refactor so we can stop trapping CancelledError everywhere

lbrynet/blob_exchange/downloader.py

@@ -116,22 +116,12 @@ class BlobDownloader:
                     self.peer_queue.put_nowait(set(batch).difference(self.ignored))
                 else:
                     self.clearbanned()
-            while self.active_connections:
-                peer, task = self.active_connections.popitem()
-                if task and not task.done():
-                    task.cancel()
             blob.close()
             log.debug("downloaded %s", blob_hash[:8])
             return blob
-        except asyncio.CancelledError:
+        finally:
             while self.active_connections:
-                peer, task = self.active_connections.popitem()
-                if task and not task.done():
-                    task.cancel()
-            raise
-        except (OSError, Exception) as e:
-            log.exception(e)
-            raise e
+                self.active_connections.popitem()[1].cancel()
 
     def close(self):
         self.scores.clear()

lbrynet/dht/node.py

@@ -190,10 +190,7 @@ class Node:
 
         async def _add_hashes_from_queue():
             while True:
-                try:
                 blob_hash = await hash_queue.get()
-                except asyncio.CancelledError:
-                    break
                 peer_generator.add_generator(
                     self.get_iterative_value_finder(
                         binascii.unhexlify(blob_hash.encode()), bottom_out_limit=bottom_out_limit,
@@ -205,10 +202,6 @@ class Node:
             async with peer_generator as junction:
                 yield junction
             await peer_generator.finished.wait()
-        except asyncio.CancelledError:
-            if add_hashes_task and not (add_hashes_task.done() or add_hashes_task.cancelled()):
-                add_hashes_task.cancel()
-            raise
         finally:
             if add_hashes_task and not (add_hashes_task.done() or add_hashes_task.cancelled()):
                 add_hashes_task.cancel()
@@ -236,7 +229,6 @@ class Node:
 
     async def _accumulate_search_junction(self, search_queue: asyncio.Queue,
                                           result_queue: asyncio.Queue):
-        try:
         async with self.stream_peer_search_junction(search_queue) as search_junction:  # pylint: disable=E1701
             async for peers in search_junction:
                 if peers:
@@ -247,8 +239,6 @@ class Node:
                                 and peer.tcp_port == self.protocol.peer_port
                         )
                     ])
-        except asyncio.CancelledError:
-            return
 
     def accumulate_peers(self, search_queue: asyncio.Queue,
                          peer_queue: typing.Optional[asyncio.Queue] = None) -> typing.Tuple[

lbrynet/dht/protocol/iterative_find.py

@@ -162,8 +162,6 @@ class IterativeFinder:
     async def _send_probe(self, peer: 'KademliaPeer'):
         try:
             response = await self.send_probe(peer)
-        except asyncio.CancelledError:
-            return
         except asyncio.TimeoutError:
             self.active.discard(peer)
             return