Description

Reactive Programming is a new programming paradigm that’s well suited for applications that are required to perform better under heavy load.

Reactive Programming is built on the foundation of reactive streams specification. Project Reactor is an implementation of Reactive Streams Specification.

Code that’s written using Reactive programming has these qualities:

   Fundamentally Asynchronous
   Non Blocking
   Functional Programming Style of code
   Backpressure support

This course is designed to provide both theoretical and practical knowledge about reactive programming using Project Reactor. This is a pure hands-on oriented course and all the concepts are explained by writing code.

Course Curriculum:

Section 1: Getting Started With the Course

   This section covers the course objectives and the prerequisites that are needed to make the most out of this course.

Section 2: Introduction to Reactive Programming

   In this section, I will introduce you to reactive programming and its related concepts. The following topics are covered in this section
       Why Reactive Programming?
       What is Reactive Programming?
       Introduction to Reactive Streams

Section 3: Getting Started with Project Reactor

   In this section, I will introduce you to the reactive library project reactor, and the reactive types Flux and Mono that forms the foundation for Project Reactor
       Introduction to Project Reactor
       Reactor Reactive Types – Flux and Mono

Section 4: Setting up the Project for this course

   In this section, I will set up the base project that will be used for the rest of this course.

Section 5: Functional Programming in Modern Java

   In this section, I will explain Functional Programming and the benefits that are tied with this programming style
       Imperative Style vs Functional Style

Section 6: Let’s create our very first Flux and Mono

   In this section, I will code and explain the reactor types Flux and Mono using simple examples
   The following topics are covered as part of this lecture:
       Let’s write our very first Flux
       Let’s write our very first Mono
       Reactive Stream Events
       Testing Flux using JUnit5

Section 7: Transforming Flux and Mono

   In this section, I will code and explain different operators that can be used to transform data from one form to another using project reactor
   The following topics are covered as part of this section:
       Transforming Data Using Operators in Project Reactor
       Transform using map() Operator
       Reactive Streams are Immutable
       Filter using filter() Operator
       Advanced transform using the flatMap() Operator
       Asynchronous Operations using flatMap() Operator
       Advanced transform using the concatMap() Operator
       flatMap( ) operator in Mono
       flatMapMany( ) operator in Mono
       Transform using the transform() Operator
       Handling empty data using defaultIfEmpty and switchIfEmpty() Operators

Section 8: Combining Flux and Mono

   In this section, I will code and explain different operators that can be used to combine the reactive streams using project reactor
   The following topics are covered as part of this section:
       Introduction to Combining Reactive Streams
       Combining Reactive Streams using merge() and mergeWith() Operators
       Combining Reactive Streams using mergeSequential() Operators
       Combining Reactive Streams using zip and zipWith() Operators

Section 9: Build Movie ReactiveService using Project Reactor

   In this section, we will build the Reactive MovieService using all the skills that we have acquired so far
   Overview of this MovieService
   Retrieve all of the MovieInfo
   Retrieve MovieInfo by movieId

Section 10: doOn* CallBacks – Peeking into a Sequence

   In this section, I will code and explain the techniques to peek into the individual events that’s emitted by the publisher

Section 11: Exception/Error Handling in Flux and Mono

   In this section, I will cover the different exception handling strategies that are part of the Project reactor
   The following topics are covered as part of this section:
       Exceptions in Reactive Streams
       Introduction to Exception Handling Operators
       onErrorReturn() : Exception Handling Operator
       onErrorResume() : Exception Handling Operator
       onErrorContinue() : Exception Handling Operator
       onErrorMap() : Exception Handling Operator
       doOnError() : Catching Exceptions and Throw the error
       Error Handling Operators in Mono

Section 12: Implement Exception Handling in Movies Reactive Service

   In this section, I will implement the exception handling in the MoviesReactiveService.
       Exception Handling in MoviesReactiveService using onErrorMap
       Test Exception in MoviesReactiveService using Mockito

Section 13 : Retry, Repeat using retry(), retryWhen(), repeat()

   In this section, I will code and implement different techniques to retry the exceptions in the Reactive Streams using Project Reactor
   The following topics are covered as part of this section:
       Retry Exceptions using retry() and retry(n)
       Retry Specific Exceptions using retryWhen()
       Repeat a Sequence using repeat() and repeat(n)
       Repeat a Sequence repeatWhen()

Section 14: Reactors Execution Model – Schedulers, Threads, and Threadpool

   In this section, I will explain the threads and the execution model behind the project reactor
   The following topics are covered as part of this section:
       Reactor Execution Model
       Switching Threads using publishOn()
       Switching Threads using subscribeOn()

Section 15: Making Blocking Calls in MovieReactiveService

   In this section, we will add an enhancement to the MoviesReactive Service by adding a blocking call in to the pipeline.
       Making Blocking calls in MovieReactiveService
           In this lecture, we will code and learn about how to make blocking calls using project reactor

Section 16: BackPressure

   In this section, I will explain the concept of backpressure in reactive programming
   The following topics are covered as part of this section:
       Introduction to BackPressure
       Let’s implement BackPressure
       Write a JUnit test for BackPressure
       Handling Backpressure using onBackpressureDrop()
       Handling Backpressure using onBackpressureBuffer()
       Handling Backpressure using onBackpressureError()

Section 17: Explore Data Parallelism in Project Reactor

   In this section, I will explain about introducing parallelism into the reactive pipeline
   The following topics are covered as part of this section:
       Parallelism using parallel() and runOn() operators
       Parallelism using flatmap() operator
       Parallelism using flatMapSequential() operator

Section 18: Cold & Hot Streams

   In this section, I will explain about cold and hot streams in Reactive Programming
   The following topics are covered as part of this section:
       Cold & Hot Streams
       Cold Streams
       Hot Streams – ConnectableFlux and different options

Section 19: JUnit Testing using VirtualTimeScheduler

   In this section, I will explain the use of VirtualTimer to decrease the execution time of test cases.
       StepVerifier using VirtualTimeScheduler

Section 20: Build NonBlocking RestClient using WebClient

   In this section, we will write a nonblocking rest client using Spring WebClient
   The following topics are covered as part of this section:
       Overview of the Reactive Movie API
       Build the non-blocking MovieInfoService RestClient
       Build the non-blocking Review RestClient
       Build getAllMovies non-blocking MovieReactiveService Client
       Build getMovieById non-blocking MovieReactiveService Client
       Integrate WireMock for Integration Tests

Section 21: Programmatically Creating a Flux

   In this section, I will code and explain the techniques that are available to create a flux programmatically.
   The following topics are covered as part of this section:
       Create a Flux using create()
       Create a Flux using push()

Section 22: Debugging in Project Reactor

   In this section, I will demonstrate different approaches that are available when it comes to debugging reactor error messages.
   The following topics are covered as part of this section:
       Debug Exceptions using “checkpoint” operators
       Debug Exceptions using Hooks.onOperatorDebug()
       Production-ready Global Debugging using “ReactorDebugAgent”

By the end of this course, you will have a complete understanding of Reactive Programming, write code using the Reactive Programming Principles, and when to use them in your project.
Who this course is for:

   Any Java Developer who is interested in exploring Reactive Programming
   Any Java Developer who has the need to write fast performing code under heavy load
   Any Java Developer who is interested in learning all the features of the “Reactor” Reactive Programming Library

Requirements

   Prior Java Experience is mandatory
   Experience writing test cases using JUnit
   Experience working with Intellij or any other IDE

Last Updated 5/2021