Fix some error handling for lobby save info

This info was collected asynchronously, but the code didn't do anything
to handle the case where the socket closed before the save info was
fully collected, leading to uncaught exceptions in the logs.

diff --git a/crawl-ref/source/webserver/ws_handler.py b/crawl-ref/source/webserver/ws_handler.py
index dc09737..a5ff226 100644 (file)
--- a/crawl-ref/source/webserver/ws_handler.py
+++ b/crawl-ref/source/webserver/ws_handler.py
@@ -344,6 +344,9 @@ class CrawlWebSocket(tornado.websocket.WebSocketHandler):
         # this code would be much simpler refactored using async
         def build_callback(game_key, call, next_callback):
             def update_save_info(data, returncode):
+                global sockets
+                if not self in sockets:
+                    return
                 if returncode == 0:
                     try:
                         save_dict = json_decode(data)[load_games.game_modes[game_key]]
@@ -405,14 +408,21 @@ class CrawlWebSocket(tornado.websocket.WebSocketHandler):
         def disable_check(s):
             return s == "[slot full]"
         def send_game_links():
+            global sockets
+            if not self in sockets:
+                return # socket closed by the time this info was collected
             self.queue_message("html", id = "banner", content = banner_html)
             # TODO: dynamically send this info as it comes in, rather than
             # rendering it all at the end?
-            play_html = to_unicode(self.render_string("game_links.html",
+            try:
+                play_html = to_unicode(self.render_string("game_links.html",
                                                   games = config.games,
                                                   save_info = self.save_info,
                                                   disabled = disable_check))
-            self.send_message("set_game_links", content = play_html)
+                self.send_message("set_game_links", content = play_html)
+            except:
+                self.logger.warning("Error on send_game_links callback",
+                                                                exc_info=True)
         # if no game links at all have been sent, immediately render the
         # empty version. This is so that if the server takes a while on
         # initial connect, the player sees something immediately.