Raise RuntimeError if starting the scheduler under uWSGI without threads

apscheduler/schedulers/base.py

@@ -127,11 +127,14 @@ def start(self, paused=False):
 
         :param bool paused: if ``True``, don't start job processing until :meth:`resume` is called
         :raises SchedulerAlreadyRunningError: if the scheduler is already running
+        :raises RuntimeError: if running under uWSGI with threads disabled
 
         """
         if self.state != STATE_STOPPED:
             raise SchedulerAlreadyRunningError
 
+        self._check_uwsgi()
+
         with self._executors_lock:
             # Create a default executor if nothing else is configured
             if 'default' not in self._executors:
@@ -826,6 +829,14 @@ def _dispatch_event(self, event):
                 except BaseException:
                     self._logger.exception('Error notifying listener')
 
+    def _check_uwsgi(self):
+        """Check if we're running under uWSGI with threads disabled."""
+        uwsgi_module = sys.modules.get('uwsgi')
+        if not getattr(uwsgi_module, 'has_threads', True):
+            raise RuntimeError('The scheduler seems to be running under uWSGI, but threads have '
+                               'been disabled. You must run uWSGI with the --enable-threads '
+                               'option for the scheduler to work.')
+
     def _real_add_job(self, job, jobstore_alias, replace_existing):
         """
         :param Job job: the job to add

docs/versionhistory.rst

@@ -11,6 +11,8 @@ APScheduler, see the :doc:`migration section <migration>`.
   ``YourClass.methodname`` along with an explicit ``self`` argument is no longer necessary as this
   is now done automatically for you)
 * Added the FAQ section to the docs
+* Made ``BaseScheduler.start()`` raise a ``RuntimeError`` if running under uWSGI with threads
+  disabled
 
 
 3.5.1