
+    # so we need to pass the block without the assets and store the assets
+    # so that the voting pipeline can reconstruct it
+    assets, block_dict = block.decouple_assets()
+    b.write_assets(assets)
+    return block_dict
+
+
 DUMMY_SHA3 = '0123456789abcdef' * 4
 
 
@@ -79,9 +88,10 @@ def test_vote_validate_block(b):
 
     tx = dummy_tx(b)
     block = b.create_block([tx])
+    block_dict = decouple_assets(b, block)
 
     vote_obj = vote.Vote()
-    validation = vote_obj.validate_block(block.to_dict())
+    validation = vote_obj.validate_block(block_dict)
     assert validation[0] == block.id
     for tx1, tx2 in zip(validation[1], block.transactions):
         assert tx1 == tx2
@@ -220,8 +230,9 @@ def test_valid_block_voting_multiprocessing(b, genesis_block, monkeypatch):
     vote_pipeline.setup(indata=inpipe, outdata=outpipe)
 
     block = dummy_block(b)
+    block_dict = decouple_assets(b, block)
 
-    inpipe.put(block.to_dict())
+    inpipe.put(block_dict)
     vote_pipeline.start()
     vote_out = outpipe.get()
     vote_pipeline.terminate()
@@ -257,6 +268,7 @@ def test_valid_block_voting_with_create_transaction(b,
 
     monkeypatch.setattr('time.time', lambda: 1111111111)
     block = b.create_block([tx])
+    block_dict = decouple_assets(b, block)
 
     inpipe = Pipe()
     outpipe = Pipe()
@@ -264,7 +276,7 @@ def test_valid_block_voting_with_create_transaction(b,
     vote_pipeline = vote.create_pipeline()
     vote_pipeline.setup(indata=inpipe, outdata=outpipe)
 
-    inpipe.put(block.to_dict())
+    inpipe.put(block_dict)
     vote_pipeline.start()
     vote_out = outpipe.get()
     vote_pipeline.terminate()

From 8c0dbeb28199ffab64619b281f04fb94e39fd05e Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Wed, 10 May 2017 17:55:43 +0200
Subject: [PATCH 09/26] Added asset decoupling support for rethinkdb

Updated schema.
Created queries for assets table.
Fixed tests.
---
 bigchaindb/backend/rethinkdb/query.py  | 25 +++++++++++++++++++------
 bigchaindb/backend/rethinkdb/schema.py |  2 +-
 bigchaindb/models.py                   |  3 ++-
 tests/backend/rethinkdb/test_schema.py |  3 ++-
 4 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/bigchaindb/backend/rethinkdb/query.py b/bigchaindb/backend/rethinkdb/query.py
index be20442a..417bcd93 100644
--- a/bigchaindb/backend/rethinkdb/query.py
+++ b/bigchaindb/backend/rethinkdb/query.py
@@ -6,6 +6,7 @@ import rethinkdb as r
 from bigchaindb import backend, utils
 from bigchaindb.common import exceptions
 from bigchaindb.common.transaction import Transaction
+from bigchaindb.common.utils import serialize
 from bigchaindb.backend.utils import module_dispatch_registrar
 from bigchaindb.backend.rethinkdb.connection import RethinkDBConnection
 
@@ -147,10 +148,10 @@ def get_votes_by_block_id_and_voter(connection, block_id, node_pubkey):
 
 
 @register_query(RethinkDBConnection)
-def write_block(connection, block):
+def write_block(connection, block_dict):
     return connection.run(
             r.table('bigchain')
-            .insert(r.json(block.to_str()), durability=WRITE_DURABILITY))
+            .insert(r.json(serialize(block_dict)), durability=WRITE_DURABILITY))
 
 
 @register_query(RethinkDBConnection)
@@ -158,6 +159,20 @@ def get_block(connection, block_id):
     return connection.run(r.table('bigchain').get(block_id))
 
 
+@register_query(RethinkDBConnection)
+def write_assets(connection, assets):
+    return connection.run(
+            r.table('assets')
+            .insert(assets, durability=WRITE_DURABILITY))
+
+
+@register_query(RethinkDBConnection)
+def get_assets(connection, asset_ids):
+    return connection.run(
+            r.table('assets', read_mode=READ_MODE)
+            .get_all(*asset_ids))
+
+
 @register_query(RethinkDBConnection)
 def count_blocks(connection):
     return connection.run(
@@ -203,7 +218,7 @@ def get_last_voted_block_id(connection, node_pubkey):
 
     except r.ReqlNonExistenceError:
         # return last vote if last vote exists else return Genesis block
-        return get_genesis_block(connection)
+        return get_genesis_block(connection)['id']
 
     # Now the fun starts. Since the resolution of timestamp is a second,
     # we might have more than one vote per timestamp. If this is the case
@@ -235,9 +250,7 @@ def get_last_voted_block_id(connection, node_pubkey):
         except KeyError:
             break
 
-    return connection.run(
-            r.table('bigchain', read_mode=READ_MODE)
-            .get(last_block_id))
+    return last_block_id
 
 
 @register_query(RethinkDBConnection)
diff --git a/bigchaindb/backend/rethinkdb/schema.py b/bigchaindb/backend/rethinkdb/schema.py
index 997ec5fc..8f0f6b9c 100644
--- a/bigchaindb/backend/rethinkdb/schema.py
+++ b/bigchaindb/backend/rethinkdb/schema.py
@@ -23,7 +23,7 @@ def create_database(connection, dbname):
 
 @register_schema(RethinkDBConnection)
 def create_tables(connection, dbname):
-    for table_name in ['bigchain', 'backlog', 'votes']:
+    for table_name in ['bigchain', 'backlog', 'votes', 'assets']:
         logger.info('Create `%s` table.', table_name)
         connection.run(r.db(dbname).table_create(table_name))
 
diff --git a/bigchaindb/models.py b/bigchaindb/models.py
index 5de56aaf..81ca898c 100644
--- a/bigchaindb/models.py
+++ b/bigchaindb/models.py
@@ -90,7 +90,8 @@ class Transaction(Transaction):
     def from_db(cls, bigchain, tx_dict):
         # TODO: write docstring
         if tx_dict['operation'] in [Transaction.CREATE, Transaction.CREATE]:
-            asset = bigchain.get_assets([tx_dict['id']])[0]
+            # TODO: Maybe replace this call to a call to get_asset_by_id
+            asset = list(bigchain.get_assets([tx_dict['id']]))[0]
             asset.pop('id')
             tx_dict.update({'asset': asset})
 
diff --git a/tests/backend/rethinkdb/test_schema.py b/tests/backend/rethinkdb/test_schema.py
index e19dfdc2..6f77b672 100644
--- a/tests/backend/rethinkdb/test_schema.py
+++ b/tests/backend/rethinkdb/test_schema.py
@@ -63,7 +63,8 @@ def test_create_tables():
     assert conn.run(r.db(dbname).table_list().contains('bigchain')) is True
     assert conn.run(r.db(dbname).table_list().contains('backlog')) is True
     assert conn.run(r.db(dbname).table_list().contains('votes')) is True
-    assert len(conn.run(r.db(dbname).table_list())) == 3
+    assert conn.run(r.db(dbname).table_list().contains('assets')) is True
+    assert len(conn.run(r.db(dbname).table_list())) == 4
 
 
 @pytest.mark.bdb

From aacba571f85f317882547c97b8c132281cfae2c0 Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Thu, 11 May 2017 11:38:07 +0200
Subject: [PATCH 10/26] Added docstrings and tests to new methods

---
 bigchaindb/backend/mongodb/schema.py  |   4 +-
 bigchaindb/backend/query.py           |  21 +++-
 bigchaindb/models.py                  |  51 +++++++++-
 tests/backend/mongodb/test_queries.py |  46 +++++++++
 tests/test_block_model.py             | 133 ++++++++++++++++++++++++++
 5 files changed, 247 insertions(+), 8 deletions(-)

diff --git a/bigchaindb/backend/mongodb/schema.py b/bigchaindb/backend/mongodb/schema.py
index 527476f0..12b873e0 100644
--- a/bigchaindb/backend/mongodb/schema.py
+++ b/bigchaindb/backend/mongodb/schema.py
@@ -108,8 +108,8 @@ def create_votes_secondary_index(conn, dbname):
 def create_assets_secondary_index(conn, dbname):
     logger.info('Create `assets` secondary index.')
 
