This repository is for an api that is receiving three requests: /latest, /post and /status. The /post requests will be going through queue using RabbitMQ system.

* Abstract

RabbitMQ is a message-oriented middleware system with advanced message queuing protocol.

Link to rabbitMQ official

To setup our RabbitMQ queuing protocol, we made an account in CloudAMQP which are managed RabbitMQ servers in the cloud. Messages are published to a queue by a producer (Helge-api/app/producer.py). Consumers (Backend) can then get the messages from the queue when the consumer wants to handle the messages.

Messages can be sent cross languages, platforms and OS, this way of handling messages, decouple your processes and creates a scalable system.

* Usage in this project

For starters, we create a CloudAMQP instance by signing up as a customer. There we assigned HackerNews instance which provided us with a url, that is used in Helge-api/app/producer.py for establishing connection using pika (Pika is a pure-Python implementation of the AMQP protocol).

* Helge-api/app/producer.py:

# Establish a connection with RabbitMQ server.
url = 'amqp://pgkettyz:PIjFclgL5aB8c0ZP4OwWUZZ3DbgKEriY@raven.rmq.cloudamqp.com/pgkettyz'
connection = pika.BlockingConnection(pika.ConnectionParameters(url))
channel = connection.channel()

Afterwards we create a queue 'Helge-api-posts' to which the messages will be delivered.

channel.queue_declare(queue='Helge-api-posts')

Then we created a definition that sends POST to 'Helge-api-posts' queue serialized as a json.dump as we can't send Python types as payload.

def post_to_queue(message):
    channel.basic_publish(exchange='',
                          routing_key='Helge-api-posts',
                          body=json.dumps(message),
                          properties=pika.BasicProperties(
                             delivery_mode=2,  # make message persistent
                          ))