From 47643a67c61609b47b71052ab82f0d1d23a5e483 Mon Sep 17 00:00:00 2001
From: NIC619 <twedusuck@gmail.com>
Date: Tue, 6 Aug 2019 12:32:18 +0800
Subject: [PATCH] Apply PR feedback

---
 libp2p/pubsub/pubsub.py     | 30 ++++++++++++++++++------------
 libp2p/pubsub/validators.py |  2 +-
 2 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/libp2p/pubsub/pubsub.py b/libp2p/pubsub/pubsub.py
index 0dcee67..dd51be2 100644
--- a/libp2p/pubsub/pubsub.py
+++ b/libp2p/pubsub/pubsub.py
@@ -1,7 +1,7 @@
 import asyncio
-from collections import namedtuple
+import logging
 import time
-from typing import TYPE_CHECKING, Any, Awaitable, Callable, Dict, Iterable, List, Tuple, Union
+from typing import TYPE_CHECKING, Any, Awaitable, Callable, Dict, List, NamedTuple, Tuple, Union
 
 from lru import LRU
 
@@ -17,17 +17,20 @@ if TYPE_CHECKING:
     from .pubsub_router_interface import IPubsubRouter
 
 
+log = logging.getLogger(__name__)
+
+
 def get_msg_id(msg: rpc_pb2.Message) -> Tuple[bytes, bytes]:
     # NOTE: `string(from, seqno)` in Go
     return (msg.seqno, msg.from_id)
 
 
-TopicValidator = namedtuple("TopicValidator", ["validator", "is_async"])
-
-
 ValidatorFn = Union[Callable[[ID, rpc_pb2.Message], bool], Awaitable[bool]]
 
 
+TopicValidator = NamedTuple("TopicValidator", (("validator", ValidatorFn), ("is_async", bool)))
+
+
 class Pubsub:
 
     host: IHost
@@ -181,14 +184,14 @@ class Pubsub:
         if topic in self.topic_validators:
             del self.topic_validators[topic]
 
-    def get_msg_validators(self, msg: rpc_pb2.Message) -> Iterable[TopicValidator]:
+    def get_msg_validators(self, msg: rpc_pb2.Message) -> Tuple[TopicValidator, ...]:
         """
         Get all validators corresponding to the topics in the message.
         :param msg: the message published to the topic
         """
-        for topic in msg.topicIDs:
-            if topic in self.topic_validators:
-                yield self.topic_validators[topic]
+        return (
+            self.topic_validators[topic] for topic in msg.topicIDs if topic in self.topic_validators
+        )
 
     async def stream_handler(self, stream: INetStream) -> None:
         """
@@ -399,15 +402,18 @@ class Pubsub:
 
         # TODO: Check if signing is required and if so signature should be attached.
 
+        # If the message is processed before, return(i.e., don't further process the message).
         if self._is_msg_seen(msg):
             return
 
         # TODO: - Validate the message. If failed, reject it.
         # Validate the signature of the message
         # FIXME: `signature_validator` is currently a stub.
-        if not signature_validator(msg.key, msg.SerializeToString()):
+        if not signature_validator(msg.key, msg.SerializeToString(), msg.singature):
+            log.debug(f"Signature validation failed for msg={msg}")
             return
-        # Validate the message with registered topic validators
+        # Validate the message with registered topic validators.
+        # If the validation failed, return(i.e., don't further process the message).
         is_validation_passed = await self.validate_msg(msg_forwarder, msg)
         if not is_validation_passed:
             return
@@ -436,4 +442,4 @@ class Pubsub:
     def _is_subscribed_to_msg(self, msg: rpc_pb2.Message) -> bool:
         if not self.my_topics:
             return False
-        return any([topic in self.my_topics for topic in msg.topicIDs])
+        return any(topic in self.my_topics for topic in msg.topicIDs)
diff --git a/libp2p/pubsub/validators.py b/libp2p/pubsub/validators.py
index e575980..4d99ede 100644
--- a/libp2p/pubsub/validators.py
+++ b/libp2p/pubsub/validators.py
@@ -1,5 +1,5 @@
 # FIXME: Replace the type of `pubkey` with a custom type `Pubkey`
-def signature_validator(pubkey: bytes, msg: bytes) -> bool:
+def signature_validator(pubkey: bytes, msg: bytes, sig: bytes) -> bool:
     """
     Verify the message against the given public key.
     :param pubkey: the public key which signs the message.