-    # is the first index redundant then?
-    # compound index to order votes by block id and node
+    # unique index on the id of the asset.
+    # the id is the txid of the transaction that created the asset
     conn.conn[dbname]['assets'].create_index('id',
                                              name='asset_id',
                                              unique=True)
diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 8f1325ef..5c37647c 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -213,13 +213,28 @@ def get_block(connection, block_id):
 
 @singledispatch
 def write_assets(connection, assets):
-    # TODO: write docstring
+    """Write a list of assets to the assets table.
+
+    Args:
+        assets (list): a list of assets to write.
+
+    Returns:
+        The database response.
+    """
     raise NotImplementedError
 
 
 @singledispatch
-def get_assets(connection, assets):
-    # TODO: write docstring
+def get_assets(connection, asset_ids):
+    """Get a list of assets from the assets table.
+
+    Args:
+        asset_ids (list): a of list of ids for the assets to be retrieved from
+        the database.
+
+    Returns:
+        assets (list): the list of returned assets.
+    """
     raise NotImplementedError
 
 
diff --git a/bigchaindb/models.py b/bigchaindb/models.py
index 81ca898c..53266930 100644
--- a/bigchaindb/models.py
+++ b/bigchaindb/models.py
@@ -315,13 +315,33 @@ class Block(object):
 
     @classmethod
     def from_db(cls, bigchain, block_dict):
+        """
+        Helper method that reconstructs a block_dict that was returned from
+        the database. If checks what asset_ids to retrieve, retrieves the
+        assets from the assets table and reconstructs the block.
+
+        Args:
+            bigchain (:class:`~bigchaindb.Bigchain`): An instance of Bigchain
+                used to perform database queries.
+
+        Returns:
+            :class:`~Block`
+
+        """
         asset_ids = cls.get_asset_ids(block_dict)
         assets = bigchain.get_assets(asset_ids)
         block_dict = cls.couple_assets(block_dict, assets)
         return cls.from_dict(block_dict)
 
     def decouple_assets(self):
-        # TODO: Write documentation
+        """
+        Extracts the assets from the `CREATE` transactions in the block.
+
+        Returns:
+            tuple: (assets, block) with the assets being a list of dicts and
+            the block being the dict of the block with no assets in the CREATE
+            transactions.
+        """
         block_dict = deepcopy(self.to_dict())
         assets = []
         for transaction in block_dict['block']['transactions']:
@@ -335,7 +355,20 @@ class Block(object):
 
     @staticmethod
     def couple_assets(block_dict, assets):
-        # TODO: Write docstring
+        """
+        Give a block_dict with not assets (as returned from a database call)
+        and a list of assets, reconstruct the original block by puting the
+        assets back into the `CREATE` transactions in the block.
+
+        Args:
+            block_dict (:obj:`dict`): The block dict as returned from a
+                database call.
+            assets (:obj:`list` of :obj:`dict`): A list of assets returned from
+                a database call.
+
+        Returns:
+            dict: The dict of the reconstructed block.
+        """
         # create a dict with {'<txid>': asset}
         assets = {asset.pop('id'): asset for asset in assets}
         # add the assets to the block transactions
@@ -348,7 +381,19 @@ class Block(object):
 
     @staticmethod
     def get_asset_ids(block_dict):
-        # TODO: Write docstring
+        """
+        Given a block_dict return all the asset_ids for that block (the txid
+        of CREATE transactions). Usefull to know which assets to retrieve
+        from the database to reconstruct the block.
+
+        Args:
+            block_dict (:obj:`dict`): The block dict as returned from a
+                database call.
+
+        Returns:
+            list: The list of asset_ids in the block.
+
+        """
         asset_ids = []
         for transaction in block_dict['block']['transactions']:
             if transaction['operation'] in [Transaction.CREATE,
diff --git a/tests/backend/mongodb/test_queries.py b/tests/backend/mongodb/test_queries.py
index 1363d9d7..c43c5fa4 100644
--- a/tests/backend/mongodb/test_queries.py
+++ b/tests/backend/mongodb/test_queries.py
@@ -1,4 +1,7 @@
+from copy import deepcopy
+
 import pytest
+import pymongo
 
 pytestmark = pytest.mark.bdb
 
@@ -418,3 +421,46 @@ def test_get_txids_filtered(signed_create_tx, signed_transfer_tx):
     # Test get by asset and TRANSFER
     txids = set(query.get_txids_filtered(conn, asset_id, Transaction.TRANSFER))
     assert txids == {signed_transfer_tx.id}
+
+
+def test_write_assets():
+    from bigchaindb.backend import connect, query
+    conn = connect()
+
+    assets = [
+        {'id': 1, 'data': '1'},
+        {'id': 2, 'data': '2'},
+        {'id': 3, 'data': '3'},
+        # Duplicated id. Should not be written to the database
+        {'id': 1, 'data': '1'},
+    ]
+
+    # write the assets
+    query.write_assets(conn, deepcopy(assets))
+
+    # check that 3 assets were written to the database
+    cursor = conn.db.assets.find({}, projection={'_id': False})\
+                           .sort('id', pymongo.ASCENDING)
+
+    assert cursor.count() == 3
+    assert list(cursor) == assets[:-1]
+
+
+def test_get_assets():
+    from bigchaindb.backend import connect, query
+    conn = connect()
+
+    assets = [
+        {'id': 1, 'data': '1'},
+        {'id': 2, 'data': '2'},
+        {'id': 3, 'data': '3'},
+    ]
+
+    # write the assets
+    conn.db.assets.insert_many(deepcopy(assets), ordered=False)
+
+    # read only 2 assets
+    cursor = query.get_assets(conn, [1, 3])
+
+    assert cursor.count() == 2
+    assert list(cursor.sort('id', pymongo.ASCENDING)) == assets[::2]
diff --git a/tests/test_block_model.py b/tests/test_block_model.py
index 6e559cb2..981a64d7 100644
--- a/tests/test_block_model.py
+++ b/tests/test_block_model.py
@@ -153,3 +153,136 @@ class TestBlockModel(object):
         block = b.create_block([tx, tx])
         with raises(DuplicateTransaction):
             block._validate_block(b)
+
+    def test_decouple_assets(self, b):
+        from bigchaindb.models import Block, Transaction
+
+        assets = [
+            {'msg': '1'},
+            {'msg': '2'},
+            {'msg': '3'},
+        ]
+
+        txs = []
+        # create 3 assets
+        for asset in assets:
+            tx = Transaction.create([b.me], [([b.me], 1)], asset=asset)
+            txs.append(tx)
+
+        # create a `TRANSFER` transaction.
+        # the asset in `TRANSFER` transactions is not extracted
+        tx = Transaction.transfer(txs[0].to_inputs(), [([b.me], 1)],
+                                  asset_id=txs[0].id)
+        txs.append(tx)
+
+        # create the block
+        block = Block(txs)
+        # decouple assets
+        assets_from_block, block_dict = block.decouple_assets()
+
+        assert len(assets_from_block) == 3
+        for i in range(3):
+            assert assets_from_block[i]['data'] == assets[i]
+            assert assets_from_block[i]['id'] == txs[i].id
+
+        # check the `TRANSFER` transaction was not changed
+        assert block.transactions[3].to_dict() == \
+            block_dict['block']['transactions'][3]
+
+    def test_couple_assets(self, b):
+        from bigchaindb.models import Block, Transaction
+
+        assets = [
+            {'msg': '1'},
+            {'msg': '2'},
+            {'msg': '3'},
+        ]
+
+        txs = []
+        # create 3 assets
+        for asset in assets:
+            tx = Transaction.create([b.me], [([b.me], 1)], asset=asset)
+            txs.append(tx)
+
+        # create a `TRANSFER` transaction.
+        # the asset in `TRANSFER` transactions is not extracted
+        tx = Transaction.transfer(txs[0].to_inputs(), [([b.me], 1)],
+                                  asset_id=txs[0].id)
+        txs.append(tx)
+
+        # create the block
+        block = Block(txs)
+        # decouple assets
+        assets_from_block, block_dict = block.decouple_assets()
+
+        # reconstruct the block
+        block_dict_reconstructed = Block.couple_assets(block_dict,
+                                                       assets_from_block)
+
+        # check that the reconstructed block is the as the original block
+        assert block == Block.from_dict(block_dict_reconstructed)
+
+    def test_get_asset_ids(self, b):
+        from bigchaindb.models import Block, Transaction
+
+        assets = [
+            {'msg': '1'},
+            {'msg': '2'},
+            {'msg': '3'},
+        ]
+
+        txs = []
+        # create 3 assets
+        for asset in assets:
+            tx = Transaction.create([b.me], [([b.me], 1)], asset=asset)
+            txs.append(tx)
+
+        # create a `TRANSFER` transaction.
+        # the asset in `TRANSFER` transactions is not extracted
+        tx = Transaction.transfer(txs[0].to_inputs(), [([b.me], 1)],
+                                  asset_id=txs[0].id)
+        txs.append(tx)
+
+        # create the block
+        block = Block(txs)
+        # decouple assets
+        assets_from_block, block_dict = block.decouple_assets()
+
+        # get the asset_ids and check that they are the same as the `CREATE`
+        # transactions
+        asset_ids = Block.get_asset_ids(block_dict)
+        assert asset_ids == [tx.id for tx in txs[:-1]]
+
+    def test_from_db(self, b):
+        from bigchaindb.models import Block, Transaction
+
+        assets = [
+            {'msg': '1'},
+            {'msg': '2'},
+            {'msg': '3'},
+        ]
+
+        txs = []
+        # create 3 assets
+        for asset in assets:
+            tx = Transaction.create([b.me], [([b.me], 1)], asset=asset)
+            txs.append(tx)
+
+        # create a `TRANSFER` transaction.
+        # the asset in `TRANSFER` transactions is not extracted
+        tx = Transaction.transfer(txs[0].to_inputs(), [([b.me], 1)],
+                                  asset_id=txs[0].id)
+        txs.append(tx)
+
+        # create the block
+        block = Block(txs)
+        # decouple assets
+        assets_from_block, block_dict = block.decouple_assets()
+
+        # write the assets and block separatedly
+        b.write_assets(assets_from_block)
+        b.write_block(block)
+
+        # check the reconstructed block is the same as the original block
+        block_from_db = Block.from_db(b, block_dict)
+        assert block == block_from_db

