Requirements

Content Table

• Functional Requirements
  • Create Queues or Topics (Admin)
  • User Authentication
  • User Subscription Queue/Topic
  • User Unsubscription Queue/Topic
  • User Publish Message Queue/Topic
  • User Consume Message Queue/Topic
• Non-Functional Requirements
  • Availability
  • Replication
  • Partitioning
  • Security (Authentication)
  • Error Handling (Failover and Failback)

Functional Requirements

The following functional requirements define the core capabilities of the MOM Server, a distributed messaging system built with FastAPI, Redis, gRPC, ZooKeeper, and NGINX, designed to manage queues and topics with administrative and user interactions.

FR01 - Create Queues or Topics (Admin)

Field	Value
ID	FR01
Name	Create Queues or Topics
Actor	Administrator
Version	1.0
Epic	Message Handling
Priority	High

• Description: As an Administrator, I must be able to create message queues or topics to facilitate asynchronous communication within the system.

FR02 - User Authentication

Field	Value
ID	FR02
Name	User Authentication
Actor	Administrator, User
Version	1.0
Epic	Security
Priority	High

• Description: As an Administrator or User, I must be able to authenticate with the system to securely access its features.

FR03 - User Subscription Queue/Topic

Field	Value
ID	FR03
Name	User Subscription Queue/Topic
Actor	User
Version	1.0
Epic	Message Handling
Priority	Medium

• Description: As a User, I must be able to subscribe to queues or topics to receive messages published to them.

FR04 - User Unsubscription Queue/Topic

Field	Value
ID	FR04
Name	User Unsubscription Queue/Topic
Actor	User
Version	1.0
Epic	Message Handling
Priority	Medium

• Description: As a User, I must be able to unsubscribe from queues or topics to stop receiving messages from them.

FR05 - User Publish Message Queue/Topic

Field	Value
ID	FR05
Name	User Publish Message Queue/Topic
Actor	User
Version	1.0
Epic	Message Handling
Priority	High

• Description: As a User, I must be able to publish messages to queues or topics for distribution to subscribers or consumers.

FR06 - User Consume Message Queue/Topic

Field	Value
ID	FR06
Name	User Consume Message Queue/Topic
Actor	User
Version	1.0
Epic	Message Handling
Priority	High

• Description: As a User, I must be able to consume messages from queues or topics to process or retrieve them.

Non-Functional Requirements

The following non-functional requirements ensure the MOM Server meets quality standards, reflecting its distributed architecture with FastAPI, Redis, gRPC replication, ZooKeeper coordination, and NGINX load balancing across three AWS EC2 instances.

NFR01 - Availability

Field	Value
ID	NFR01
Name	Availability
Category	Reliability
Priority	High

• Description: The system must maintain high availability through replication and failover mechanisms to ensure continuous operation across three instances, minimizing downtime.

NFR02 - Replication

Field	Value
ID	NFR02
Name	Replication
Category	Reliability
Priority	High

• Description: The system must replicate queue and topic data across all instances using gRPC to ensure data consistency and support availability.

NFR03 - Partitioning

Field	Value
ID	NFR03
Name	Partitioning
Category	Scalability
Priority	Medium

• Description: The system must support partitioning of queues and topics across instances, managed by ZooKeeper, to distribute load and enable scalability.

NFR04 - Security (Authentication)

Field	Value
ID	NFR04
Name	Security (Authentication)
Category	Protection
Priority	High

• Description: The system must enforce secure authentication for all users and administrators, protecting access to queues, topics, and administrative functions.

NFR05 - Error Handling (Failover and Failback)

Field	Value
ID	NFR05
Name	Error Handling (Failover and Failback)
Category	Reliability
Priority	High

• Description: The system must handle errors through failover (reassigning queues/topics to other instances via ZooKeeper) and failback (restoring data from centralized backup Redis) to ensure resilience.