Replace sync_to_async with database_sync_to_async

NOTICE

@@ -0,0 +1 @@
+Some parts of Nautobot-App-Chatops are based upon `channels`, licensed under BSD-3-Clause by Django Software Foundation.

changes/355.fixed

@@ -0,0 +1 @@
+Fixed "Server has gone away" error in Slack Socket Mode.

nautobot_chatops/sockets/slack.py

@@ -4,15 +4,14 @@
 import json
 import shlex
 
-from asgiref.sync import sync_to_async
 from django.conf import settings
 from slack_sdk.socket_mode.aiohttp import SocketModeClient
 from slack_sdk.socket_mode.request import SocketModeRequest
 from slack_sdk.socket_mode.response import SocketModeResponse
 from slack_sdk.web.async_client import AsyncWebClient
 
 from nautobot_chatops.dispatchers.slack import SlackDispatcher
-from nautobot_chatops.utils import socket_check_and_enqueue_command
+from nautobot_chatops.utils import database_sync_to_async, socket_check_and_enqueue_command
 from nautobot_chatops.workers import commands_help, get_commands_registry, parse_command_string
 
 
@@ -72,7 +71,7 @@ async def process_slash_command(client, req):
             client.logger.error("%s", err)
             return
 
-        registry = await sync_to_async(get_commands_registry)()
+        registry = await database_sync_to_async(get_commands_registry)()
 
         if command not in registry:
             SlackDispatcher(context).send_markdown(commands_help(prefix=SLASH_PREFIX))
@@ -211,7 +210,7 @@ async def process_interactive(client, req):
 
         client.logger.info(f"command: {command}, subcommand: {subcommand}, params: {params}")
 
-        registry = await sync_to_async(get_commands_registry)()
+        registry = await database_sync_to_async(get_commands_registry)()
 
         if command not in registry:
             SlackDispatcher(context).send_markdown(commands_help(prefix=SLASH_PREFIX))
@@ -242,7 +241,7 @@ async def process_mention(client, req):
             client.logger.error("%s", err)
             return
 
-        registry = await sync_to_async(get_commands_registry)()
+        registry = await database_sync_to_async(get_commands_registry)()
 
         if command not in registry:
             SlackDispatcher(context).send_markdown(commands_help(prefix=SLASH_PREFIX))

nautobot_chatops/utils.py

@@ -4,8 +4,9 @@
 import sys
 from datetime import datetime, timezone
 
-from asgiref.sync import sync_to_async
+from asgiref.sync import SyncToAsync
 from django.conf import settings
+from django.db import close_old_connections
 from django.db.models import Q
 from django.http import HttpResponse, JsonResponse
 from nautobot.core.celery import nautobot_task
@@ -18,6 +19,26 @@
 logger = logging.getLogger(__name__)
 
 
+class DatabaseSyncToAsync(SyncToAsync):
+    """
+    SyncToAsync version that cleans up old database connections when it exits.
+
+    Sourced from Channels, see NOTICE file for license information.
+    """
+
+    def thread_handler(self, loop, *args, **kwargs):
+        """Run the handler in a thread, closing old database connections before and after."""
+        close_old_connections()
+        try:
+            return super().thread_handler(loop, *args, **kwargs)
+        finally:
+            close_old_connections()
+
+
+# The class is TitleCased, but we want to encourage use as a callable/decorator
+database_sync_to_async = DatabaseSyncToAsync  # pylint: disable=invalid-name
+
+
 def get_app_config_part(prefix: str) -> dict:
     """Get part of the app config.
 
@@ -113,7 +134,7 @@ def create_command_log(dispatcher, registry, command, subcommand, params=()):
     )
 
 
-@sync_to_async
+@database_sync_to_async
 def socket_check_and_enqueue_command(*args, **kwargs):
     """Calls check_and_enqueue_command() when in Socket mode."""
     return check_and_enqueue_command(*args, **kwargs)