Reactive programming is a modern programming concept. Asynchronous and non-blocking time dependent Data stream based are some of the characteristics of Reactive Programming(RP). Continuous stream of Data which originates from any source is called a Data stream. Some examples of Data streams are mouse click events, IoT sensor data. Loosely such a Data stream can be thought of as an Observable. In real life, the status of a parcel sent through BlueDart or FedEx can be thought of as a good example of an observable.
Only when an observer connects with such Data stream, it can be defined as an Observable. For Observable to come to life, there has to be an observer. In the world of Reactive programming Observable is the core data type. The other Data types such as observer, subscriber, filter, scheduler are sattelite data types
Reactive Extensions to Java script(RxJS) is a library which can be used with JS to build a Reactive program. Prior to this RP developemt, with JS, AJAX and with the use of promises and callbacks, programmers were indeed developing Asynchronous programs. But with RxJS, it is just few lines of code. Also promises can't be closed but observables can be closed and exited.
NodeJS, NPM, RxJS, webpack, babble are few more software tools which help in building Reactive programs.
Demonstartion
Login to sambath@dhruv and go to UNIV-CS-CLOUD/Reactive-Computing-with-RxJS/REACTIVE-PROGRAMMING/rxjsproj
You can see relevant files/folders such as webpack.config.js, package.json, public/index.html and dist/main.js, node_modules
Laumch the program as follows
npm run publish
while it is running, open a browser and go to http://localhost:8080/
In the browser console you can observe the observables .
Code, presentation can be downloaded from