added rabbitmq helpers and setup command

rmq_helper/exchanges.py

@@ -0,0 +1,31 @@
+import json
+
+from pika.adapters.blocking_connection import BlockingChannel
+
+from .extension import with_pika_channel
+
+
+@with_pika_channel
+def ensure_exchange_exists(name: str, channel: BlockingChannel = None) -> None:
+    """Ensures exchange exists
+
+    :param name: the name of the exchange
+    :param channel: a pika channel, if none specified a new one will be created
+    """
+    channel.exchange_declare(exchange=name, exchange_type='topic')
+
+
+@with_pika_channel
+def exchange_publish(exchange_name: str, topic: str, message, channel: BlockingChannel = None):
+    """Publishes a message to a
+
+    :param exchange_name: the name of the exchange
+    :param topic: the topic to publish to
+    :param message: the message to publish (will be turned into a json)
+    :param channel: a pika channel, if none specified a new one will be created
+    """
+    ensure_exchange_exists(exchange_name, channel=channel)
+
+    body = json.dumps(message)
+    body_bytes = body.encode('utf-8')
+    channel.basic_publish(exchange=exchange_name, routing_key=topic, body=body_bytes)