From eb94181e1bc0ed904b25a3a1c626c5f2d863993b Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Thu, 11 May 2017 12:00:01 +0200
Subject: [PATCH 11/26] Fixed tests.

Updated fixtures to flush the assets table after each test.
---
 tests/test_block_model.py | 2 ++
 tests/utils.py            | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/tests/test_block_model.py b/tests/test_block_model.py
index 981a64d7..f2b307de 100644
--- a/tests/test_block_model.py
+++ b/tests/test_block_model.py
@@ -1,3 +1,4 @@
+import pytest
 from pytest import raises
 
 
@@ -253,6 +254,7 @@ class TestBlockModel(object):
         asset_ids = Block.get_asset_ids(block_dict)
         assert asset_ids == [tx.id for tx in txs[:-1]]
 
+    @pytest.mark.bdb
     def test_from_db(self, b):
         from bigchaindb.models import Block, Transaction
 
diff --git a/tests/utils.py b/tests/utils.py
index 53ffd86b..9af72a5d 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -32,6 +32,7 @@ def flush_rethink_db(connection, dbname):
         connection.run(r.db(dbname).table('bigchain').delete())
         connection.run(r.db(dbname).table('backlog').delete())
         connection.run(r.db(dbname).table('votes').delete())
+        connection.run(r.db(dbname).table('assets').delete())
     except r.ReqlOpFailedError:
         pass
 
@@ -41,6 +42,7 @@ def flush_mongo_db(connection, dbname):
     connection.conn[dbname].bigchain.delete_many({})
     connection.conn[dbname].backlog.delete_many({})
     connection.conn[dbname].votes.delete_many({})
+    connection.conn[dbname].assets.delete_many({})
 
 
 @singledispatch

From ce414e46f3da825143c7df3c72295a68f61f073d Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Thu, 11 May 2017 12:29:08 +0200
Subject: [PATCH 12/26] Added missing docstrings. Fixed typos.

---
 bigchaindb/backend/query.py |  4 ++--
 bigchaindb/core.py          | 18 +++++++++++++++++-
 bigchaindb/models.py        | 22 +++++++++++++++++++---
 tests/test_block_model.py   |  2 +-
 4 files changed, 39 insertions(+), 7 deletions(-)

diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 5c37647c..8245fb3d 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -293,8 +293,8 @@ def get_last_voted_block_id(connection, node_pubkey):
         node_pubkey (str): base58 encoded public key.
 
     Returns:
-        The last block the node has voted on. If the node didn't cast
-        any vote then the genesis block is returned.
+        The last block id the node has voted on. If the node didn't cast
+        any vote then the genesis block id is returned.
     """
 
     raise NotImplementedError
diff --git a/bigchaindb/core.py b/bigchaindb/core.py
index c6ff5608..1cd21222 100644
--- a/bigchaindb/core.py
+++ b/bigchaindb/core.py
@@ -641,8 +641,24 @@ class Bigchain(object):
         return self.block_election(block)['status']
 
     def get_assets(self, asset_ids):
-        # TODO: write docstrings
+        """
+        Return a list of assets that match the asset_ids
+
+        Args:
+            asset_ids (:obj:`list` of :obj:`str`): A list of asset_ids to
+                retrieve from the database.
+
+        Returs:
+            list: The list of assets returned from the database.
+        """
         return backend.query.get_assets(self.connection, asset_ids)
 
     def write_assets(self, assets):
+        """
+        Writes a list of assets into the database.
+
+        Args:
+            assets (:obj:`list` of :obj:`dict`): A list of assets to write to
+                the database.
+        """
         return backend.query.write_assets(self.connection, assets)
diff --git a/bigchaindb/models.py b/bigchaindb/models.py
index 53266930..c77c3338 100644
--- a/bigchaindb/models.py
+++ b/bigchaindb/models.py
@@ -88,8 +88,22 @@ class Transaction(Transaction):
 
     @classmethod
     def from_db(cls, bigchain, tx_dict):
-        # TODO: write docstring
-        if tx_dict['operation'] in [Transaction.CREATE, Transaction.CREATE]:
+        """
+        Helper method that reconstructs a transaction dict that was returned
+        from the database. It checks what asset_id to retrieve, retrieves the
+        asset from the asset table and reconstructs the transaction.
+
+        Args:
+            bigchain (:class:`~bigchaindb.Bigchain`): An instance of Bigchain
+                used to perform database queries.
+            tx_dict (:obj:`dict`): The transaction dict as returned from the
+                database.
+
+        Returns:
+            :class:`~Transaction`
+
+        """
+        if tx_dict['operation'] in [Transaction.CREATE, Transaction.GENESIS]:
             # TODO: Maybe replace this call to a call to get_asset_by_id
             asset = list(bigchain.get_assets([tx_dict['id']]))[0]
             asset.pop('id')
@@ -317,12 +331,14 @@ class Block(object):
     def from_db(cls, bigchain, block_dict):
         """
         Helper method that reconstructs a block_dict that was returned from
-        the database. If checks what asset_ids to retrieve, retrieves the
+        the database. It checks what asset_ids to retrieve, retrieves the
         assets from the assets table and reconstructs the block.
 
         Args:
             bigchain (:class:`~bigchaindb.Bigchain`): An instance of Bigchain
                 used to perform database queries.
+            block_dict(:obj:`dict`): The block dict as returned from the
+                database.
 
         Returns:
             :class:`~Block`
diff --git a/tests/test_block_model.py b/tests/test_block_model.py
index f2b307de..0824c40f 100644
--- a/tests/test_block_model.py
+++ b/tests/test_block_model.py
@@ -281,7 +281,7 @@ class TestBlockModel(object):
         # decouple assets
         assets_from_block, block_dict = block.decouple_assets()
 
-        # write the assets and block separatedly
+        # write the assets and block separately
         b.write_assets(assets_from_block)
         b.write_block(block)
 

From ccaae91601d174dbede2102458410597ec14a8ed Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Fri, 12 May 2017 15:22:11 +0200
Subject: [PATCH 13/26] Added full text search support for mongodb.

