The document discusses building microservices using Vert.x 3.0, highlighting the advantages of a microservices architecture over monolithic systems, such as modularity, independent development, and easy scalability. It covers key Vert.x concepts, including event loops, verticles, and event buses, alongside various modules for web development, data access, and authentication. Additionally, the document outlines practical implementations and comparisons with other frameworks like Node.js and Netty.

1. BUILDING MICROSERVICES
WITH VERT.X 3.0
AGRAJ MANGAL

2. AGENDA
• Microservices
• Why, why not ?
• Comparison with Monolithic Architecture
• Vert.x
• Concepts: Event Loop, Verticles, Event Bus
• Modules: core, web
• Comparisons
• Real-life Example - Pulse

3. MONOLITHIC ARCHITECTURE
• Logically Different Modules
• But Packaged & deployed as a Single Unit
• Initial Phases of Project
• Simple to Deploy
• Vertical Scaling
• Later on
• Difficult to Manage & Scale
• Longer Startup Times
• Slow down Development
• CI becomes challenging

5. MICROSERVICES PATTERN
• Split into Smaller, Interconnected Services
• Loose Coupling
• Service == Functional Area
• Service exposes APIs – consumed by other services & clients

7. FINE GRAINED VIEW

8. BENEFITS
• Enforces Modularity
• Decomposing complexity
• Manageable chunks
• Each service – well defined boundary
• Independent Development
• Different Teams
• Different Technologies
• Easy to test
• Scaling is Easy
• Each service can be scaled independently
• Different Service might have different requirements ( CPU, Memory )

9. SCALING
MICROSERVICES

10. SERVICES
COMMUNICATING

11. DRAWBACKS
• Partitioned Database Architecture
• Have to settle for Eventual Consistency
• ACID transactions not possible
• Deploying
• Though scalable, but more complex
• Many more moving parts
• Service Discovery required

12. • Polyglot (Java, JavaScript, Groovy, Ruby, Python etc.)
• Event-driven & Non-blocking programming model
• Super simple Concurrency Model
• Lightweight ~ 650Kb
• “Ideal choice for creating light-weight, high-
performance, microservices”
• Public module repository
• Reactive applications
• Asynchronous APIs

13. CONCEPTS
• Event Loop
• Verticles
• Server Verticles
• Worker Verticles
• Event Bus
• Point to Point
• Pub/Sub
• Distributed

14. THE FAMOUS EVENT LOOP

15. ARCHITECTURE

16. • Don’t Block the Event Loop
• Workers “can” block
• Message Passing using Event Bus
• Concurrency Model
• A Verticle instance is always Single threaded
• No more Locking, synchronized & race conditions
• Actor-like concurrency model
• Scaling
• By Creating more Verticle Instances
• For TCP & HTTP servers, Vert.x does automatic load balancing
• Use FAT Jar for Deployment

17. VERT.X MODULES
• Core
• Web
• Data Access
• MongoDB, JDBC, Redis, MySQL
• Authentication Modules
• JWT, OAuth 2, JDBC Auth, Shiro Auth, MongoDB auth
• Messaging Systems
• Kafka, RabbitMQ
• Clustering – Hazelcast

18. VERT.X CORE
• Servers & clients
• TCP/SSL
• HTTP/HTTPS
• Websocket & SockJS
• EventBus
• Shared Maps & Sets
• Buffers & Flow Control
• Container API – Deploy & Undeploy Verticles
• Timers & Files
• Logging
• Configuration

19. VERT.X HTTP SERVER – HELLO WORLD

20. VERT.X WEB
• Routing
• Regex Matching
• Request Body Handling, parameters extraction
• Cookie Parsing & Handling
• Multipart Form & File Upload
• Session support ( sticky & non-sticky )
• CORS & CSRF Support
• Authentication & Authorization
• SockJS Support

21. VERT.X WEB HELLO WORLD

22. ROUTING

23. ROUTING
• Chain of Routers
• Either “end” it
• Or pass it to the “next” one
• Various Options – Route by
• HTTP Method Type
• Exact Path
• Regex Matching
• MIME type of request
• Decide Routing Order

24. VERT.X WEB
• BodyHandler
• Retrieve Request Body
• Limit Body Size
• Handle File Uploads
• CookieHandler
• Get, Add, Delete Cookie
• SessionHandler
• Sticky & Non-Sticky Sessions
• Vert.x don’t put actual data in Session Cookie – Session UUID is used to
lookup data on the server
• Session timeouts

25. VERT.X WEB
• Authentication & Authorization
• Support for Basic-Auth, Redirect-Auth, FormLogin
• JWT
• OAuth2
• Static Resources
• StaticHandler
• Caching – set headers ( cache-control, last-modified, date )
• Configurable webroot, index page
• Disable File Caching - .vertx
• Templating Support
• Handlebars, Jade, MVEL, Thymeleaf
• CORS & CSFR Handlers

26. DISTRIBUTED SUPPORT
DISTRIBUTED EVENT BUS
• Connect multiple Vert.x
instances across JVMs
• Event bus extends to client side
Javascript
• Ideal for “real-time” web
applications
• vertx-eventbus.js
CLUSTERING
• Hazelcast
• Shared Data Structures

27. REALTIME COMMUNICATION - SOCKJS
• Excellent Support for Low-latency, full-duplex cross-communication
channel
• Tries
• Native Websocket
• Browser specific transport protocols
• Polling for old browsers
• Heartbeats – prevent load balancers & proxies to close long running
http requests
• Vert.x – built in support for SockJS
• SockJS event bus bridge
• Distributed event bus
• Extend’s vert.x server side event bus to JavaScript clients
• vertx-eventbus.js – publish & register messages

28. APPLICATION PACKAGING
• Maven & Gradle Tooling Support
• Packaging
• Use maven-shade-plugin to package as FAT Jar
• Run the Jar

30. MESSAGE TYPES – EVENT BUS
• Primitives & their Boxed Types
• String
• org.vertx.java.core.json.JsonObject
• org.vertx.java.core.json.JsonArray
• org.vertx.java.core.buffer.Buffer
• Custom Type Support – Write your own Serializer

31. REAL-LIFE EXAMPLE - PULSE
• Marketing Cloud Core Service
• REST API for Notifications
• Vertx-Web powered Microservice

33. COMPARISONS
• Vert.x Vs Netty
• Application Vs Infrastructure
• Vert.x provides higher level IO
• Vert.x Vs Jetty
• Vert.x Vs NodeJS
• Use all available cores

34. VERT.X VS NODEJS
NodeJS vs Vert.x Performance

35. RESOURCES
• Nginx Microservices Introduction
• NodeJS Event Loop
• Interview with Tim Fox on Vert.x 3
• SockJS