Migrating Spring Boot to Quarkus, Challenge Accepted!

Many development teams using Spring Boot are evaluating Quarkus as an alternative. They come for the speed and they stay for the productivity. We will show an example of how to migrate the Spring Boot sample app, "Pet-Clinic" (REST), to Quarkus and how the lessons learned landed in the Migration Toolkit for Applications to make life easier for other developers doing this migration.

Transcript

1. Migrating
   QUARKUS
   

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2. Contents
   1. who are we?
   2. what can you expect?
   3. what is quarkus?
   4. why migrate?
   5. migration
   a. application description
   b. steps
   6. performance comparative
   7. references
   

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3. $ whoami
   @vilojona
   jvilalop@redhat.com
   aytartana.wordpress.com
   github.com/jonathanvila
   Java Champion
   JUG co-leader at BarcelonaJUG
   Co-founder of JBCNConf
   Software Engineer at Red Hat
   App. Modernisation and Migration team
   

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4. About:
   4
   Miguel Pérez Colino
   ● Product Manager for MTA
   ● ~9 years in Red Hat
   ○ Consultant (~3)
   ○ Solution Architect (~2)
   ● Technical Project Leader
   ● IT Architect
   ● Systems Engineer
   ● SysAdmin
   @mmmmmmpc
   ?
   

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5. What can you expect ?
   My experience
   v 2.2.5
   v 1.7.0
   opinionated option
   magistral lecture
   something that works
   THE way
   QUARKUS
   

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6. Quarkus brief description
   

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7. What is Quarkus ?
   A Kubernetes Native, Java, Scala, Kotlin stack
   tailored for GraalVM and OpenJDK HotSpot
   crafted from the best of breed Java libraries and standards.
   

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8. 300x faster 10x smaller focused on easy to code
   opensource fast paced releases tons of extensions
   Quarkus key facts
   

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9. Quarkus extensions ( > 90 )
   Kafka
   Camel
   Keycloak
   Spring
   Vert.x
   RestEasy
   ….
   Microprofile
   Openshift
   Jaegger
   Flyway
   Hibernate
   Infinispan
   ...
   

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10. Quarkus evolution
    2018-12 v 0.0.1
    2019-06 v 0.15.0
    2019-11 v 1.0.0 Release
    2020-01 v 1.2.0
    1 minor version every 2 weeks !!! (+/-)
    

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11. Quarkus performance
    

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12. Quarkus OSS status
    

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13. Migration
    

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14. Why to migrate
    My experience
    easy to develop with an easy CDI, REST, …
    long startup times, eternal tests
    heavyweight
    too many things happen under the hood
    easy to develop applications
    fast
    lightweight
    GraalVM compatible
    QUARKUS
    ✅ FaaS compatible ( lambdas )
    ✅ less money on public cloud
    

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15. Application migrated
    Spring Data ( repositories, jdbc , ... )
    Spring Web ( REST )
    Spring Security
    Spring documentation ( Swagger )
    Spring actuators
    Spring micrometer
    Spring CDI
    Spring AOP
    Spring cache
    Hibernate Panache
    JaxRS
    Quarkus Security
    OpenAPI
    SmallRye Health
    Microprofile Metrics
    CDI Spec ( Arc )
    ---
    Quarkus cache ( Caffeine )
    QUARKUS
    

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16. Elements not migrated
    Spring JDBC querying
    * no helper methods to work with Inserts, Updates….
    * no equivalent to org.springframework.jdbc.core classes
    * we need to reimplement everything using AGROAL
    JMX
    * not supported by GraalVM definition
    

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17. Migration Steps
    

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18. CDI
    ● Replace Autowired by Inject
    ● Beans declaration using @ApplicationScoped
    ● Auto injection on Constructors
    ● Lazy by default
    

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19. CDI
    PROs
    ● straight forward migration for Beans
    ● no feature missing
    ● we also can annotate the beans to be injected depending on
    the profile or a config property
    CONs
    ● no private members on injection
    