- Create widlcard text index for the assets collection.
- Created backend query to to text search on assets collection.
- Added and updated tests.
---
 bigchaindb/backend/mongodb/query.py   | 25 ++++++++
 bigchaindb/backend/mongodb/schema.py  |  5 +-
 bigchaindb/backend/query.py           |  8 +++
 tests/backend/mongodb/test_queries.py | 84 +++++++++++++++++++++++++++
 tests/backend/mongodb/test_schema.py  |  2 +-
 5 files changed, 122 insertions(+), 2 deletions(-)

diff --git a/bigchaindb/backend/mongodb/query.py b/bigchaindb/backend/mongodb/query.py
index 39d99d4a..3d989a3d 100644
--- a/bigchaindb/backend/mongodb/query.py
+++ b/bigchaindb/backend/mongodb/query.py
@@ -327,3 +327,28 @@ def get_unvoted_blocks(conn, node_pubkey):
                 'votes': False, '_id': False
             }}
         ]))
+
+
+@register_query(MongoDBConnection)
+def text_search(conn, search, language='english', case_sensitive=False,
+                diacritic_sensitive=False, text_score=False, limit=0):
+    cursor = conn.run(
+        conn.collection('assets')
+        .find({'$text': {
+                '$search': search,
+                '$language': language,
+                '$caseSensitive': case_sensitive,
+                '$diacriticSensitive': diacritic_sensitive}},
+              {'score': {'$meta': 'textScore'}, '_id': False})
+        .sort([('score', {'$meta': 'textScore'})])
+        .limit(limit))
+
+    if text_score:
+        return cursor
+    else:
+        return (_remove_text_score(asset) for asset in cursor)
+
+
+def _remove_text_score(asset):
+    asset.pop('score', None)
+    return asset
diff --git a/bigchaindb/backend/mongodb/schema.py b/bigchaindb/backend/mongodb/schema.py
index 12b873e0..6c54bfd8 100644
--- a/bigchaindb/backend/mongodb/schema.py
+++ b/bigchaindb/backend/mongodb/schema.py
@@ -2,7 +2,7 @@
 
 import logging
 
-from pymongo import ASCENDING, DESCENDING
+from pymongo import ASCENDING, DESCENDING, TEXT
 
 from bigchaindb import backend
 from bigchaindb.common import exceptions
@@ -113,3 +113,6 @@ def create_assets_secondary_index(conn, dbname):
     conn.conn[dbname]['assets'].create_index('id',
                                              name='asset_id',
                                              unique=True)
+
+    # full text search index
+    conn.conn[dbname]['assets'].create_index([('$**', TEXT)], name='text')
diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 8245fb3d..705b0306 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -325,3 +325,11 @@ def get_txids_filtered(connection, asset_id, operation=None):
     """
 
     raise NotImplementedError
+
+
+@singledispatch
+def text_search(conn, search, language='english', case_sensitive=False,
+                diacritic_sensitive=False, text_score=False, limit=0):
+    # TODO: docstring
+
+    raise NotImplementedError
diff --git a/tests/backend/mongodb/test_queries.py b/tests/backend/mongodb/test_queries.py
index c43c5fa4..9b2ad1cf 100644
--- a/tests/backend/mongodb/test_queries.py
+++ b/tests/backend/mongodb/test_queries.py
@@ -464,3 +464,87 @@ def test_get_assets():
 
     assert cursor.count() == 2
     assert list(cursor.sort('id', pymongo.ASCENDING)) == assets[::2]
+
+
+def test_text_search():
+    from bigchaindb.backend import connect, query
+    conn = connect()
+
+    # Example data and tests cases taken from the mongodb documentation
+    # https://docs.mongodb.com/manual/reference/operator/query/text/
+    assets = [
+        {'id': 1, 'subject': 'coffee', 'author': 'xyz', 'views': 50},
+        {'id': 2, 'subject': 'Coffee Shopping', 'author': 'efg', 'views': 5},
+        {'id': 3, 'subject': 'Baking a cake', 'author': 'abc', 'views': 90},
+        {'id': 4, 'subject': 'baking', 'author': 'xyz', 'views': 100},
+        {'id': 5, 'subject': 'Café Con Leche', 'author': 'abc', 'views': 200},
+        {'id': 6, 'subject': 'Сырники', 'author': 'jkl', 'views': 80},
+        {'id': 7, 'subject': 'coffee and cream', 'author': 'efg', 'views': 10},
+        {'id': 8, 'subject': 'Cafe con Leche', 'author': 'xyz', 'views': 10}
+    ]
+
+    # insert the assets
+    conn.db.assets.insert_many(deepcopy(assets), ordered=False)
+
+    # test search single word
+    assert list(query.text_search(conn, 'coffee')) == [
+        {'id': 1, 'subject': 'coffee', 'author': 'xyz', 'views': 50},
+        {'id': 2, 'subject': 'Coffee Shopping', 'author': 'efg', 'views': 5},
+        {'id': 7, 'subject': 'coffee and cream', 'author': 'efg', 'views': 10},
+    ]
+
+    # match any of the search terms
+    assert list(query.text_search(conn, 'bake coffee cake')) == [
+        {'author': 'abc', 'id': 3, 'subject': 'Baking a cake', 'views': 90},
+        {'author': 'xyz', 'id': 1, 'subject': 'coffee', 'views': 50},
+        {'author': 'xyz', 'id': 4, 'subject': 'baking', 'views': 100},
+        {'author': 'efg', 'id': 2, 'subject': 'Coffee Shopping', 'views': 5},
+        {'author': 'efg', 'id': 7, 'subject': 'coffee and cream', 'views': 10}
+    ]
+
+    # search for a phrase
+    assert list(query.text_search(conn, '\"coffee shop\"')) == [
+        {'id': 2, 'subject': 'Coffee Shopping', 'author': 'efg', 'views': 5},
+    ]
+
+    # exclude documents that contain a term
+    assert list(query.text_search(conn, 'coffee -shop')) == [
+        {'id': 1, 'subject': 'coffee', 'author': 'xyz', 'views': 50},
+        {'id': 7, 'subject': 'coffee and cream', 'author': 'efg', 'views': 10},
+    ]
+
+    # search different language
+    assert list(query.text_search(conn, 'leche', language='es')) == [
+        {'id': 5, 'subject': 'Café Con Leche', 'author': 'abc', 'views': 200},
+        {'id': 8, 'subject': 'Cafe con Leche', 'author': 'xyz', 'views': 10}
+    ]
+
+    # case and diacritic insensitive search
+    assert list(query.text_search(conn, 'сы́рники CAFÉS')) == [
+        {'id': 6, 'subject': 'Сырники', 'author': 'jkl', 'views': 80},
+        {'id': 5, 'subject': 'Café Con Leche', 'author': 'abc', 'views': 200},
+        {'id': 8, 'subject': 'Cafe con Leche', 'author': 'xyz', 'views': 10}
+    ]
+
+    # case sensitive search
+    assert list(query.text_search(conn, 'Coffee', case_sensitive=True)) == [
+        {'id': 2, 'subject': 'Coffee Shopping', 'author': 'efg', 'views': 5},
+    ]
+
+    # diacritic sensitive search
+    assert list(query.text_search(conn, 'CAFÉ', diacritic_sensitive=True)) == [
+        {'id': 5, 'subject': 'Café Con Leche', 'author': 'abc', 'views': 200},
+    ]
+
+    # return text score
+    assert list(query.text_search(conn, 'coffee', text_score=True)) == [
+        {'id': 1, 'subject': 'coffee', 'author': 'xyz', 'views': 50, 'score': 1.0},
+        {'id': 2, 'subject': 'Coffee Shopping', 'author': 'efg', 'views': 5, 'score': 0.75},
+        {'id': 7, 'subject': 'coffee and cream', 'author': 'efg', 'views': 10, 'score': 0.75},
+    ]
+
+    # limit search result
+    assert list(query.text_search(conn, 'coffee', limit=2)) == [
+        {'id': 1, 'subject': 'coffee', 'author': 'xyz', 'views': 50},
+        {'id': 2, 'subject': 'Coffee Shopping', 'author': 'efg', 'views': 5},
+    ]
diff --git a/tests/backend/mongodb/test_schema.py b/tests/backend/mongodb/test_schema.py
index e3b320bd..e11dbfe8 100644
--- a/tests/backend/mongodb/test_schema.py
+++ b/tests/backend/mongodb/test_schema.py
@@ -33,7 +33,7 @@ def test_init_creates_db_tables_and_indexes():
     assert sorted(indexes) == ['_id_', 'block_and_voter']
 
     indexes = conn.conn[dbname]['assets'].index_information().keys()
-    assert sorted(indexes) == ['_id_', 'asset_id']
+    assert sorted(indexes) == ['_id_', 'asset_id', 'text']
 
 
 def test_init_database_fails_if_db_exists():

