Cleanup

examples/bee_movie/msg_ordering_node.py

@@ -5,7 +5,7 @@ from tests.pubsub.utils import message_id_generator, generate_RPC_packet
 from libp2p import new_node
 from libp2p.pubsub.pubsub import Pubsub
 from libp2p.pubsub.floodsub import FloodSub
-from ordered_queue import OrderedQueue
+from .ordered_queue import OrderedQueue
 
 SUPPORTED_PUBSUB_PROTOCOLS = ["/floodsub/1.0.0"]
 BEE_MOVIE_TOPIC = "bee_movie"
@@ -17,12 +17,15 @@ class MsgOrderingNode():
         self.balances = {}
         self.next_msg_id_func = message_id_generator(0)
         self.priority_queue = OrderedQueue()
-        # self.last_word_gotten_seqno = 0
+
+        self.libp2p_node = None
+        self.floodsub = None
+        self.pubsub = None
 
     @classmethod
     async def create(cls):
         """
-        Create a new DummyAccountNode and attach a libp2p node, a floodsub, and a pubsub
+        Create a new MsgOrderingNode and attach a libp2p node, a floodsub, and a pubsub
         instance to this new node
 
         We use create as this serves as a factory function and allows us
@@ -44,7 +47,7 @@ class MsgOrderingNode():
         Handle all incoming messages on the BEE_MOVIE_TOPIC from peers
         """
         while True:
-            incoming = await self.q.get()  
+            incoming = await self.queue.get()
             seqno = int.from_bytes(incoming.seqno, byteorder='big')
             word = incoming.data.decode('utf-8')
 
@@ -55,11 +58,12 @@ class MsgOrderingNode():
         Subscribe to BEE_MOVIE_TOPIC and perform call to function that handles
         all incoming messages on said topic
         """
-        self.q = await self.pubsub.subscribe(BEE_MOVIE_TOPIC)
+        self.queue = await self.pubsub.subscribe(BEE_MOVIE_TOPIC)
 
         asyncio.ensure_future(self.handle_incoming_msgs())
 
     async def publish_bee_movie_word(self, word, msg_id=None):
+        # Publish a bee movie word to all peers
         my_id = str(self.libp2p_node.get_id())
         if msg_id is None:
             msg_id = self.next_msg_id_func()
@@ -67,7 +71,7 @@ class MsgOrderingNode():
         await self.floodsub.publish(my_id, packet.SerializeToString())
 
     async def handle_bee_movie_word(self, seqno, word):
-        # print("Handle hit for " + str(seqno) + ", " + word)
+        # Handle bee movie word received
         await self.priority_queue.put((seqno, word))
 
     async def get_next_word_in_bee_movie(self):

examples/bee_movie/ordered_queue.py

@@ -1,10 +1,13 @@
 import asyncio
 
-"""
-NOTE: ISSUE IS THAT THERE task IS BLOCKING SINCE IT IS WAITING ON SAME COROUTINE THAT 
-WE ARE RUNNING ON
-"""
 class OrderedQueue():
+    """
+    asyncio.queue wrapper that delivers messages in order of subsequent sequence numbers,
+    so if message 1 and 3 are received and the following get calls occur:
+    get(), get(), get()
+    the queue will deliver message 1, will wait until message 2 is received to deliver message 2,
+    and then deliver message 3
+    """
 
     def __init__(self):
         self.last_gotten_seqno = 0
@@ -12,6 +15,9 @@ class OrderedQueue():
         self.task = None
 
     async def put(self, item):
+        """
+        :param item: put item tuple (seqno, data) onto queue
+        """
         seqno = item[0]
         await self.queue.put(item)
         if self.last_gotten_seqno + 1 == seqno and self.task is not None:
@@ -19,15 +25,18 @@ class OrderedQueue():
             self.task.set()
 
     async def get(self):
+        """
+        Get item with last_gotten_seqno + 1 from the queue
+        :return: (seqno, data)
+        """
         if self.queue.qsize() > 0:
             front_item = await self.queue.get()
 
             if front_item[0] == self.last_gotten_seqno + 1:
                 self.last_gotten_seqno += 1
                 return front_item
-            else:
+            # Put element back as it should not be delivered yet
-                # Put element back as it should not be delivered yet
+            await self.queue.put(front_item)
-                await self.queue.put(front_item)
 
         # Wait until item with subsequent seqno is put on queue
         self.task = asyncio.Event()

examples/bee_movie/test_bee_movie.py

@@ -1,19 +1,26 @@
 import asyncio
-import multiaddr
+from threading import Thread
-import pytest
 import struct
+import pytest
 import urllib.request
 
-from threading import Thread
-from tests.utils import cleanup
-from libp2p import new_node
 from libp2p.peer.peerinfo import info_from_p2p_addr
-from libp2p.pubsub.pubsub import Pubsub
+from .msg_ordering_node import MsgOrderingNode
-from libp2p.pubsub.floodsub import FloodSub
+from tests.utils import cleanup
-from msg_ordering_node import MsgOrderingNode
 
 # pylint: disable=too-many-locals
 
+"""
+Test-cases demonstrating how to create nodes that continuously stream data
+and ensure that data is delivered to each node with pre-determined ordering.
+The ordering is such that if a peer A sends a publish 1 and 2 with seqno=1 and with seqno=2,
+respectively, even if the publish 2 (with seqno=2) reaches the peers first, it will not
+be processed until seqno=1 is received (and then publish 1 with seqno=1 must be
+processed before publish 2 with seqno=2 will be).
+
+This concept is demonstrated by streaming the script to the entire bee movie to several nodes
+"""
+
 async def connect(node1, node2):
     # node1 connects to node2
     addr = node2.get_addrs()[0]
@@ -37,7 +44,7 @@ async def perform_test(num_nodes, adjacency_map, action_func, assertion_func):
 
     # Create nodes
     dummy_nodes = []
-    for i in range(num_nodes):
+    for _ in range(num_nodes):
         dummy_nodes.append(await MsgOrderingNode.create())
 
     # Create network