Define and use lbry.utils.aclosing() in lieu of official contextlib.aclosing().

lbry/dht/node.py

@@ -5,7 +5,7 @@ import socket
 
 from prometheus_client import Gauge
 
-from lbry.utils import resolve_host
+from lbry.utils import aclosing, resolve_host
 from lbry.dht import constants
 from lbry.dht.peer import make_kademlia_peer
 from lbry.dht.protocol.distance import Distance
@@ -217,13 +217,10 @@ class Node:
                           shortlist: typing.Optional[typing.List['KademliaPeer']] = None
                           ) -> typing.List['KademliaPeer']:
         peers = []
-        node_finder = self.get_iterative_node_finder(
-                node_id, shortlist=shortlist, max_results=max_results)
-        try:
+        async with aclosing(self.get_iterative_node_finder(
+                node_id, shortlist=shortlist, max_results=max_results)) as node_finder:
             async for iteration_peers in node_finder:
                 peers.extend(iteration_peers)
-        finally:
-            await node_finder.aclose()
         distance = Distance(node_id)
         peers.sort(key=lambda peer: distance(peer.node_id))
         return peers[:count]
@@ -249,8 +246,7 @@ class Node:
 
         # prioritize peers who reply to a dht ping first
         # this minimizes attempting to make tcp connections that won't work later to dead or unreachable peers
-        value_finder = self.get_iterative_value_finder(bytes.fromhex(blob_hash))
-        try:
+        async with aclosing(self.get_iterative_value_finder(bytes.fromhex(blob_hash))) as value_finder:
             async for results in value_finder:
                 to_put = []
                 for peer in results:
@@ -280,8 +276,6 @@ class Node:
                         log.debug("skip bad peer %s:%i for %s", peer.address, peer.tcp_port, blob_hash)
                 if to_put:
                     result_queue.put_nowait(to_put)
-        finally:
-            await value_finder.aclose()
 
     def accumulate_peers(self, search_queue: asyncio.Queue,
                          peer_queue: typing.Optional[asyncio.Queue] = None

lbry/utils.py

@@ -130,6 +130,12 @@ def get_sd_hash(stream_info):
 def json_dumps_pretty(obj, **kwargs):
     return json.dumps(obj, sort_keys=True, indent=2, separators=(',', ': '), **kwargs)
 
+@contextlib.asynccontextmanager
+async def aclosing(thing):
+    try:
+        yield thing
+    finally:
+        await thing.aclose()
 
 def async_timed_cache(duration: int):
     def wrapper(func):