Microservicios con Kotlin y MicroProfile

En esta presentación exploramos el uso de Kotlin en el contexto de Java EE y MicroProfile, mezclando la estabilidad de estandares de 20 años ampliamente aceptados por la industria, con la innovación de un lenguaje JVM de popularidad reciente.

Transcript

1. Ense˜ nando trucos de 20 a˜ nos a Kotlin V´ ıctor Orozco 30 de mayo de 2019 @tuxtor 1
2. Kotlin
3. Kotlin • Tipado est´ atico y compilado • Java inter-op • OO + FP • Null safety • Extensions • Operator overloading • Data classes • One line methods 2
4. Kotlin - Datos interesantes • Effective Java - Inmutabilidad, builder, singleton, override, final by default, variance by generics • Elvis - Groovy • Inferencia de tipos - Scala • Inmutabilidad - Scala • Declaraci´ on de variables - Scala • Manejo de Null - Groovy • Closures y funciones - Groovy • Google 3
5. Java - Muriendo desde 1995 • Sistemas legados (IBM) • Retrocompatibilidad • Release cadence (6 meses) • Innovaci´ on constante en el ecosistema (Spring Boot, Micronaut, MicroProfile, GraalVM) • Raw performance (Beam, Spark, Hadoop) • Tooling - IDE, Maven, Drivers RDBMS • JVM - (Twitter, Alibaba) • OpenJDK 4
6. Java - Muriendo desde 1995 5
7. Java - Muriendo desde 1995 6
8. ¿Microservicios?
9. Reactive applications Aplicaciones reactivas Microservicios son una (de muchas) herramienta para creaci´ on de aplicaciones reactivas 7
10. Microservicios Figura 1: Microservicios 8
11. Microservicios - Java • DIY - Jooby, Javalin, Micronaut, Spark, Vert.x, Helidon SE • Enterprise - Spring Boot, Microprofile (implementaciones) 9
12. Microservicios - Kotlin • DIY - Jooby, Javalin, Micronaut, Spark, Vert.x, Helidon SE, Ktor • Enterprise - Spring Boot, Microprofile (implementaciones) 10
14. Jakarta EE 8
15. Jakarta EE 8 12
16. Jakarta EE 8 - Comunidad Java EE 13
17. Eclipse MicroProfile
18. Eclipse MicroProfile Figura 2: Credito: Reza Rahman 14
19. Eclipse MicroProfile 15
20. Eclipse MicroProfile 16
21. Eclipse MicroProfile - Implementaciones Bibliotecas • SmallRye (Red Hat) • Hammock • Apache Geronimo • Fujitsu Launcher JEAS - Fat Jar, Uber Jar • Dropwizard • KumuluzEE • Helidon (Oracle) • Open Liberty (IBM) • Apache Meecrowave • Thorntail (Red Hat) • Quarkus (Red Hat) • Payara Micro 17
22. Eclipse MicroProfile - Implementaciones Micro server - Thin War • Payara Micro • TomEE JAX-RS Full server • Payara Application Server • JBoss Application Server / Wildfly Application Server • WebSphere Liberty (IBM) https://wiki.eclipse.org/MicroProfile/Implementation 18
23. Eclipse MicroProfile + Kotlin + Maven
24. Eclipse MicroProfile en Payara 5 <dependency > <groupId >org.eclipse.microprofile </ groupId > <artifactId >microprofile </ artifactId > <type >pom </type > <version >2.0.1 </ version > <scope >provided </scope > </dependency > 19
25. Kotlin en Maven - Dependencias <dependency > <groupId >org.jetbrains.kotlin </groupId > <artifactId >kotlin -stdlib -jdk8 </artifactId > <version >${ kotlin.version}</version > </dependency > 20
26. Kotlin en Maven - maven-compiler-plugin <execution > <id >default -compile </id > <phase >none </phase > </execution > <execution > <id >default -testCompile </id > <phase >none </phase > </execution > <execution > <id >java -compile </id > <phase >compile </phase > <goals > <goal >compile </goal > </goals > </execution > <execution > <id >java -test -compile </id > <phase >test -compile </phase > <goals > <goal >testCompile </goal > </goals > </execution > 21
27. Kotlin en Maven - kotlin-maven-plugin <c o m p i l e r P l u g i n s> <plugin>a l l −open</plugin> </c o m p i l e r P l u g i n s> . . . <option>a l l −open : annotation=j av a x . ws . r s . Path</option> <option>a l l −open : annotation=j av a x . e n t e r p r i s e . context . RequestScoped</option> <option>a l l −open : annotation=j av a x . e n t e r p r i s e . context . SessionScoped </option> <option>a l l −open : annotation=j av a x . e n t e r p r i s e . context . ApplicationScoped </option> <option>a l l −open : annotation=j av a x . e n t e r p r i s e . context . Dependent</option> <option>a l l −open : annotation=j av a x . e j b . Singleton </option> <option>a l l −open : annotation=j av a x . e j b . S t a t e f u l </option> <option>a l l −open : annotation=j av a x . e j b . S t a t e l e s s </option> 22
28. Demo
