https://github.com/lbwa/observer-vs-pub-sub

differences between observer pattern and publish-subscribe pattern
https://github.com/lbwa/observer-vs-pub-sub

design-patterns observer publish-subscribe

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differences between observer pattern and publish-subscribe pattern

• Host: GitHub
• URL: https://github.com/lbwa/observer-vs-pub-sub
• Owner: lbwa
• Created: 2020-02-05T15:15:57.000Z (almost 5 years ago)
• Default Branch: master
• Last Pushed: 2020-02-06T05:53:55.000Z (almost 5 years ago)
• Last Synced: 2024-11-05T22:11:58.520Z (2 months ago)
• Topics: design-patterns, observer, publish-subscribe
• Language: TypeScript
• Size: 16.6 KB
• Stars: 0
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

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README

        
Observer vs Pub-Sub pattern




  

    

  



> Differences between [observer pattern][wiki-observer-pattern] and [publish-subscribe pattern][wiki-publish-subscribe-pattern].

[wiki-observer-pattern]: https://en.wikipedia.org/wiki/Observer_pattern

[wiki-publish-subscribe-pattern]: https://en.wikipedia.org/wiki/Publish%E2%80%93subscribe_pattern

## Includes

This repository has included 2 kinds of design patterns in the `/packages` directory.

1. [Observer pattern](./packages/observer)

1. [Publish-Subscribe pattern](./packages/pub-sub)

### Differences

1. In the Observer pattern, the Observers are aware of the Subject, also the Subject maintains a record of the Observers. Whereas, in Publisher/Subscriber, publishers and subscribers don’t need to know each other. They simply communicate with the help of message queues or broker.

2. In Publisher/Subscriber pattern, components are loosely coupled as opposed to Observer pattern.

   Observer pattern is mostly implemented in a synchronous way, i.e. the Subject calls the appropriate method of all its observers when some event occurs. The Publisher/Subscriber pattern is mostly implemented in an asynchronous way (using message queue).

3. Observer pattern needs to be implemented in a single application address space. On the other hand, the Publisher/Subscriber pattern is more of a cross-application pattern.

## Test

- Run all tests

  ```bash

  yarn test

  ```

- Observer pattern

  ```bash

  yarn test:observer

  ```

- Publish-subscribe pattern

  ```bash

  yarn test:pub-sub

  ```

## Acknowledgement

1. [hackernoon - observer vs pub-sub](https://hackernoon.com/observer-vs-pub-sub-pattern-50d3b27f838c)

1. [stackoverflow - Difference between Observer, Pub/Sub, and Data Binding](https://stackoverflow.com/questions/15594905/difference-between-observer-pub-sub-and-data-binding)

1. [Addy Osmani - Learning JavaScript Design Patterns](https://addyosmani.com/resources/essentialjsdesignpatterns/book/#observerpatternjavascript)

## License

MIT © [Bowen](https://set.sh)