Make shutdown timings configurable.

docs/history.rst

@@ -5,6 +5,7 @@ Release History
 
 `Next Release`_
 ---------------
+- Make shutdown timings configurable.
 
 `2.0.1`_ (5 Mar 2019)
 ----------------------

sprockets/http/app.py

@@ -8,11 +8,12 @@ from tornado import concurrent, web
 class _ShutdownHandler:
     """Keeps track of the application state during shutdown."""
 
-    def __init__(self, io_loop):
+    def __init__(self, io_loop, shutdown_limit, wait_timeout):
         self.io_loop = io_loop
         self.logger = logging.getLogger(self.__class__.__name__)
         self.pending_callbacks = 0
-        self.shutdown_limit = 5
+        self.shutdown_limit = shutdown_limit
+        self.wait_timeout = wait_timeout
         self.__deadline = None
 
     def add_future(self, future):
@@ -42,7 +43,7 @@ class _ShutdownHandler:
     def _maybe_stop(self):
         now = self.io_loop.time()
         if now < self.__deadline and asyncio.Task.all_tasks():
-            self.io_loop.add_timeout(now + 1, self._maybe_stop)
+            self.io_loop.add_timeout(now + self.wait_timeout, self._maybe_stop)
         else:
             self.io_loop.stop()
             self.logger.info('stopped IOLoop')
@@ -103,20 +104,24 @@ class CallbackManager:
         for callback in self.on_start_callbacks:
             io_loop.spawn_callback(callback, self.tornado_application, io_loop)
 
-    def stop(self, io_loop):
+    def stop(self, io_loop, shutdown_limit=5.0, wait_timeout=1.0):
         """
         Asynchronously stop the application.
 
         :param tornado.ioloop.IOLoop io_loop: loop to run until all
             callbacks, timeouts, and queued calls are complete
+        :param float shutdown_limit: maximum number of seconds to wait
+            before terminating
+        :param float wait_timeout: number of seconds to wait between checks
+            for pending callbacks & timers
 
         Call this method to start the application shutdown process.
         The IOLoop will be stopped once the application is completely
-        shut down.
+        shut down or after `shutdown_limit` seconds.
 
         """
         running_async = False
-        shutdown = _ShutdownHandler(io_loop)
+        shutdown = _ShutdownHandler(io_loop, shutdown_limit, wait_timeout)
         for callback in self.on_shutdown_callbacks:
             try:
                 maybe_future = callback(self.tornado_application)

sprockets/http/runner.py

@@ -55,6 +55,8 @@ class Runner:
             app, before_run, on_start, shutdown)
         self.logger = logging.getLogger('Runner')
         self.server = None
+        self.shutdown_limit = 5.0
+        self.wait_timeout = 1.0
 
     def start_server(self, port_number, number_of_procs=0):
         """
@@ -142,7 +144,8 @@ class Runner:
         self.stop_server()
 
         # Start the application shutdown process
-        self.application.stop(ioloop.IOLoop.instance())
+        self.application.stop(ioloop.IOLoop.instance(), self.shutdown_limit,
+                              self.wait_timeout)
 
 
 class RunCommand(cmd.Command):

tests.py

@@ -448,6 +448,7 @@ class RunnerTests(MockHelper, unittest.TestCase):
         self.io_loop._timeouts = [mock.Mock()]
         runner = sprockets.http.runner.Runner(self.application)
         runner.shutdown_limit = 0.25
+        runner.wait_timeout = 0.05
         runner.run(8000)
         runner._shutdown()
         self.io_loop.stop.assert_called_once_with()