From edbe5deb466de8c66fb838d6f990b3df10460876 Mon Sep 17 00:00:00 2001
From: Troy McConaghy <troy@bigchaindb.com>
Date: Mon, 15 May 2017 15:25:01 +0200
Subject: [PATCH 14/26] docs: moved old cloud depl. templates to Appendices &
 edited intros

---
 .../azure-quickstart-template.md               |  2 +-
 docs/server/source/appendices/index.rst        |  3 +++
 .../template-ansible.md                        |  4 ++--
 .../template-terraform-aws.md                  |  4 ++--
 .../cloud-deployment-templates/index.rst       | 18 +++++++++---------
 docs/server/source/index.rst                   |  4 ++--
 6 files changed, 19 insertions(+), 16 deletions(-)
 rename docs/server/source/{cloud-deployment-templates => appendices}/azure-quickstart-template.md (93%)
 rename docs/server/source/{cloud-deployment-templates => appendices}/template-ansible.md (94%)
 rename docs/server/source/{cloud-deployment-templates => appendices}/template-terraform-aws.md (95%)

diff --git a/docs/server/source/cloud-deployment-templates/azure-quickstart-template.md b/docs/server/source/appendices/azure-quickstart-template.md
similarity index 93%
rename from docs/server/source/cloud-deployment-templates/azure-quickstart-template.md
rename to docs/server/source/appendices/azure-quickstart-template.md
index 1bf35a31..59f52fd3 100644
--- a/docs/server/source/cloud-deployment-templates/azure-quickstart-template.md
+++ b/docs/server/source/appendices/azure-quickstart-template.md
@@ -1,6 +1,6 @@
 # Azure Quickstart Template
 
-If you didn't read the introduction to the [cloud deployment templates](index.html), please do that now. The main point is that they're not for deploying a production node; they can be used as a starting point.
+This page outlines how to run a single BigchainDB node on the Microsoft Azure public cloud, with RethinkDB as the database backend. It uses an Azure Quickstart Template. That template is dated because we now recommend using MongoDB instead of RethinkDB. That's why we moved this page to the Appendices.
 
 Note: There was an Azure quickstart template in the `blockchain` directory of Microsoft's `Azure/azure-quickstart-templates` repository on GitHub. It's gone now; it was replaced by the one described here.
 
diff --git a/docs/server/source/appendices/index.rst b/docs/server/source/appendices/index.rst
index 1c969c05..f5931e64 100755
--- a/docs/server/source/appendices/index.rst
+++ b/docs/server/source/appendices/index.rst
@@ -18,6 +18,9 @@ Appendices
    backend
    commands
    aws-setup
+   template-terraform-aws
+   template-ansible
+   azure-quickstart-template
    generate-key-pair-for-ssh
    firewall-notes
    ntp-notes
diff --git a/docs/server/source/cloud-deployment-templates/template-ansible.md b/docs/server/source/appendices/template-ansible.md
similarity index 94%
rename from docs/server/source/cloud-deployment-templates/template-ansible.md
rename to docs/server/source/appendices/template-ansible.md
index f296a2cf..508d0555 100644
--- a/docs/server/source/cloud-deployment-templates/template-ansible.md
+++ b/docs/server/source/appendices/template-ansible.md
@@ -1,9 +1,9 @@
 # Template: Ansible Playbook to Run a BigchainDB Node on an Ubuntu Machine
 
-If you didn't read the introduction to the [cloud deployment templates](index.html), please do that now. The main point is that they're not for deploying a production node; they can be used as a starting point.
-
 This page explains how to use [Ansible](https://www.ansible.com/) to install, configure and run all the software needed to run a one-machine BigchainDB node on a server running Ubuntu 16.04.
 
+**Note: We're not actively maintaining the associated Ansible files (e.g. playbooks). They are RethinkDB-specific, even though we now recommend using MongoDB. You may find the old Ansible stuff useful nevertheless, which is why we moved this page to the Appendices rather than deleting it.**
+
 
 ## Install Ansible
 
diff --git a/docs/server/source/cloud-deployment-templates/template-terraform-aws.md b/docs/server/source/appendices/template-terraform-aws.md
similarity index 95%
rename from docs/server/source/cloud-deployment-templates/template-terraform-aws.md
rename to docs/server/source/appendices/template-terraform-aws.md
index d4a22e83..055a5ee3 100644
--- a/docs/server/source/cloud-deployment-templates/template-terraform-aws.md
+++ b/docs/server/source/appendices/template-terraform-aws.md
@@ -1,8 +1,8 @@
 # Template: Using Terraform to Provision an Ubuntu Machine on AWS
 
-If you didn't read the introduction to the [cloud deployment templates](index.html), please do that now. The main point is that they're not for deploying a production node; they can be used as a starting point.
+This page explains a way to use [Terraform](https://www.terraform.io/) to provision an Ubuntu machine (i.e. an EC2 instance with Ubuntu 16.04) and other resources on [AWS](https://aws.amazon.com/). That machine can then be used to host a one-machine BigchainDB node, for example.
 
-This page explains a way to use [Terraform](https://www.terraform.io/) to provision an Ubuntu machine (i.e. an EC2 instance with Ubuntu 16.04) and other resources on [AWS](https://aws.amazon.com/). That machine can then be used to host a one-machine BigchainDB node.
+**Note: We're not actively maintaining the associated Terraform files. You may find them useful nevertheless, which is why we moved this page to the Appendices rather than deleting it.**
 
 
 ## Install Terraform
diff --git a/docs/server/source/cloud-deployment-templates/index.rst b/docs/server/source/cloud-deployment-templates/index.rst
index 41eec0ed..34a4b28b 100644
--- a/docs/server/source/cloud-deployment-templates/index.rst
+++ b/docs/server/source/cloud-deployment-templates/index.rst
@@ -1,18 +1,18 @@
-Cloud Deployment Templates
-==========================
+Production Deployment Template
+==============================
 
-We have some "templates" to deploy a basic, working, but bare-bones BigchainDB node on various cloud providers. They should *not* be used as-is to deploy a node for production. They can be used as a starting point.
+This section outlines how *we* deploy production BigchainDB nodes and clusters
+on Microsoft Azure
+using Kubernetes.
+We improve it constantly.
+You may choose to use it as a template or reference for your own deployment,
+but *we make no claim that it is suitable for your purposes*.
+Feel free change things to suit your needs or preferences.
 
-You don't have to use the tools we use in the templates. You can use whatever tools you prefer.
-
-If you find the cloud deployment templates for nodes helpful, then you may also be interested in our scripts for :doc:`deploying a testing cluster on AWS <../clusters-feds/aws-testing-cluster>` (documented in the Clusters section).
 
 .. toctree::
    :maxdepth: 1
 
-   template-terraform-aws
-   template-ansible
-   azure-quickstart-template
    template-kubernetes-azure
    node-on-kubernetes
    add-node-on-kubernetes
diff --git a/docs/server/source/index.rst b/docs/server/source/index.rst
index bf45aca0..0dee9174 100644
--- a/docs/server/source/index.rst
+++ b/docs/server/source/index.rst
@@ -7,14 +7,14 @@ BigchainDB Server Documentation
    ← Back to All BigchainDB Docs <https://docs.bigchaindb.com/en/latest/index.html>
    introduction
    quickstart
-   cloud-deployment-templates/index
    production-nodes/index
+   clusters-feds/index
+   cloud-deployment-templates/index
    dev-and-test/index
    server-reference/index
    http-client-server-api
    websocket-event-stream-api
    drivers-clients/index
-   clusters-feds/index
    data-models/index
    schema/transaction
    schema/vote

From cab2ea11abe4f4e0455667b203f9d4216d79a56d Mon Sep 17 00:00:00 2001
From: Troy McConaghy <troy@bigchaindb.com>
Date: Thu, 18 May 2017 14:39:23 +0200
Subject: [PATCH 15/26] use default mongodb replica set name when run mongod
 for tests

---
 tests/README.md | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/tests/README.md b/tests/README.md
index d0e2da52..e6de82c9 100644
--- a/tests/README.md
+++ b/tests/README.md
@@ -27,8 +27,7 @@ BigchainDB from source. The [`CONTRIBUTING.md` file](../CONTRIBUTING.md) has
 instructions for how to do that.
 