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20. JPA Repositories
    ● Repository classes to implement PanacheRepositoryBase
    Quarkus will generate the implementation of the usual methods :
    list , find, persist, delete
    

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21. JPA Repositories
    PROs
    ● straightforward migration
    CONs
    ● no Query DSL methods
    

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22. Spring REST to JAX-RS
    ● Move from Spring REST to the standard JAX-RS
    @RestController
    @RequestMapping, @GetMapping,
    @PostMapping, @PutMapping,
    @DeleteMapping
    @PathVariable
    @Path
    @GET,
    @POST, @PUT
    @DELETE
    @PathParam
    QUARKUS
    

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23. Spring REST to JAX-RS
    PROs
    ● straightforward migration
    INFO
    ● Spring also supports JAX-RS as 3rd party lib
    

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24. Spring REST Security to Quarkus Security
    ● replaced Spring REST Security
    

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25. Spring REST JDBC Security to Elytron JDBC realm
    Add extension dependency : elytron-security-jdbc
    Configure on properties file and remove configureGlobal method
    

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26. Spring REST Security to Quarkus security
    PROs
    ● Almost the same result
    ● By configuration rather than code
    CONs
    ● Quarkus doesn’t have an expression language
    

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27. CORS
    ● configured CORS in the application.properties file
    

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28. CORS
    PROs
    ● easy to enable , no code involved
    CONs
    ● at global level, not per Controller
    

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29. Metrics
    ● Add smallRye metrics extension
    ● Annotate each method ( for custom metrics )
    Micrometer compatibility
    quarkus.smallrye-metrics.micrometer.compatibility=true
    

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30. Metrics
    PROs
    ● OpenMetrics standard naming or Micrometer,
    you choose
    ● You can even use Micrometer extension
    CONs
    ● no AOP so you need to annotate every
    method
    

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31. Validation
    ● Spring Validation to Hibernate Validator
    ● Move from @ControllerAdvice to JAX-RS ExceptionMapper
    

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32. Validation
    PROs
    ● standard
    ● easy
    CONs
    ● none
    

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33. Swagger ( OpenAPI v 3.0 )
    ● Add extension “openapi”
    ● extend Application
    

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34. Swagger ( OpenAPI v 3.0 )
    PROs
    ● straightforward migration
    ● standard and easy way to configure
    ● Swagger-UI OOTB
    CONs
    ● not REST paths scan configuration
    

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35. AOP for app metrics
    ● use of microprofile metrics annotations
    

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36. AOP for repository metrics
    ● using Hibernate built in metrics enabled in properties
    

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37. AOP for app metrics
    PROs
    ● standard
    ● easy to customise
    CONs
    ● need to annotate ALL methods one by one for
    custom app metrics
    ● no expression language to define methods affected
    

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38. Local caching
    ● Spring uses a default ConcurrentHashMap
    ● Caffeine uses a ConcurrentLinkedHashMap
    ● Add “cache” extension ( Caffeine ) and annotate the method
    

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39. Local Caching
    PROs
    ● easy to implement and configure
    ● straightforward migration
    CONs
    ● none
    

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40. Test : REST
    MockMVC -> RestAssured
    

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41. Test REST
    PROs
    ● RESTassured is easy to handle and very intuitive
    CONs
    ● No way to simulate Roles without creating an user for each role to test
    INFO
    ● Changed JSonPath to GPath
    

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42. Test - resources
    ● Annotate test suites with @QuarkusTest to boot the app
    ● Annotate test suites with @QuarkusTestResource to load an embedded
    resource
    

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43. Test - Mock
    ● Use the quarkus-mockito dependency : quarkus-junit5-mockito
    ● Annotate mocks with @InjectMock
    

