aboutsummaryrefslogtreecommitdiffstats
path: root/dashboard_notification/notification.py
diff options
context:
space:
mode:
Diffstat (limited to 'dashboard_notification/notification.py')
-rw-r--r--dashboard_notification/notification.py120
1 files changed, 120 insertions, 0 deletions
diff --git a/dashboard_notification/notification.py b/dashboard_notification/notification.py
new file mode 100644
index 0000000..6843c76
--- /dev/null
+++ b/dashboard_notification/notification.py
@@ -0,0 +1,120 @@
+##############################################################################
+# Copyright (c) 2016 Max Breitenfeldt and others.
+#
+# All rights reserved. This program and the accompanying materials
+# are made available under the terms of the Apache License, Version 2.0
+# which accompanies this distribution, and is available at
+# http://www.apache.org/licenses/LICENSE-2.0
+##############################################################################
+
+import jsonpickle
+import pika
+
+
+class Message(object):
+ def __init__(self, type, topic, content):
+ self.type = type
+ self.topic = topic
+ self.content = content
+
+
+class Notification(object):
+ """
+ This class can be used by the dashboard and the labs to exchange notifications about booking
+ events and pod status. It utilizes rabbitmq to communicate.
+
+ Notifications are associated to an event and to a topic.
+ Events are:
+ [ 'booking_start', 'booking_end']
+ The topic is usually a POD name, ie:
+ 'Intel POD 2'
+ """
+
+ def __init__(self, dashboard_url, user=None, password=None, verbose=False):
+ self.rabbitmq_broker = dashboard_url
+ self.verbose = verbose
+ if user is None and password is None:
+ self._connection = pika.BlockingConnection(pika.ConnectionParameters(
+ host=self.rabbitmq_broker))
+ else:
+ self.credentials = pika.PlainCredentials(user, password)
+ self._connection = pika.BlockingConnection(pika.ConnectionParameters(
+ credentials=self.credentials,
+ host=self.rabbitmq_broker))
+ self._registry = {}
+ self._channel = self._connection.channel()
+ self._channel.exchange_declare(exchange='notifications', type='topic')
+ self._result = self._channel.queue_declare(exclusive=True, durable=True)
+ self._queue_name = self._result.method.queue
+
+ def __enter__(self):
+ return self
+
+ def __exit__(self, exc_type, exc_val, exc_tb):
+ self._connection.close()
+
+ def register(self, function, topic, type='all'):
+ """
+ Registers a function to be called for the specified event.
+ :param function: the function to register
+ :param event: the event type
+ :param regex: a regex to specify for wich topics the function will be called. Some
+ possible Expressions can be:
+ 'Intel POD 2' : Intel POD 2
+ """
+
+ if topic not in self._registry:
+ self._registry[topic] = [(function, type)]
+ else:
+ self._registry[topic].append((function, type))
+
+ def receive(self):
+ """
+ Start receiving notifications. This is a blocking operation, if a notification is received,
+ the registered functions will be called.
+ """
+ if self.verbose:
+ print('Start receiving Notifications. Keys: ', self._registry.keys())
+ self._receive_message(self._registry.keys())
+
+ def send(self, message):
+ """
+ Send an event notification.
+ :param event: the event type
+ :param topic: the pod name
+ :param content: a JSON-serializable dictionary
+ """
+ self._send_message(message)
+
+ def _send_message(self, message):
+ routing_key = message.topic
+ message_json = jsonpickle.encode(message)
+ self._channel.basic_publish(exchange='notifications',
+ routing_key=routing_key,
+ body=message_json,
+ properties=pika.BasicProperties(
+ content_type='application/json',
+ delivery_mode=2, # make message persistent
+ ))
+ if self.verbose:
+ print(" [x] Sent %r:%r" % (routing_key, message_json))
+
+ def _receive_message(self, binding_keys):
+ for key in binding_keys:
+ self._channel.queue_bind(exchange='notifications',
+ queue=self._queue_name,
+ routing_key=key)
+ self._channel.basic_consume(self._message_callback,
+ queue=self._queue_name)
+ self._channel.start_consuming()
+
+ def _message_callback(self, ch, method, properties, body):
+ if self.verbose:
+ print(" [x] Got %r:%r" % (method.routing_key, body))
+ if method.routing_key not in self._registry:
+ return
+ for func, type in self._registry[method.routing_key]:
+ message = jsonpickle.decode(body.decode())
+ if message.type == type:
+ func(message)
+ ch.basic_ack(delivery_tag=method.delivery_tag)