Fix issue #13

django_apscheduler/jobstores.py

@@ -10,7 +10,7 @@
 
 from django.core.exceptions import ObjectDoesNotExist
 from django.db import connections
-from django.db.utils import OperationalError
+from django.db.utils import OperationalError, ProgrammingError
 
 from django_apscheduler.models import DjangoJob
 from django_apscheduler.result_storage import DjangoResultStorage
@@ -25,7 +25,7 @@ def ignore_database_error(func):
     def inner(*a, **k):
         try:
             return func(*a, **k)
-        except OperationalError as e:
+        except (OperationalError, ProgrammingError) as e:
             warnings.warn(
                 "Got OperationalError: {}. "
                 "Please, check that you have migrated the database via python manage.py migrate".format(e),
@@ -209,6 +209,24 @@ def register_events(scheduler, result_storage=None):
 
 
 def register_job(scheduler, *a, **k):
+    """
+
+    Helper decorator for job registration.
+    Automatically fills id parameter to prevent jobs duplication.
+    See this comment for explanation: https://github.com/jarekwg/django-apscheduler/pull/9#issuecomment-342074372
+
+    Usage example::
+
+        @register_job(scheduler, "interval", seconds=1)
+        def test_job():
+            time.sleep(4)
+            print("I'm a test job!")
+
+    :param scheduler: Scheduler instance
+    :type scheduler: BaseScheduler
+
+    :param a, k: Params, will be passed to scheduler.add_job method. See :func:`BaseScheduler.add_job`
+    """
     # type: (BaseScheduler)->callable
 
     def inner(func):

django_apscheduler/models.py

@@ -1,6 +1,38 @@
 # coding=utf-8
-from django.db import models
+from django.db import models, connection
 from django.utils.safestring import mark_safe
+import time
+import logging
+
+LOGGER = logging.getLogger("django_apscheduler")
+
+class DjangoJobManager(models.Manager):
+    """
+    This manager pings database each request after 30s IDLE to prevent MysqlGoneAway error
+    """
+    _last_ping = 0
+    _ping_interval = 30
+
+    def get_queryset(self):
+        self.__ping()
+        return super(DjangoJobManager, self).get_queryset()
+
+    def __ping(self):
+        if time.time() - self._last_ping < self._ping_interval:
+            return
+
+        try:
+            with connection.cursor() as c:
+                c.execute("SELECT 1")
+        except Exception as e:
+            self.__reconnect()
+
+        self._last_ping = time.time()
+
+    def __reconnect(self):
+        LOGGER.warning("Mysql closed the connection. Perform reconnect...")
+        connection.connection.close()
+        connection.connection = None
 
 
 class DjangoJob(models.Model):
@@ -9,6 +41,8 @@ class DjangoJob(models.Model):
     # Perhaps consider using PickleField down the track.
     job_state = models.BinaryField()
 
+    objects = DjangoJobManager()
+
     def __str__(self):
         status = 'next run at: %s' % self.next_run_time if self.next_run_time else 'paused'
         return '%s (%s)' % (self.name, status)

examples/example_apscheduler/example_apscheduler/jobs.py

@@ -8,9 +8,8 @@
 scheduler.add_jobstore(DjangoJobStore(), "default")
 
 
-@register_job(scheduler, "interval", seconds=1)
+@register_job(scheduler, "interval", seconds=30, replace_existing=True)
 def test_job():
-    time.sleep(4)
     print("I'm a test job!")
     # raise ValueError("Olala!")
 

examples/example_apscheduler/example_apscheduler/settings.py

@@ -76,40 +76,29 @@
 # Database
 # https://docs.djangoproject.com/en/1.11/ref/settings/#databases
 
-# DATABASES = {
-#     'default': {
-#         'ENGINE': 'django.db.backends.sqlite3',
-#         'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
-#     }
-# }
-
 DATABASES = {
     'default': {
-        'ENGINE': 'django.db.backends.mysql',
-        'NAME': 'test',
-        'USER': 'root',
-        'HOST': '127.0.0.1',
-        'PORT': 3308
+        'ENGINE': 'django.db.backends.sqlite3',
+        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
     }
 }
 
+# DATABASES = {
+#     'default': {
+#         'ENGINE': 'django.db.backends.mysql',
+#         'NAME': 'test',
+#         'USER': 'root',
+#         'HOST': '127.0.0.1',
+#         'PORT': 3308
+#     }
+# }
+
 
 # Password validation
 # https://docs.djangoproject.com/en/1.11/ref/settings/#auth-password-validators
 
 AUTH_PASSWORD_VALIDATORS = [
-    {
-        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
-    },
-    {
-        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
-    },
-    {
-        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
-    },
-    {
-        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
-    },
+
 ]
 
 

setup.py

@@ -2,7 +2,7 @@
 
 setup(
     name='django_apscheduler',
-    version='0.2.2',
+    version='0.2.3',
     description='APScheduler for Django',
     classifiers=[
         "Development Status :: 4 - Beta",

tests/compat.py

@@ -0,0 +1,7 @@
+
+try:
+    import mock
+except:
+    from unittest import mock
+
+mock_compat = mock

tests/test_jobstore.py

@@ -7,10 +7,15 @@
 from apscheduler.events import JobExecutionEvent, JobSubmissionEvent
 from apscheduler.executors.debug import DebugExecutor
 from apscheduler.schedulers.base import BaseScheduler
+from django.db import connection, transaction
+from django.db.backends.utils import CursorWrapper
+from django.db.models.sql.compiler import SQLCompiler
+from django.db.utils import OperationalError
 from pytz import utc
 
 from django_apscheduler.jobstores import DjangoJobStore, register_events, register_job
-from django_apscheduler.models import DjangoJob, DjangoJobExecution
+from django_apscheduler.models import DjangoJob, DjangoJobExecution, DjangoJobManager
+from tests.compat import mock_compat
 
 logging.basicConfig()
 
@@ -100,3 +105,22 @@ def test_job_events(db, scheduler):
     scheduler._dispatch_event(JobSubmissionEvent(32768, "job", None, [now]))
 
     assert DjangoJobExecution.objects.count() == 1
+
+@pytest.mark.test_reconnect_on_db_error
+def test_reconnect_on_db_error(transactional_db):
+
+    counter = [0]
+    def mocked_execute(self, *a, **k):
+        counter[0] += 1
+
+        if counter[0] == 1:
+            raise OperationalError()
+        else:
+            return []
+
+    with mock_compat.patch.object(CursorWrapper, "execute", mocked_execute):
+        store = DjangoJobStore()
+        DjangoJob.objects._last_ping = 0
+
+        assert store.get_due_jobs(now=datetime.datetime.now()) == []
+