Introduction to Reactive Spring (TT3355) (AA-TT3355)

Spring Data reactive allow us to implement database operations relying on Reative Programming APIs. While the Spring R2DBC initiative aims to bring reactive programming to relational databaes, several NoSQL databases already provide this possibility. After an introduction to NoSQL and the MongoDB, this courses covers the APIs available to communicate with this NoSQL database using both blocking and reactive APIs.

Introdcution to Reactive Spring is a comprehensive Java training workshop geared for experienced developers who wish to explore concurrent, asynchronous and reactive programming APIs and techniques using Spring. After an introduction to reactive programming, Reactive Streams and the Project Reactor APIs, this course will show how this APIs are integrated into Spring. Spring 5 includes Spring WebFlux, providing a reactive programming model for web applications, including support for Reactive REST APIs. Spring WebSocket assists in the creation of web applications which provide a full-duplex, two-way communication between client and server.

Session: Introduction to Reactive Programming

Lesson: Introduction to Reactive Programming

• Reactive Manifesto
• Introduce ReactiveX
• ReactiveX implementations
• The Observer, Iterator pattern and functional programming
• Discuss hot and cold publishers

Lesson: Reactive Streams API

• Introduce the Reactive Streams specification
• Publisher and Subscribers
• util.concurrent.Flow
• Transformation of Messages (Processor)
• Controlling messages

Session: Project Reactor

Lesson: Introduction

• Introduce the Reactor Building blocks
• Flux and Mono
• Creating observables
• Subscribing to a stream

Lesson: Testing Event Sources (introduction)

• Testing reactive implementations
• StepVerifier : test sequence of emitted items
• Defining expectations
• TestPublisher: produce test data to test downstream operators

Lesson: Reactive Operators

• Introduce Operators
• Show the use of marble diagrams
• Explain some commonly used operators
• Callback operators

Lesson: Schedulers (Multithreading)

• Thread usage of subscriber and consumer
• Using the subscribeOn method
• Introduce the Scheduler interface
• Using the observeOn method

Lesson: Backpressure

• Strategies for dealing with Backpressure
• "reactive pull" backpressure

Lesson: Exception Handling

• Handling errors in onError
• Exception handling strategies
• Using onErrorReturn or onErrorNext operators
• Using the retry operators
• The Global Error Handler

Session: Spring Data R2DBC

Lesson: Spring Data Review

• Quick review of Spring Data repositories
• Query return types
• Defining Query methods
• Pagination and sorting

Lesson: R2DBC

• Reactive Relational Database Connectivity
• DatabaseClient
• Performing CRUD operations
• Reactive Query annotated methods

Session: Spring WebFlux

Lesson: Introduction

• Annotated Controllers
• Functional Endpoints
• WebFlux configuration
• Creating a reactive REST endpoint

Lesson: Defining flows

• Defining the application flow
• Actions
• Defining decision
• Navigating flows
• RouterFunction

Lesson: View Technologies

• View technologies
• Using Thymeleaf to create the view
• View Configuration

Session: Spring WebClient

Lesson: Introduction to WebClient

• Working with asynchronous and streaming APIs
• Making requests
• Handling the response

Lesson: WebTestClient

• Testing WebFlux server endpoints
• Testing controllers or functions
• Define integration tests

Session: Spring Reactive WebSockets

Lesson: Introduction to WebSockets

• Be familiar with the basics of WebSockets
• Understand the HTTP handshake and upgrade
• Name some of the advantages of WebSockets

Lesson: Defining the WebSocket

• WebSocket Message Handling
• WebSocketSession
• Implementing the WebSockethandler
• Creating a Browser WebSocket Client

Lesson: WebSocket STOMP

• Streaming (or Simple) text-orientated messaging protocol
• Introduce SockJS
• Connecting to the STOMP endpoint
• Configuring the message broker
• STOMP destinations

Lesson: Reactive WebSocket

• Reactive WebSocket support
• Implement the reactive WebSocketHandler

Session: NOSQL and MongoDB

Lesson: BigData

• Introduce Big Data
• Explain the need for enhanced data storage

Lesson: Introduction to MongoDB

• JavaScript Object Notation Overview
• Introduce Binary JSON (BSON)
• Starting the database
• Creating Collections and Documents
• Executing ësimpleí database commands
• Introduce the ObjectID
• Searching for documents using query operators
• Updating and deleting documents
• MongoDB Compass

Session: Spring and MongoDB

Lesson: Spring and MongoDB

• MongoDB Support in Spring Data
• MongoClient and MongoTemplate
• Spring Data MongoDB configuration
• @EnableMongoRepositories
• Adding documents to the database
• The @Document and @Field annotations
• Polymorphism and the _class property
• The Criteria object

Lesson: Spring Data MongoDB

• MongoRepository
• Field naming strategy
• Using JSON queries to find documents
• The @PersistenceConstructor annotation

Lesson: Reactive Repositories with MongoDB

• Using reactive repositories
• ReactiveMongoTemplate
• RxJava or Reactor

Reactive Spring focuses on providing an understanding of the fundamental principles and technologies that are used in reactive programming. This understanding is critical to being able to diagnose, troubleshoot, tune, and perform other lifecycle activities.

Working within in an engaging, hands-on learning environment, guided by our expert team, attendees will:

• Understand the ReactiveX specification
• Understand the basics of Reactive Programming
• Discuss the advantages and limitations of Observables
• Write a client application capable of handling Reactive events
• Apply operators to event streams to filter, modify and combine the objects emitted by event publishers
• Select the appropriate type of Event Source
• Use both Cold and Hot Observables
• Deal with backpressure problems in reactive programming
• Develop a reactive web application using Spring WebFlux
• Define application flows of a WebFlux application
• Use the WebClient API to work with both synchronous and streaming APIs
• Develop Unit and Integration tests to test WebFlux endpoints
• Creating a reactive REST endpoint
• Become familiar with the basics of WebSockets
• Create a WebSocket endpoint using Spring
• Create a WebSocket client
• Understand the basics of NoSQL
• Become familiar with the basics of MongoDB
• Understand how the data in MongoDB can be retrieved using a Reactive API
• Define Spring Data MongoDB repositories
• Query the MongoDB using Spring Data
• Define a reactive repository using MongoDB
• Explore the Spring Data R2DBC API to perform reactive CRUD operations against a relational database

This in an intermediate-level development course geared for students experienced with Java and Spring programming essentials.

In order to be successful in the hands-on portion of the training, you should have incoming practical, hands-on prior experience working with basic Spring concepts and development skills (or attended the suggested pre-requisite courses listed below). This course does not cover Java or Spring development basics.

Do you have more questions? We're delighted to assist you!

• This hands-on course focuses on "learning by doing", combining expert lecture, practical demonstrations and group discussions with plenty of machine-based real-world programming labs and exercises. Student machines are required.

Java Developers, Application Developers, Full Stack Developers, Technical Managers, Architects.