Merge pull request revsys#11 from stefanfoulis/feature/celery3-support

adds support for celery3

README.md

@@ -48,7 +48,12 @@ Add required apps:
     'health_check_cache',
     'health_check_storage',
 ```
-(remember to add dependencies, e.g. djcelery - however you should have that already, if you have celery running)
+(remember to add dependencies, e.g. djcelery - however you should have that already, if you have celery running).
+You'll also have to make sure that you have a
+`result backend <http://celery.readthedocs.org/en/latest/configuration.html?highlight=result_backend#std:setting-CELERY_RESULT_BACKEND>`_
+configured.
+If you are using celery 3, use ``health_check_celery3`` instead of ``health_check_celery``.
+
 
 Set up monitoring
 =================

health_check_celery3/plugin_health_check.py

@@ -0,0 +1,23 @@
+from health_check.plugins import plugin_dir
+from health_check.backends.base import BaseHealthCheckBackend, ServiceUnavailable
+from health_check_celery3.tasks import add
+from datetime import datetime, timedelta
+from time import sleep
+
+
+class CeleryHealthCheck(BaseHealthCheckBackend):
+
+    def check_status(self):
+        try:
+            result = add.apply_async(args=[4, 4], expires=datetime.now() + timedelta(seconds=3), connect_timeout=3)
+            now = datetime.now()
+            while (now + timedelta(seconds=3)) > datetime.now():
+                print "            checking...."
+                if result.result == 8:
+                    return True
+                sleep(0.5)
+        except IOError:
+            pass
+        raise ServiceUnavailable("Unknown error")
+
+plugin_dir.register(CeleryHealthCheck)

health_check_celery3/tasks.py

@@ -0,0 +1,7 @@
+from __future__ import absolute_import
+from celery import shared_task
+
+
+@shared_task
+def add(x, y):
+    return x + y