29. Kotlin + Jakarta EE + MicroProfile - Demo • Kotlin 1.3 • Bibliotecas externas - SL4J, Flyway, PostgreSQL • Jakarta EE 8 - EJB, JPA • MicroProfile - CDI, JAX-RS, MicroProfile config • Testing - Arquillian, JUnit, Payara Embedded https://dzone.com/articles/ the-state-of-kotlin-for-jakarta-eemicroprofile-tra https://github.com/tuxtor/integrum-ee 23
30. Kotlin + Jakarta EE + MicroProfile - Demo 24
31. Kotlin + Jakarta EE + MicroProfile - Demo 25
32. Kotlin - Entidad JPA @Entity @Table(name = "adm_phrase") @TableGenerator (...) data class AdmPhrase( @Id @GeneratedValue (strategy = GenerationType .TABLE , generator = " admPhraseIdGenerator ") @Column(name = "phrase_id") var phraseId:Long? = null , var author:String = "", var phrase:String = "" ) Data Clases, Nullable Types 26
33. Kotlin - Repositorio CDI @RequestScoped class AdmPhraseRepository { @Inject private lateinit var em:EntityManager ... } Lateinit (nullable type) 27
34. Kotlin - Repositorio CDI fun create(admPhrase:AdmPhrase) = em.persist(admPhrase) fun update(admPhrase:AdmPhrase) = em.merge(admPhrase) fun findById(phraseId: Long) = em.find(AdmPhrase :: class.java , phraseId) fun delete(admPhrase: AdmPhrase) = em.remove(admPhrase) . . . Single expression functions (One line methods) 28
35. Kotlin - Repositorio CDI fun listAll(author: String , phrase: String ): List <AdmPhrase > { val query = """SELECT p FROM AdmPhrase p where p.author LIKE :author and p.phrase LIKE :phrase """ return em.createQuery(query , AdmPhrase :: class.java) .setParameter("author", " %$author %") .setParameter("phrase", " %$phrase %") .resultList } Multiline String, mutable declaration 29
36. Kotlin - Controlador JAX-RS @Path ( "/phrases" ) @Produces ( MediaType . APPLICATION JSON) @Consumes ( MediaType . APPLICATION JSON) c l a s s AdmPhraseController { @Inject p r i v a t e l a t e i n i t var admPhraseRepository : AdmPhraseReposit @Inject p r i v a t e l a t e i n i t var l o g g e r : Logger . . . } 30
37. Kotlin - Controlador JAX-RS @GET fun f i n d A l l ( @QueryParam ( "author" ) @DefaultValue ( " %" ) author : String , @QueryParam ( "phrase" ) @DefaultValue ( " %" ) phrase : S t r i n g ) = admPhraseRepository . l i s t A l l ( author , phrase ) @GET @Path ( "/{id :[0 -9][0 -9]*}" ) fun f i n d B y I d ( @PathParam ( "id" ) i d : Long ) = admPhraseRepository . f i n d B y I d ( i d ) @PUT fun c r e a t e ( phrase : AdmPhrase ) : Response { admPhraseRepository . c r e a t e ( phrase ) return Response . ok ( ) . b u i l d () } 31
38. Kotlin - Controlador JAX-RS @POST @Path ( "/{id :[0 -9][0 -9]*}" ) fun update ( @PathParam ( "id" ) i d : Long ? , phrase : AdmPhrase ) : Response { i f ( i d != phrase . p h r a s e I d ) return Response . s t a t u s ( Response . Status .NOT FOUND) . v a l updatedEntity = admPhraseRepository . update ( phrase ) return Response . ok ( updatedEntity ) . b u i l d ( ) } @DELETE @Path ( "/{id :[0 -9][0 -9]*}" ) fun d e l e t e ( @PathParam ( "id" ) i d : Long ) : Response { v a l updatedEntity = admPhraseRepository . f i n d B y I d ( i d ) ? : return Response . s t a t u s ( Response . Status .NOT FOUND) . b u i l d () admPhraseRepository . d e l e t e ( updatedEntity ) return Response . ok ( ) . b u i l d () } Elvis operator as expression 32
39. 12 factores cloud native (Heroku) Microprofile • Config • Backing service • Disposability Cloud • Codebase (Git-Flow) • Dependencies (Maven) • Build, Release, Run • Processes (Pipelines) • Port binding • Concurrency (Docker - k8s) • Dev / Prod parity • Logs • Admin process 33
40. Oracle Cloud <groupId>i o . f a b r i c 8</ groupId> <a r t i f a c t I d>docker−maven−p l u g i n</ a r t i f a c t I d> <version>0 . 3 0 . 0</version> . . . <image> <name>i a d . o c i r . i o / t u x t o r / m i c r o p r o f i l e / integrum−ee</name> <b u i l d> <d o c k e r F i l e>${ p r o j e c t . b a s e d i r }/ D o c k e r f i l e</ d o c k e r F </ b u i l d> </image> 34
41. Oracle Cloud 35
42. Oracle Cloud 36
43. Oracle Cloud 37
44. Oracle Cloud 38
45. Kotlin Ventajas • C´ odigo m´ as conciso • Soporte real Java inter-op • Aprovechar a personal Android para backend • Un lenguaje para dominar todo Desventajas • IntelliJ IDEA Ultimate (monolitos) • Requiere mejores programadores (m´ as convenciones) • Tiempo de compilaci´ on • No es una buena idea utilizar corutinas en entornos con managed threads 39
46. V´ ıctor Orozco • vorozco@nabenik.com • @tuxtor • http://www.nabenik.com This work is licensed under a Creative Commons Attribution-ShareAlike 3.0. 40