eyjan-huang / pub-sub-system

This is the project to build a publisher-subscriber system using Go

Table of Contents

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• Table of Contents
• Background
• Install
• Architecture
• Usage
• Maintainers
• Acknowledgment
• Reference

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Background

This project builds a simple prototype of publish-subscribe system using Go.

• Server: mainly implemented with Bully Algorithm for leader election.
• Client: mainly works in subscribe/publish/unsubscribe from the server.

The servers are able to communicate with each other, and the clients as well. Server may store the topic and any relevant content of the topic. Clients is able to subscribe or unsubsribe the topic. If a client is the follower of a specific topic. Then he/she is able to publish the content. Once the content is updated, the rest of all the client who subsribes this topic, will be informed as well.

From the server side, if the topic is being updated, the leader should broadcast this update to all the follower. If it is the follower who got this message, it will firstly report this update to the leader, then the leader will repeat the broadcast process.

Install

Before you clone or download the project via git or other methods manually. Make sure the version of Go in your local machine is consistent with Go.mod

Architecture

- pub-sub
    - client
        - index.go
    - server
        - index.go
        - peer-conn.go
        - peer-mgr.go
        - server.go
        - subscription-mgr.go
    - domain
        - message.go
    - go.mod
    - main.go
    - README.md

1. client only works in pub/sub process。
2. server defines how the server should work. Their communication between the servers will be manged by peer-mgr and peer-conn.
3. domain defines how the meesage format should be like. It is similar to a self-defined protocol
4. go.mod defines the version of Go.
5. main.go, the entrance of the whole program.

Usage

Once you have make it available on your local machine. It is the time to make it run and play with it. The commands are slightly different for server and client, let's read it one by one:

• Server:go run main.go [-server-addr ip:port_number]

The server-addr is not required. If you do not specify the ip address with port number, it uses the default one (127.0.0.1:8000)

To initialize multiple server, you MUST given different port number or OS would not allow it.

We recommend you use the local host as the IP address 127.0.0.1 for local testing

• Client: go run main.go -mode client

To run a client, you must specify the -mode as client or it runs in server mode by default

The server address and port number are not required. It uses local host as IP address and port number are randomly assigned.

After you run the command successfully in the terminal. You may see the following interface:

Supported Commands:
-> Subsribe: s <topic>
-> Publish: p <topic> <content>
-> Unsubscribe: u <topic>

Based on the hint previously, we do a sample for demonstrate:

• Subscribe a topic named Music s Music
• Publish a content Love Story under topic Music p Music Love Story
• Unsubsribe from Music u Music

Maintainers

• @Eyjan-Huang
• @Jingyi96
• @Jenny

Acknowledgment

We all sincerely appreciate the academic materials provided by Prof. Moazzeni. Also we acclaim the help provided by @ninomiyx for providing us a general framework of how pub/sub system work. We honestly acclaim how complicated when implementing such system in programming language.

Reference

1. What is Pub/Sub?
2. Publish-subscribe pattern
3. python-pubsub