 Next, make sure you have RethinkDB or MongoDB running in the background. You
-can run RethinkDB using `rethinkdb --daemon` or MongoDB using `mongod
---replSet=rs0`.
+can run RethinkDB using `rethinkdb --daemon` or MongoDB using `mongod --replSet=bigchain-rs`.
 
 The `pytest` command has many options. If you want to learn about all the
 things you can do with pytest, see [the pytest

From 780a9c9bf5bd7390c530124e89f2ba73f6ed743d Mon Sep 17 00:00:00 2001
From: Troy McConaghy <troy@bigchaindb.com>
Date: Thu, 18 May 2017 14:41:16 +0200
Subject: [PATCH 16/26] Quickstart docs: tell them to run MongoDB using 'sudo
 mongod ...'

---
 docs/server/source/quickstart.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/server/source/quickstart.md b/docs/server/source/quickstart.md
index 2eae07f0..5c2b0500 100644
--- a/docs/server/source/quickstart.md
+++ b/docs/server/source/quickstart.md
@@ -8,7 +8,7 @@ A. Install MongoDB as the database backend. (There are other options but you can
 
 B. Run MongoDB. Open a Terminal and run the command:
 ```text
-$ mongod --replSet=bigchain-rs
+$ sudo mongod --replSet=bigchain-rs
 ```
 
 C. Ubuntu 16.04 already has Python 3.5, so you don't need to install it, but you do need to install some other things:

From 69cafee156d088ef4de0fca0fc4dfbc53ecb3678 Mon Sep 17 00:00:00 2001
From: Troy McConaghy <troy@bigchaindb.com>
Date: Wed, 17 May 2017 15:20:20 +0200
Subject: [PATCH 17/26] Add steps to Release_Process.md, to update Docker image
 version for k8s

---
 Release_Process.md | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/Release_Process.md b/Release_Process.md
index e4a988a1..be4c448a 100644
--- a/Release_Process.md
+++ b/Release_Process.md
@@ -10,6 +10,7 @@ that [major version 0.x does not export a stable API](http://semver.org/#spec-it
 A minor release is preceeded by a feature freeze and created from the 'master' branch. This is a summary of the steps we go through to release a new minor version of BigchainDB Server.
 
 1. Update the `CHANGELOG.md` file in master
+1. In `k8s/bigchaindb/bigchaindb-dep.yaml`, find the line of the form `image: bigchaindb/bigchaindb:0.8.1` and change the version number to the new version number, e.g. `0.9.0`. (This is the Docker image that Kubernetes should pull from Docker Hub.) Commit that change to master
 1. Create and checkout a new branch for the minor release, named after the minor version, without a preceeding 'v', e.g. `git checkout -b 0.9` (*not* 0.9.0, this new branch will be for e.g. 0.9.0, 0.9.1, 0.9.2, etc. each of which will be identified by a tagged commit)
 1. In `bigchaindb/version.py`, update `__version__` and `__short_version__`, e.g. to `0.9` and `0.9.0` (with no `.dev` on the end)
 1. Commit that change, and push the new branch to GitHub
@@ -26,8 +27,11 @@ A patch release is similar to a minor release, but piggybacks on an existing min
 1. Check out the minor release branch, e.g. `0.9`
 1. Apply the changes you want, e.g. using `git cherry-pick`.
 1. Update the `CHANGELOG.md` file
-1. Increment the patch version in `bigchaindb/version.py`, e.g. "0.9.1"
-1. Commit that change, and push the updated branch to GitHub
+1. Increment the patch version in `bigchaindb/version.py`, e.g. `0.9.1`
+1. Commit that change
+1. In `k8s/bigchaindb/bigchaindb-dep.yaml`, find the line of the form `image: bigchaindb/bigchaindb:0.9.0` and change the version number to the new version number, e.g. `0.9.1`. (This is the Docker image that Kubernetes should pull from Docker Hub.)
+1. Commit that change
+1. Push the updated minor release branch to GitHub
 1. Follow steps outlined in [Common Steps](#common-steps)
 1. Cherry-pick the `CHANGELOG.md` update commit (made above) to the `master` branch
 

From c6133c827d51edb5c10a8577b15b37ecf982b5d2 Mon Sep 17 00:00:00 2001
From: Troy McConaghy <troy@bigchaindb.com>
Date: Wed, 17 May 2017 14:29:37 +0200
Subject: [PATCH 18/26] docs: updated link to JS/nodejs driver

---
 docs/server/source/drivers-clients/index.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/server/source/drivers-clients/index.rst b/docs/server/source/drivers-clients/index.rst
index 0bfde7ad..ef749d55 100644
--- a/docs/server/source/drivers-clients/index.rst
+++ b/docs/server/source/drivers-clients/index.rst
@@ -20,7 +20,7 @@ Community-Driven Libraries and Tools
    Some of these projects are a work in progress,
    but may still be useful.
 
-* `Javascript transaction builder <https://github.com/sohkai/js-bigchaindb-quickstart>`_
+* `JavaScript / Node.js driver <https://github.com/bigchaindb/js-bigchaindb-driver>`_
 * `Haskell transaction builder <https://github.com/bigchaindb/bigchaindb-hs>`_
 * `Go driver <https://github.com/zbo14/envoke/blob/master/bigchain/bigchain.go>`_
 * `Java driver <https://github.com/mgrand/bigchaindb-java-driver>`_

From ba40034362df9f2910a8c3755e05334ef3339dc8 Mon Sep 17 00:00:00 2001
From: Sylvain Bellemare <sylvain@ascribe.io>
Date: Tue, 16 May 2017 12:07:04 +0200
Subject: [PATCH 19/26] Update changelog for v0.10.2

---
 CHANGELOG.md | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3db903e3..4bfbd8dd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,20 @@ For reference, the possible headings are:
 * **External Contributors** to list contributors outside of BigchainDB GmbH.
 * **Notes**
 
+## [0.10.2] - 2017-05-16
+Tag name: v0.10.2
+
+## Added
+* Add Cross Origin Resource Sharing (CORS) support for the HTTP API. 
+ [Commit 6cb7596](https://github.com/bigchaindb/bigchaindb/commit/6cb75960b05403c77bdae0fd327612482589efcb)
+
+## Fixed
+* Fixed `streams_v1` API link in response to `GET /api/v1`.
+ [Pull Request #1466](https://github.com/bigchaindb/bigchaindb/pull/1466)
+* Fixed mismatch between docs and implementation for `GET /blocks?status=`
+  endpoint. The `status` query parameter is now case insensitive.
+ [Pull Request #1464](https://github.com/bigchaindb/bigchaindb/pull/1464)
+
 ## [0.10.1] - 2017-04-19
 Tag name: v0.10.1
 

From 710fde686d3ecaf186c95785a29f952613a54f0a Mon Sep 17 00:00:00 2001
From: Krish <krish7919@users.noreply.github.com>
Date: Wed, 17 May 2017 10:12:56 +0200
Subject: [PATCH 20/26] Update bigchaindb default deployment version

Updated to the latest release, version 0.10.2.
---
 k8s/bigchaindb/bigchaindb-dep.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/k8s/bigchaindb/bigchaindb-dep.yaml b/k8s/bigchaindb/bigchaindb-dep.yaml
index 1e8ca56d..140ef50e 100644
--- a/k8s/bigchaindb/bigchaindb-dep.yaml
+++ b/k8s/bigchaindb/bigchaindb-dep.yaml
@@ -18,7 +18,7 @@ spec:
       terminationGracePeriodSeconds: 10
       containers:
       - name: bigchaindb
-        image: bigchaindb/bigchaindb:0.10.1
+        image: bigchaindb/bigchaindb:0.10.2
         imagePullPolicy: IfNotPresent
         args:
         - start

