# Fedora Messaging Task

1. Install fedora messaging using pip. Inside virtual environment.
> pip install fedora-messaging
2. Install and run rabbitmq.
> sudo apt-get install rabbitmq-server
> sudo service rabbitmq-server start
3. Enable web interface
> sudo rabbitmq-plugins enable rabbitmq_management
4. Login with the credentials
5. Create fedora.toml file with the following sample configration.

# A basic configuration for Fedora's message broker, using the example callback
# which simply prints messages to standard output.
#
# This file is in the TOML format.
amqp_url = "amqps://fedora:@rabbitmq.fedoraproject.org/%2Fpublic_pubsub"
# callback = "fedora_messaging.example:printer"

[tls]
ca_cert = "cacert.pem"
keyfile = "fedora-key.pem"
certfile = "fedora-cert.pem"

[client_properties]
app = "Fedora Messaging Application"
# Some suggested extra fields:
# URL of the project that provides this consumer
app_url = "https://github.com/fedora-infra/fedora-messaging"
# Contact emails for the maintainer(s) of the consumer - in case the
# broker admin needs to contact them, for e.g.
app_contacts_email = ["[e-mail]"]

# [exchanges."amq.topic"]
# type = "topic"
# durable = true
# auto_delete = false
# arguments = {}

# Queue names *must* be in the normal UUID format: run "uuidgen" and use the
# output as your queue name. If your queue is not exclusive, anyone can connect
# and consume from it, causing you to miss messages, so do not share your queue
# name. Any queues that are not auto-deleted on disconnect are garbage-collected
# after approximately one hour.
#
# If you require a stronger guarantee about delivery, please talk to Fedora's
# Infrastructure team.
[queues.00000000-0000-0000-0000-000000000000]
durable = false
auto_delete = true
exclusive = true
arguments = {}

# [[bindings]]
# queue = "00000000-0000-0000-0000-000000000000"
# exchange = "amq.topic"
# routing_keys = ["#"]  # Set this to the specific topics you are interested in.

[consumer_config]
example_key = "for my consumer"

[qos]
prefetch_size = 0
prefetch_count = 25

[log_config]
version = 1
disable_existing_loggers = true

[log_config.formatters.simple]
format = "[%(levelname)s %(name)s] %(message)s"

[log_config.handlers.console]
class = "logging.StreamHandler"
formatter = "simple"
stream = "ext://sys.stdout"

[log_config.loggers.fedora_messaging]
level = "INFO"
propagate = false
handlers = ["console"]

[log_config.loggers.twisted]
level = "INFO"
propagate = false
handlers = ["console"]

[log_config.loggers.pika]
level = "WARNING"
propagate = false
handlers = ["console"]

# If your consumer sets up a logger, you must add a configuration for it
# here in order for the messages to show up. e.g. if it set up a logger
# called 'example_printer', you could do:
#[log_config.loggers.example_printer]
#level = "INFO"
#propagate = false
#handlers = ["console"]

[log_config.root]
level = "ERROR"
handlers = ["console"]

NOTE - Change the path of ca_cert, keyfile, certfile based on filepath in your system.

5. Create a file publish.py to publish the message. Save the file and give the needed file permissions.
> chmod +x publish.py

from fedora_messaging.api import publish, Message
from fedora_messaging.config import conf
conf.setup_logging()
message = Message(
topic="tutorial.topic",
body={"Hello": "World"}
)
publish(message)

6. Likewise create another file consume.py with the below mentioned code snippet. Give the file permissions.
> chmod +x consume.py

from fedora_messaging.api import consume
from fedora_messaging.config import conf

def print_message(message):
	print(message)

if __name__ == "__main__":
    conf.setup_logging()
    consume(print_message)

7. Open two terminals. Run the consume.py file first using ./consume.py on one, so that it keeps listening.
8. On another terminal, run command ./publish.py.
9. Output - Now, you'll see the topic, header, message that was being published appear on the terminal where consume.py is listening.

Shows the output of ./consume.py terminal.

Things to take care of

1. All the needed certification files can be taken from the projects [github repo](https://github.com/fedora-infra/fedora-messaging/tree/master/configs).
2. Before publishing the message make sure that consume.py is already running(listening). Only then you'll be able to see the published messages.

Resources
1. Documentation Fedora messaging - https://fedora-messaging.readthedocs.io/en/stable/tutorial/installation.html