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44. Spring API in Quarkus
    

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45. Spring WEB ( REST) : spring-web extension
    Using same Spring API for REST Supported Annotations
    @RestController
    @RequestMapping
    @GetMapping
    @PostMapping
    @PutMapping
    @DeleteMapping
    @PatchMapping
    @RequestParam
    @RequestHeader
    @MatrixVariable
    @PathVariable
    @CookieValue
    @RequestBody
    @ResponseStatus
    @ExceptionHandler
    

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46. Spring DI : spring-di extension
    Using same API as Spring DI
    Annotations Supported
    @Autowired @Repository
    @Qualifier @Scope
    @Value @Component
    * doesn’t support an expression language
    @Configuration @Service
    @Bean
    

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47. Spring Data : spring-data-jpa
    Using same API for Spring Data Supported
    Any interface of : Repository,
    CrudRepository, PagingAndSortingRepository,
    JpaRepository
    Derived Query Methods
    User defined Queries
    Not Supported
    Invocations to any method of
    QueryByExampleExecutor
    QueryDSL
    

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48. Spring Security: spring-security extension
    Using same API as Spring Security
    Annotations Supported
    @Secured
    @Preauthorized
    Expressions allowed
    hasAnyRole
    permitAll
    denyAll
    isAnonymous
    isAuthenticated
    #paramName ==
    

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49. Performance comparative (shallow)
    SPRING BOOT
    2.2.5
    QUARKUS
    Hotspot 1.8
    QUARKUS
    GraalVM 20.1
    build
    ( uber-jar )
    4.3 s
    48 Mb
    13 s
    42 Mb
    185 s
    97 Mb
    boot 6.8 s
    630 Mb
    2.6 s ( 3x )
    251 Mb ( 2.5x )
    0.462 s ( 15x )
    21 Mb ( 30x )
    

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50. References
    

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51. Repositories
    ● Spring REST PetClinic
    https://github.com/spring-petclinic/spring-petclinic-rest
    ● Quarkus REST PetClinic
    https://github.com/jonathanvila/spring-petclinic-rest/tree/quarkus
    Documentation/News/Help
    ● https://quarkus.io
    ● @QuarkusIO
    ● https://developers.redhat.com/search/?t=quarkus
    ● quarkus-dev@googlegroups.com
    

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52. Interactive Tutorials ( Katacoda )
    ● https://developers.redhat.com/courses/quarkus/
    List of Tutorials
    ● Getting Started
    ● For Spring Devs
    ● Streaming with
    Kafka
    ● Hibernate and
    Panache
    ● Prometeus &
    Grafana
    

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53. Cheat Sheet
    ● https://lordofthejars.github.io/quarkus-cheat-sheet/
    by Alex Soto
    

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54. Do you want to start coding with Quarkus ?
    https://code.quarkus.io/
    

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55. Migration Toolkit for Applications by Red Hat (MTA)
    New Web Console UI with Patternfly 4 (v 5.1.0)
    

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56. Migration Toolkit for Applications by Red Hat (MTA)
    Review rules new interface in 5.1.0
    

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57. ● Rules to help to migrate from SB to Quarkus ( MTA 5.1.0 )
    ○ Open Source tool to help on applications migrations
    ■ https://red.ht/mta
    ■ https://github.com/windup
    ○ 24 rules , covering ...
    ■ DI
    ■ Integration
    ■ Metrics
    ■ JPA
    ■ Security
    ■ Web
    ■ Shell
    ■ ….
    Migration Toolkit for Applications by Red Hat (MTA)
    

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58. Migration Toolkit for Applications by Red Hat (MTA)
    Spring Boot to Quarkus output example
    

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59. Migration Toolkit for Applications by Red Hat (MTA)
    IDE Integration
    Eclipse / VS Code / Eclipse Che
    

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60. Migration Toolkit for Applications by Red Hat (MTA)
    OpenShift Operator (v 5.1.0)
    

