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Publish/Subscribe pattern
Introduce the Publish/Subscribe pattern to provide a flexible event-handling system.
The Publish/Subscribe pattern is a messaging paradigm used in software architecture with several key points:
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Decoupling of publishers and subscribers: Publishers and subscribers operate independently, and there's no direct link between them. This enhances the scalability and modularity of applications.
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Event-driven communication: The pattern facilitates event-driven architectures by allowing publishers to broadcast events without concerning themselves with who receives the events.
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Dynamic subscription: Subscribers can dynamically choose to listen for specific events or messages they are interested in, often by subscribing to a particular topic or channel.
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Asynchronous processing: The pattern inherently supports asynchronous message processing, enabling efficient handling of events and improving application responsiveness.
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Scalability: By decoupling senders and receivers, the pattern can support a large number of publishers and subscribers, making it suitable for scalable systems.
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Flexibility and adaptability: New subscribers or publishers can be added to the system without significant changes to the existing components, making the system highly adaptable to evolving requirements.
Acceptance Criteria:
- The implementation must follow the project's coding standards and directory structure as outlined in the contribution guidelines.
- Comprehensive unit tests must cover the new pattern implementation, ensuring all major use cases are accounted for.
- Documentation must be provided, explaining the pattern, its use cases, and how the implementation solves a particular problem, including UML diagrams where applicable.
I have an implementation of the pattern. However I am finding it difficult to test since the implementation is quite basic given the asynchronous/threading code is handled by JMS which shouldn't be tested since its a third party software. I can create a pull request and the current tests can be viewed, perhaps you'll find it satisfactory. If not, I am happy to receive criticism to improve my testing, it can improve my knowledge.