From 24ac5b33f8290c69fc28744c1e105697215ca726 Mon Sep 17 00:00:00 2001
From: Sean Fairbanks <64443628+pysean3@users.noreply.github.com>
Date: Tue, 9 Feb 2021 22:22:46 -0800
Subject: [PATCH] Add example of health check url
An example of a local python http server which returns a 200 or 500 response depending on cluster health.
---
docs/examples.rst | 80 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 80 insertions(+)
diff --git a/docs/examples.rst b/docs/examples.rst
index 62b0811b..a49de4f9 100644
--- a/docs/examples.rst
+++ b/docs/examples.rst
@@ -307,6 +307,86 @@ Alternatively the ``parzen_async()`` function can also be written with :func:`as
return result(result_id, wait=10000, cached=True)
+
+Http Health Check
+============
+An example of a python http server you can use (localhost:8080) to validate the health status of all the clusters in your environment. Example is http only.
+
+Requires cache to be enabled. Save file in your Django project's root directory and run with command: ``python worker_hc.py`` in your container or other environment. Can be customized to show whatever you'd like from the Stat class or modified as needed.
+
+.. code-block:: python
+
+ from http.server import BaseHTTPRequestHandler, HTTPServer
+ from mtt_app.settings.base import EMAIL_USE_TLS
+
+ import os
+ import django
+
+ # Set the correct path to you settings module
+ os.environ.setdefault("DJANGO_SETTINGS_MODULE", "my.settings.path")
+
+ # All django stuff has to come after the setup:
+ django.setup()
+
+ from django_q.monitor import Stat
+ from django_q.conf import Conf
+
+ # Set host and port settings
+ hostName = "localhost"
+ serverPort = 8080
+
+
+ class HealthCheckServer(BaseHTTPRequestHandler):
+ def do_GET(self):
+
+ # Count the clusters and their status
+ happy_clusters = 0
+ total_clusters = 0
+
+ for stat in Stat.get_all():
+ total_clusters += 1
+ if stat.status in [Conf.IDLE, Conf.WORKING]:
+ happy_clusters += 1
+
+ # Return 200 response if there is at least 1 cluster running,
+ # and make sure all running clusters are happy
+ if total_clusters and happy_clusters == total_clusters:
+ response_code = 200
+ else:
+ response_code = 500
+
+ self.send_response(response_code)
+ self.send_header("Content-type", "text/html")
+ self.end_headers()
+
+ self.wfile.write(
+ bytes("Django-Q Heath Check", "utf-8")
+ )
+ self.wfile.write(
+ bytes(f"Health check returned {response_code} response
", "utf-8")
+ )
+ self.wfile.write(
+ bytes(
+ f"{happy_clusters} of {total_clusters} cluster(s) are happy
",
+ "utf-8",
+ )
+ )
+
+
+ if __name__ == "__main__":
+ webServer = HTTPServer((hostName, serverPort), HealthCheckServer)
+ print("Server started at http://%s:%s" % (hostName, serverPort))
+
+ try:
+ webServer.serve_forever()
+ except KeyboardInterrupt:
+ pass
+
+ webServer.server_close()
+ print("Server stopped.")
+
+
+
.. note::
If you have an example you want to share, please submit a pull request on `github `__.