SDLE First Assignment

A Reliable publish-subscribe service that guarantees "exactly-once" delivery of the messages on top of ZeroMQ. Essentially, the system is composed of subscribers and publishers. The publishers can publish a message on a topic and the subscribers of a determined topic receive the messages posted on that topic. Developed in the course of Large Scale Distributed Systems by group T01G14.

Group members:

1. Emanuel Trigo (up201605389@edu.fe.up.pt)
2. Fábio Huang (up201806829@edu.fe.up.pt)
3. Sara Pereira (up202204189@edu.fe.up.pt)
4. Valentina Wu (up201907483@edu.fe.up.pt)

Installation and prerequisite

1. Install Python3, see official website
2. Install ZeroMQ, see official website
3. Clone this repository:

git clone https://git.fe.up.pt/sdle/2022/t1/g14/proj1.git

4. Head inside the this project folder, run the following command to install the necessary libraries:

pip install -r requirements.txt

Usage Guide

For this publish-subscribe service:

• The Clients:

  • Are able to do the following operations:
    • SUB - Subscribes a Topic
    • UNSUB - Unsubscribes a Topic
    • PUT - Publishes a Message on a Topic
    • GET - Retrieves a Message from a Topic
  • Topics are identified by an arbitrary string
  • Topics are created implicitly when a subscriber subscribes to a topic that does not exist yet.
  • All subscriptions are durable, according to the Java Message Service's (Jakarta Messaging) terminology.
  • A topic's subscriber should get all messages put on a topic, as long as it calls GET enough times, until it explicitly unsubscribes the topic

• The Server:

  • Receives the operations mentioned above from the clients and reacts to them accordingly

How to run

Server Side Application

Using the Command Line, for Windows users, inside the /src directory:

python server.py

Using the Command Line, for Linux or MacOS users, inside the /src directory:

python3 server.py

Note: Only one server should be running at a time

Client Side Application

Using the Command Line, for Windows users, inside the /src directory:

python client.py <CLIENT_ID>

Using the Command Line, for Linux or MacOS users, inside the /src directory:

python3 client.py <CLIENT_ID>

Note: More than one client can be initiated, as long as the <CLIENT_ID> are different from each other

While the Client Application is running, the following operation commands can be sent to the server side:

SUB <TOPIC_NAME>

UNSUB <TOPIC_NAME>

GET <TOPIC_NAME>

PUT <TOPIC_NAME> <MESSAGE_CONTENT>

For example, to PUT a message "Porto is very hot today" to the Topic "weather", enter:

PUT weather Porto is very hot today