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61. Real use cases
    Lufthansa Technik AVIATAR experiences significant cloud resources
    savings by moving to Kubernetes-native Quarkus (link)
    Suomen Asiakastieto Oy chooses Quarkus for their microservices
    development (link)
    Vodafone Greece replaces Spring Boot with Quarkus (link)
    ● “Quarkus offers by default (without trying to optimize it) is 50%-60% more
    lightweight (in JVM mode) that what Spring offers”
    ● “30 to 40% better developer productivity vis-a-vis Spring Boot,”
    Public Clouds exp.
    -- Internal Labs ---
    Save up to :
    ● 37 % on Cloud ( Quarkus JVM )
    ● 71 % on Cloud ( Quarkus + GraalVM )
    

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62. @vilojona
    jvilalop@redhat.com
    aytartana.wordpress.com
    github.com/jonathanvila
    Thank you :)
    @mmmmmmpc
    miguel@redhat.com
    https://developers.redhat.com/blog/
    author/miguel/
    github.com/mpereco
    

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63. Questions received on meetups ( 1/3 )
    1. What do the spring extensions do internally ?
    2. Those quarkus extensions for libraries are like a fork of the general library ?
    3. General library and quarkus extension will be always on sync on versions ?
    4. What about the patches on the general library and the impact on quarkus extension ?
    5. Have you tried compiling the bytecode with Graal ? [I assume this means the bytecode generated by the Spring version]
    a. Yes, but I didn’t succeed . I assume there are a lot of things to do and elements to take into consideration (libraries not supported)
    6. Do you recommend to always migrate from Spring ?
    a. NO
    b. migration means investing money and time, so the goal has to be clear. Benefit is great when you have microservices with scale to
    zero as common, or when you can consider moving to Serverless/FaaS (lambdas)
    7. Using the spring extensions would have same performace as pure quarkus ?
    8. How many redhatters in the project ?
    a. Currently there are more than 360 contributors, and lot’s of redhatters but also non redhatters.
    9. Is there an Elytron LDAP extension for security ?
    a. YES : https://quarkus.io/guides/security-ldap
    

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64. Questions received on meetups ( 2/3 )
    10. How would the Quarkus support work ?
    a. https://quarkus.io/support/
    11. AOP on JVM ?
    a. NO
    b. because AspectJ needs to add the plugin to wave the classes on the build phase, and this conflicts with the same
    Quarkus plugin
    12. Company using Quarkus in native mode in production ?
    13. Porting websockets to Quarkus ?
    14. Quarkus native throughput degradation ?
    a. basically related to the GraalVM way of working with AOT compilation
    b. switch to g1gc in native images, profile guided optimizations ( GraalVM Enterprise )
    15. Hibernate metrics affect performance ?
    16. Is it possible to run Quarkus inside EAP ?
    17. Does Quarkus have enterprise support ?
    a. YES
    b. https://quarkus.io/support/
    18. Difference between Hotspot and GraalVM
    a. hotspot mean the JVM, so you need a Virtual Machine installed to run the app
    b. graalvm will produce native code applications that don’t need any vm installed
    

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65. Questions received on meetups ( 3/3 )
    19. When to migrate ?
    a. see question #6
    20. Benefits of Quarkus vs Micronaut
    a. both are good technologies, with different flavour, covering a space of the optimized native applications
    b. you need to read and try both and decide based on your own criteria
    21. Can SB compile to native with GraalVM ?
    a. they are working on that
    b. they have projects being able to go native in the labs/experimental repos
    22. Does MTA/Windup use AI ?
    a. NO
    b. it statically analyses applications based on rules , mainly defined on xml files that you can create yours rules
    23. How to migrate from EAP to Quarkus
    24. In a migration what do you recommend , going to the standard libraries or using the spring extensions ?
    25. Is Spring Kafka supported ?
    26. Is there a way to debug a GraalVM compiled application ?
    27. Are there many companies adopting Quarkus ?
    28. How easy is to produce the native image ?
    29. How easy is to deploy to cloud ?
    

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