SpringOne Platform 2017 Christoph Strobl, Pivotal; Mark Paluch, Pivotal "A huge theme in Spring Framework 5.0 and its ecosystem projects is the native reactive support that empowers you to build end-to-end reactive applications. Reactive data access especially requires a reactive infrastructure. But how is this one different from the ones used before? How does it deal with I/O? In this session, we will demystify what happens inside the driver and give you a better understanding of their capabilities. You will learn about the inner mechanics of reactive data access by walking through reactive drivers that are used in Spring Data."

1. Reactive Spring Data
Mark Paluch @mp911de
Christoph Strobl @stroblchristoph
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Spring Data Modules
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JPA

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Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
Reactive Spring Data Modules
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JPA

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7. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a
Creative Commons Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
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8. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a
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9. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a
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10. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a
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11. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
Today’s data access
• Keep resources busy
• Connection contention
• Usually synchronous/blocking
• Multiple requests
• Asynchronous isn’t always a good answer
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12. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
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Reactive data access
• Asynchronous
• Non Blocking
• Event Driven
• Data as stream
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13. Publisher
Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a
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Subscriber
Backpressure
Stream / Flow
Subscribe

14. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
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What it takes…
Project Reactor 3.1
Spring Framework 5.0
Spring Data 2.0
A reactive (asynchronous, ideally non-blocking) driver
Optional: Spring Boot 2.0 (Milestone)
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What about JDBC/JPA?
JDBC is a blocking API
JPA is a blocking API
Sorry, no reactive JPA support
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16. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
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Reactive Spring Data
Reactive Template API
Reactive Repository support
Reduced feature set
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17. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
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Imperative Template API
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<T> T insert(T objectToSave)
void insertAll(Collection<…> objects)
<T> List<T> find(Query query, Class<T> type)

18. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
Reactive Template API
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<T> Mono<T> insert(T objectToSave)
<T> Mono<T> insert(Mono<T> objects)
<T> Flux<T> find(Query query, Class<T> type)

19. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
Reactive Repository API
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interface ReactivePersonRepository extends
ReactiveCrudRepository<Person, String> {
Flux<Person> findByLastname(String lastname);
@Query("{ 'firstname': ?0 }")
Mono<Person> customQuery(String firstname);
Flux<Person> findByLastname(Mono<String> lastname);
}

20. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
Reactive Repository API
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interface ReactivePersonRepository extends
ReactiveCrudRepository<Person, String> {
Flux<Person> findByLastname(String lastname);
@Query("{ 'firstname': ?0 }")
Mono<Person> customQuery(String firstname);
Flux<Person> findByLastname(Mono<String> lastname);
}

21. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
Reactive Repository API
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interface ReactivePersonRepository extends
ReactiveCrudRepository<Person, String> {
Flux<Person> findByLastname(String lastname);
@Query("{ 'firstname': ?0 }")
Mono<Person> customQuery(String firstname);
Flux<Person> findByLastname(Mono<String> lastname);
}

22. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
Reactive Repository API
21
interface ReactivePersonRepository extends
ReactiveCrudRepository<Person, String> {
Flux<Person> findByLastname(String lastname);
@Query("{ 'firstname': ?0 }")
Mono<Person> customQuery(String firstname);
Flux<Person> findByLastname(Mono<String> lastname);
}

23. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
Reactive Repository API
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interface ReactivePersonRepository extends
RxJava2CrudRepository<Person, String> {
Flowable<Person> findByLastname(String lastname);
@Query("{ 'firstname': ?0 }")
Maybe<Person> customQuery(String firstname);
Single<Person> findByLastname(Mono<String> lastname);
}

24. Unless otherwise indicated, these slides are © 2013-2017 Pivotal Software, Inc. and licensed under a Creative Commons
Attribution-NonCommercial license: http://creativecommons.org/licenses/by-nc/3.0/
Reactive Repository API
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interface ReactivePersonRepository extends
RxJava2CrudRepository<Person, String> {
Flowable<Person> findByLastname(String lastname);
@Query("{ 'firstname': ?0 }")
Maybe<Person> customQuery(String firstname);
Single<Person> findByLastname(Mono<String> lastname);
}

25. Learn More. Stay Connected.
Spring Data Examples – Repository @ Github
WebFlux Example – Repository @ Github
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#springone@s1p

26. Disclaimer

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