From 6900e864584f89dd8f07132a45f801b16be4bc10 Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Wed, 24 May 2017 11:38:15 +0200
Subject: [PATCH 21/26] Filter out assets from invalid transactions

- Created docstrings
- Created tests
- Raise an exception when trying to use text search with RethinkDB.
---
 bigchaindb/backend/mongodb/query.py |  2 +-
 bigchaindb/backend/query.py         | 28 ++++++++--
 bigchaindb/core.py                  | 11 ++++
 tests/db/test_bigchain_api.py       | 83 +++++++++++++++++++++++++++++
 4 files changed, 120 insertions(+), 4 deletions(-)

diff --git a/bigchaindb/backend/mongodb/query.py b/bigchaindb/backend/mongodb/query.py
index 3d989a3d..ffba23be 100644
--- a/bigchaindb/backend/mongodb/query.py
+++ b/bigchaindb/backend/mongodb/query.py
@@ -330,7 +330,7 @@ def get_unvoted_blocks(conn, node_pubkey):
 
 
 @register_query(MongoDBConnection)
-def text_search(conn, search, language='english', case_sensitive=False,
+def text_search(conn, search, *, language='english', case_sensitive=False,
                 diacritic_sensitive=False, text_score=False, limit=0):
     cursor = conn.run(
         conn.collection('assets')
diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 705b0306..83179c2d 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -2,6 +2,8 @@
 
 from functools import singledispatch
 
+from bigchaindb.backend.exceptions import OperationError
+
 
 @singledispatch
 def write_transaction(connection, signed_transaction):
@@ -328,8 +330,28 @@ def get_txids_filtered(connection, asset_id, operation=None):
 
 
 @singledispatch
-def text_search(conn, search, language='english', case_sensitive=False,
+def text_search(conn, search, *, language='english', case_sensitive=False,
                 diacritic_sensitive=False, text_score=False, limit=0):
-    # TODO: docstring
+    """Return all the assets that match the text search.
 
-    raise NotImplementedError
+    The results are sorted by text score.
+
+    Args:
+        search (str): Text search string to query the text index
+        language (str, optional): The language for the search and the rules for
+            stemmer and tokenizer. If the language is `None` text search uses
+            simple tokenization and no stemming.
+        case_sensitive (bool, optional): Enable or disable case sensitive
+            search.
+        diacritic_sensitive (bool, optional): Enable or disable case sensitive
+            diacritic search.
+        text_score (bool, optional): If `True` returns the text score with
+            each document.
+        limit (int, optional): Limit the number of returned documents.
+
+    Returns:
+        :obj:`list` of :obj:`dict`: a list of assets
+    """
+
+    raise OperationError('This query is only supported when running '
+                         'BigchainDB with MongoDB as the backend.')
diff --git a/bigchaindb/core.py b/bigchaindb/core.py
index 1cd21222..42589b36 100644
--- a/bigchaindb/core.py
+++ b/bigchaindb/core.py
@@ -662,3 +662,14 @@ class Bigchain(object):
                 the database.
         """
         return backend.query.write_assets(self.connection, assets)
+
+    def text_search(self, search, *, limit=0):
+        assets = backend.query.text_search(self.connection, search, limit=limit)
+
+        # TODO: This is not efficient. There may be a more efficient way to
+        #       query by storing block ids with the assets and using fastquery.
+        #       See https://github.com/bigchaindb/bigchaindb/issues/1496
+        for asset in assets:
+            tx, status = self.get_transaction(asset['id'], True)
+            if status == self.TX_VALID:
+                yield asset
diff --git a/tests/db/test_bigchain_api.py b/tests/db/test_bigchain_api.py
index 5960f171..339c565d 100644
--- a/tests/db/test_bigchain_api.py
+++ b/tests/db/test_bigchain_api.py
@@ -213,6 +213,89 @@ class TestBigchainApi(object):
         assert b.get_transaction(tx1.id) is None
         assert b.get_transaction(tx2.id) == tx2
 
+    @pytest.mark.genesis
+    def test_text_search(self, b):
+        from bigchaindb.models import Transaction
+        from bigchaindb.backend.exceptions import OperationError
+        from bigchaindb.backend.mongodb.connection import MongoDBConnection
+
+        # define the assets
+        asset1 = {'msg': 'BigchainDB 1'}
+        asset2 = {'msg': 'BigchainDB 2'}
+        asset3 = {'msg': 'BigchainDB 3'}
+
+        # create the transactions
+        tx1 = Transaction.create([b.me], [([b.me], 1)],
+                                 asset=asset1).sign([b.me_private])
+        tx2 = Transaction.create([b.me], [([b.me], 1)],
+                                 asset=asset2).sign([b.me_private])
+        tx3 = Transaction.create([b.me], [([b.me], 1)],
+                                 asset=asset3).sign([b.me_private])
+
+        # create the block
+        block = b.create_block([tx1, tx2, tx3])
+        b.write_block(block)
+
+        # vote valid
+        vote = b.vote(block.id, b.get_last_voted_block().id, True)
+        b.write_vote(vote)
+
+        # get the assets through text search
+        # this query only works with MongoDB
+        try:
+            assets = list(b.text_search('bigchaindb'))
+        except OperationError as exc:
+            assert not isinstance(b.connection, MongoDBConnection)
+            return
+
+        assert len(assets) == 3
+
+    @pytest.mark.genesis
+    def test_text_search_returns_valid_only(self, monkeypatch, b):
+        from bigchaindb.models import Transaction
+        from bigchaindb.backend.exceptions import OperationError
+        from bigchaindb.backend.mongodb.connection import MongoDBConnection
+
+        asset_valid = {'msg': 'Hello BigchainDB!'}
+        asset_invalid = {'msg': 'Goodbye BigchainDB!'}
+
+        monkeypatch.setattr('time.time', lambda: 1000000000)
+        tx1 = Transaction.create([b.me], [([b.me], 1)],
+                                 asset=asset_valid)
+        tx1 = tx1.sign([b.me_private])
+        block1 = b.create_block([tx1])
+        b.write_block(block1)
+
+        monkeypatch.setattr('time.time', lambda: 1000000020)
+        tx2 = Transaction.create([b.me], [([b.me], 1)],
+                                 asset=asset_invalid)
+        tx2 = tx2.sign([b.me_private])
+        block2 = b.create_block([tx2])
+        b.write_block(block2)
+
+        # vote the first block valid
+        vote = b.vote(block1.id, b.get_last_voted_block().id, True)
+        b.write_vote(vote)
+
+        # vote the second block invalid
+        vote = b.vote(block2.id, b.get_last_voted_block().id, False)
+        b.write_vote(vote)
+
+        # get assets with text search
+        try:
+            assets = list(b.text_search('bigchaindb'))
+        except OperationError:
+            assert not isinstance(b.connection, MongoDBConnection)
+            return
+
+        # should only return one asset
+        assert len(assets) == 1
+        # should return the asset created by tx1
+        assert assets[0] == {
+            'data': {'msg': 'Hello BigchainDB!'},
+            'id': tx1.id
+        }
+
     @pytest.mark.usefixtures('inputs')
     def test_write_transaction(self, b, user_pk, user_sk):
         from bigchaindb import Bigchain

From 56379e9bec27e0a9e98ebc564c80f61e8c36c3c7 Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Wed, 24 May 2017 12:11:40 +0200
Subject: [PATCH 22/26] fix pep8 issue

---
 tests/backend/mongodb/test_queries.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/backend/mongodb/test_queries.py b/tests/backend/mongodb/test_queries.py
index a536525b..897a0f06 100644
--- a/tests/backend/mongodb/test_queries.py
+++ b/tests/backend/mongodb/test_queries.py
@@ -596,4 +596,4 @@ def test_text_search():
     assert list(query.text_search(conn, 'coffee', limit=2)) == [
         {'id': 1, 'subject': 'coffee', 'author': 'xyz', 'views': 50},
         {'id': 2, 'subject': 'Coffee Shopping', 'author': 'efg', 'views': 5},
-    ]
\ No newline at end of file
+    ]

From cda8259e5704b0d03568d602d7f039c5219bf518 Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Wed, 24 May 2017 12:38:34 +0200
Subject: [PATCH 23/26] Fixed typos

---
 bigchaindb/backend/query.py | 4 ++--
 bigchaindb/core.py          | 2 +-
 bigchaindb/models.py        | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 8245fb3d..9b2197a5 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -229,7 +229,7 @@ def get_assets(connection, asset_ids):
     """Get a list of assets from the assets table.
 
