1. autodiscoverable microservices with vertx3
Andy Moncsek

2. About me Andy Moncsek Senior Consultant Application development
Trivadis AG Switzerland

3. Agenda about microservices Vert.x 3 introductionH F I
about microservices
Vert.x 3 introduction
microservices on top of Vert.x 3

4. C E B A G H F I
about microservices

5. characteristics of microservices [1 Martin Fowler]
component oriented, replaceable, independent
focus on business capabilities
UNIX style: do one thing well & work together
smart endpoint & dump pipes (no ESB ;-) )
distributed / decentralized data
1 Martin Fowler : A E F G C H B I

6. microservice design patterns
Architecture patterns
Router/Aggregator/Chained/shared-data
Deployment patterns
instance per host, VM, Container
be aware of different depl. patterns
Req.-Resp.: response expected, need to know who to ask; Pub-Sub. : service registers itself
Events (order 123 created), Queries/Commands : what should happen A E F G C H B I

7. microservice design patterns
Interaction/communication pattern
Request-Reply vs. Pub-Sub / Events vs. Queries/Commands
Service discovery
serverside/clientside-discovery / self-/3d-party- registration
be aware of different depl. patterns
Req.-Resp.: response expected, need to know who to ask; Pub-Sub. : service registers itself
Events (order 123 created), Queries/Commands : what should happen A E F G C H B I

8. C E B A G H F I
Vert.x 3

9. Vert.X 3 (tool-kit for building reactive applications)
nodeJS for Java developers :-D (sorry Tim)
event driven / non blocking
polyglot (written in Java 8)
general purpose (web, backend)
current version: v3.0-milestone6

10. Vert.X 3 (terms) Vert.X Verticle Event Bus Eventloop vs. Worker F E A
1: The runtime env. either as binary dist. , embedded, fat-jar
2: Verticles are chunks of code that get deployed and run by Vert.x
3: connects all parts of your application (Verticles) / clusterable (Hazlecast)
4: default: Event Loop single threaded - Don’t block the event loop! / Worker Verticles A E F G C H B I

11. Vert.X 3 (terms) Scaling, Cluster / HA VerticleFactory packaging
TCP, UDP, HTTP, WebSocket, SocketJS, FileSystem,…..
1: define number of instances (1 thread/instance), Clustering: „EventBus over network“, HA: failover
2: VerticleFactory: SPI to extend Vert.x (different languages, Spring)
3: no custom modules anymore (simple maven & maven-shade-plugin)
4: create … A E F G C H B I

12. C E B A G H F I
DEMO
Vert.x 3

13. microservices on top of Vert.x 3B A G H F I
microservices on top of Vert.x 3

14. Vert.X microservice framework
current status: working prototype!
idea: all-in-one microservice framework based on Vert.X
components:
service Verticle
service router / API gateway
service registry / heartbeat
service discovery A E F G C H B I

15. Vert.X microservice framework - service Verticle
@ApplicationPath("/articleService")
Verticle
@Path("/comments/:id")
@OperationType(Type.REST_GET)
final String id, Message m)
classical „jersey-style“ Path + method vs. async handler registration
Why? „reactive / event-driven“ is cool but for many developers still „neuland“
classical input/output (method with parameter and return type) is not applicable (it blocks!)… solution message reply handler
@Path("/fetchByArticleIdWS")
@OperationType(Type.WEBSOCKET)
fetchByArticleIdWS(String id, WSMessageReply r)
desc.
@Path("/fetchByArticleId")
@OperationType(Type.EVENTBUS)
fetchByArticleId(String id, EBMessageReply r)

16. Vert.X microservice framework - router / gateway
client
router /gateway host:port
@Path("/articleService/comments/:id")
@Path(„/../fetchByArticleIdWS")
@Path(„/..byArticleId“)
service
Event Bus
Vert.X cluster

17. Vert.X microservice framework - registry / heartbeat
challenge: many verticles instances (lokal and cluster)
needs to synchronize registration process on startup…
solution: cluster-wide counter
challenge registry: clusterWideMap is not iterate able…
solution: key is the router-key, value is a blob of a descriptor object with all registered descriptions
generally figure out how dropwizard is usable for heartbeat
router /gateway host:port
ping
register
unreg.
registry
register
Vert.X cluster

18. Vert.X microservice framework - discovery
router /gatew ay host:po rt
regis try
discovery.service(„name“, op-> );
client / server API the same
connects through vertx instance or REST-URL
op.operation(„path“, p-> )
fail
p.eventBusSend(„message",r->{
// reply
});
fail
Vert.X cluster

19. Vert.x microservice frameworkB A G H F I
DEMO
Vert.x microservice framework

20. C E B A G H F I
any questions?

21. C E B A G H F I
Thank you

22. [1] http://www.infoq.com/news/2014/11/gotober-fowler- microservices
[2] bien.com/roller/abien/entry/the_perfect_javaee_microser vice
[3] versus-autonomy-in-microservices/
[4] design-patterns/