     Args:
-        asset_ids (list): a of list of ids for the assets to be retrieved from
+        asset_ids (list): a list of ids for the assets to be retrieved from
         the database.
 
     Returns:
@@ -293,7 +293,7 @@ def get_last_voted_block_id(connection, node_pubkey):
         node_pubkey (str): base58 encoded public key.
 
     Returns:
-        The last block id the node has voted on. If the node didn't cast
+        The id of the last block the node has voted on. If the node didn't cast
         any vote then the genesis block id is returned.
     """
 
diff --git a/bigchaindb/core.py b/bigchaindb/core.py
index 1cd21222..b2c8d398 100644
--- a/bigchaindb/core.py
+++ b/bigchaindb/core.py
@@ -648,7 +648,7 @@ class Bigchain(object):
             asset_ids (:obj:`list` of :obj:`str`): A list of asset_ids to
                 retrieve from the database.
 
-        Returs:
+        Returns:
             list: The list of assets returned from the database.
         """
         return backend.query.get_assets(self.connection, asset_ids)
diff --git a/bigchaindb/models.py b/bigchaindb/models.py
index c77c3338..58743939 100644
--- a/bigchaindb/models.py
+++ b/bigchaindb/models.py
@@ -106,7 +106,7 @@ class Transaction(Transaction):
         if tx_dict['operation'] in [Transaction.CREATE, Transaction.GENESIS]:
             # TODO: Maybe replace this call to a call to get_asset_by_id
             asset = list(bigchain.get_assets([tx_dict['id']]))[0]
-            asset.pop('id')
+            del asset['id']
             tx_dict.update({'asset': asset})
 
         return cls.from_dict(tx_dict)

From ae564974561e4de29d8469252aff69ef073432bd Mon Sep 17 00:00:00 2001
From: Leo Arias <leo.arias@canonical.com>
Date: Fri, 19 May 2017 15:37:38 -0600
Subject: [PATCH 24/26] set the version of the snap using git tags

closes #1436
---
 snap/snapcraft.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/snap/snapcraft.yaml b/snap/snapcraft.yaml
index aa3a9bca..4fe5618f 100644
--- a/snap/snapcraft.yaml
+++ b/snap/snapcraft.yaml
@@ -1,5 +1,5 @@
 name: bigchaindb
-version: master
+version: git
 summary: a scalable blockchain database
 description: |
   With high throughput, sub-second latency and powerful functionality to

From e9979dda85732eb3134fd0a670c9a92ed3c29e25 Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Wed, 24 May 2017 17:05:43 +0200
Subject: [PATCH 25/26] fixed typos

---
 bigchaindb/models.py      | 13 ++++++-------
 tests/test_block_model.py |  2 +-
 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/bigchaindb/models.py b/bigchaindb/models.py
index 58743939..8ca79b67 100644
--- a/bigchaindb/models.py
+++ b/bigchaindb/models.py
@@ -351,7 +351,7 @@ class Block(object):
 
     def decouple_assets(self):
         """
-        Extracts the assets from the `CREATE` transactions in the block.
+        Extracts the assets from the ``CREATE`` transactions in the block.
 
         Returns:
             tuple: (assets, block) with the assets being a list of dicts and
@@ -372,9 +372,9 @@ class Block(object):
     @staticmethod
     def couple_assets(block_dict, assets):
         """
-        Give a block_dict with not assets (as returned from a database call)
-        and a list of assets, reconstruct the original block by puting the
-        assets back into the `CREATE` transactions in the block.
+        Given a block_dict with no assets (as returned from a database call)
+        and a list of assets, reconstruct the original block by putting the
+        assets back into the ``CREATE`` transactions in the block.
 
         Args:
             block_dict (:obj:`dict`): The block dict as returned from a
@@ -391,15 +391,14 @@ class Block(object):
         for transaction in block_dict['block']['transactions']:
             if transaction['operation'] in [Transaction.CREATE,
                                             Transaction.GENESIS]:
-                transaction.update({'asset': assets.get(transaction['id'],
-                                                        None)})
+                transaction.update({'asset': assets.get(transaction['id'])})
         return block_dict
 
     @staticmethod
     def get_asset_ids(block_dict):
         """
         Given a block_dict return all the asset_ids for that block (the txid
-        of CREATE transactions). Usefull to know which assets to retrieve
+        of CREATE transactions). Useful to know which assets to retrieve
         from the database to reconstruct the block.
 
         Args:
diff --git a/tests/test_block_model.py b/tests/test_block_model.py
index 0824c40f..6e14d293 100644
--- a/tests/test_block_model.py
+++ b/tests/test_block_model.py
@@ -220,7 +220,7 @@ class TestBlockModel(object):
         block_dict_reconstructed = Block.couple_assets(block_dict,
                                                        assets_from_block)
 
-        # check that the reconstructed block is the as the original block
+        # check that the reconstructed block is the same as the original block
         assert block == Block.from_dict(block_dict_reconstructed)
 
     def test_get_asset_ids(self, b):

From 3819ae5d654968e2c6850e4407abe170ac9034a2 Mon Sep 17 00:00:00 2001
From: Rodolphe Marques <marques.rodolphe@gmail.com>
Date: Fri, 26 May 2017 10:34:58 +0200
Subject: [PATCH 26/26] Clean up code

- Fixed docstrings
---
 bigchaindb/backend/mongodb/query.py | 4 ++--
 bigchaindb/backend/query.py         | 6 ++++--
 tests/db/test_bigchain_api.py       | 5 ++---
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/bigchaindb/backend/mongodb/query.py b/bigchaindb/backend/mongodb/query.py
index 9b25c0fc..eaef721d 100644
--- a/bigchaindb/backend/mongodb/query.py
+++ b/bigchaindb/backend/mongodb/query.py
@@ -371,8 +371,8 @@ def text_search(conn, search, *, language='english', case_sensitive=False,
 
     if text_score:
         return cursor
-    else:
-        return (_remove_text_score(asset) for asset in cursor)
+
+    return (_remove_text_score(asset) for asset in cursor)
 
 
 def _remove_text_score(asset):
diff --git a/bigchaindb/backend/query.py b/bigchaindb/backend/query.py
index 07fd3e4c..74879cef 100644
--- a/bigchaindb/backend/query.py
+++ b/bigchaindb/backend/query.py
@@ -363,17 +363,19 @@ def text_search(conn, search, *, language='english', case_sensitive=False,
     """Return all the assets that match the text search.
 
     The results are sorted by text score.
+    For more information about the behavior of text search on MongoDB see
+    https://docs.mongodb.com/manual/reference/operator/query/text/#behavior
 
     Args:
         search (str): Text search string to query the text index
         language (str, optional): The language for the search and the rules for
-            stemmer and tokenizer. If the language is `None` text search uses
+            stemmer and tokenizer. If the language is ``None`` text search uses
             simple tokenization and no stemming.
         case_sensitive (bool, optional): Enable or disable case sensitive
             search.
         diacritic_sensitive (bool, optional): Enable or disable case sensitive
             diacritic search.
-        text_score (bool, optional): If `True` returns the text score with
+        text_score (bool, optional): If ``True`` returns the text score with
             each document.
         limit (int, optional): Limit the number of returned documents.
 
diff --git a/tests/db/test_bigchain_api.py b/tests/db/test_bigchain_api.py
index feb24e9c..05b07bf6 100644
--- a/tests/db/test_bigchain_api.py
+++ b/tests/db/test_bigchain_api.py
@@ -246,9 +246,8 @@ class TestBigchainApi(object):
             assets = list(b.text_search('bigchaindb'))
         except OperationError as exc:
             assert not isinstance(b.connection, MongoDBConnection)
-            return
-
-        assert len(assets) == 3
+        else:
+            assert len(assets) == 3
 
     @pytest.mark.genesis
     def test_text_search_returns_valid_only(self, monkeypatch, b):