Grails 3 Preview

Talk by Graeme Rocher on the future of the Grails framework and upcoming 3.0 version

1. © 2014 SpringOne 2GX. All rights reserved. Do not distribute without permission. Grails 3.0 Preview By Graeme Rocher
2. Agenda § State of Nation § What’s planned for Grails 2.4? § What’s planned for Grails 3.0? § Summary / Q & A
3. State of Nation § Grails 2.4.3 most recent version § Grails 2.3.x line at 2.3.9 § Hundreds of bugs fixed in the last 3 months § More than 1,100 plugins now for Grails
4. ! Grails 2.4 What’s new? 2.4
5. Grails 2.4 • Spring 4.0 Upgrade • Java 8 Support • Groovy 2.3 Upgrade • Improved @CompileStatic Support • Asset Pipeline Plugin • Moduralization of Codebase • Hibernate Goodies • GORM & GSP Standalone 5 3.0 2.4
6. Spring 4.0 / 4.1 • Native GroovyBeanDefinitionReader (ported from BeanBuilder) – https://spring.io/blog/2014/03/03/groovy- bean-configuration-in-spring-framework-4 • Spring Web Socket – http://grails.org/plugin/spring-websocket 6
7. Groovy 2.3 • Traits • Java 8 • Implicit closure coercion • Lots more! • http://docs.codehaus.org/ display/GROOVY/Groovy +2.3+release+notes 7
8. Other Notable Updates • Java 8 Support • Hibernate 4.3.5 now default • AspectJ 1.8 with Java 8 support • Eclipse Aether 1.0.0 • Fewer Overall Dependencies 8
9. Modularization 9 grails-web grails-web-mvc grails-web-sitemesh grails-web-gsp grails-web-jsp grails-web-servlet grails-web-common grails-core grails-encoder grails-project-api grails-validation
10. Asset Pipeline Plugin • Resources replaced with Asset Pipeline – https://github.com/bertramdev/asset- pipeline/wiki/Why-asset-pipeline-over- grails-resources-plugin • Full documentation – http://bertramdev.github.io/asset- pipeline/ • Many thanks to David Estes! 10
11. Standalone • GORM for Hibernate 4 in Spring Boot – https://spring.io/guides/gs/accessing-data-gorm/ • GORM for MongoDB in Spring Boot – https://spring.io/guides/gs/accessing-data-gorm-mongodb/ • GSP standalone – https://github.com/grails/grails-boot/tree/master/sample-apps/ gsp 11
12. @GrailsCompileStatic • Grails-aware version of Groovy’s @CompileStatic 12 import  grails.compiler.*   ! @GrailsCompileStatic   class  BookController  {     …   }
13. Maven-style Dependency Management • Use management block to declare managed dependencies 13 ! management  {      dependency  "commons-­‐logging:commons-­‐ logging:1.1.3"   }
14. Hibernate Subqueries • Perform nested “in” or “notIn” sub queries that span domain classes using where queries: 14 def  employees  =  Employee.where  {          region.continent  in  ['APAC',  "EMEA"]   }.id()   ! def  results  =  Sale.where  {        employee  in  employees  &&  total  >  50000   }.employee.list()
15. Hibernate Correlated Subqueries • Declare aliases using “def” for cross query references: 15 def  query  =  Employee.where  {          def  em1  =  Employee          exists  Sale.where  {                  def  s1  =  Sale                  def  em2  =  employee                  return  em2.id  ==  em1.id          }.id()   }   def  results  =  query.list()
16. Hibernate Column Readers/Writers • Implement custom column readers and writers to transform data when written or read from the database. 16 class  Name  {          String  title          static  mapping  =  {                  title  write:'UPPER(?)',                            read:'REPEAT(title,  2)'          }   }
17. Hibernate 4 in Unit Tests (Coming Soon) • Test Hibernate 4 interaction in unit tests 17 import  grails.test.mixin.hibernate.*   ! @TestMixin(HibernateTestMixin)   class  PersonSpec  extends  Specification{          void  setupSpec()  {                  hibernateDomain([Person])          }        …   }
18. GORM for MongoDB 3.0 • Support for MongoDB 2.6 • GeoJSON type support • Maps of entities • Full Text Search • Projections using Aggregations • Size queries (sizeEq, sizeLt etc.) • Spring Boot – https://spring.io/guides/gs/accessing- data-gorm-mongodb/ 18
19. New Maven Plugin 2.4.3 • Upgraded to Maven 3.1+ • Rewritten to use Aether for dependency resolution as per recommendations • Can now be used with multiple versions of Grails: 19 <configuration>        <grailsVersion>2.3.8</grailsVersion>   </configuration>  
20. Grails 2.4.x TODOs • Grails 2.4.4 - Out Soon • Spring Security Core 2.0 GA • Spring Web Flow Plugin Update • Bug Fixes 20 2.4
21. ! Q & A Grails 2.4 2.4
22. ! The Future Grails 3.0 3.0
23. Grails 3.0: Goals • Embrace Gradle • Abstract Packaging / Deployment • Reach outside the Servlet Container • App Profiles: Netty, Servlet, Batch, Hadoop • Deployment with run-app / runnable JARs • Extend the reach of Grails 23 3.0 3.0
24. Grails 3.0: Goals • Build on Spring Boot • Plugin System & Events • Support Multi Project Builds • Support Micro Services • Remove Bloat • Reduce Dependencies 24 3.0 3.0
25. Spring IO Platform Reprise 25 Jobs, Steps,
 Ingestion, Export,
 Controllers, REST, Channels, Adapters,
 WEB INTEGRATION BATCH BIG DATA SPRING CORE FRAMEWOR SECURIT GROOV REACTO DATA RELATIONA NON- BOOT Bootable, Minimal, Ops-Ready GRAILS XD IO IO
26. Spring IO Platform 26 Grails Spring IO Platform Spring XD Spring Foundation Apps 3rd Party Dependencies Spring Boot
27. Spring IO & Grails • What does Spring IO bring to Grails? – Standardised dependency management – Published BOMs for use with Maven & Gradle – Foundational libraries – See more http://docs.spring.io/platform/docs/current/ reference/htmlsingle/ 27 dependencies  {          compile  'commons-­‐lang:commons-­‐lang'   }
28. Gradle • Deprecate existing build system • Replace with Gradle build • Easier now everything is forked in 2.3.x • All the flexibility of a powerful build system • Separate build plugins can provide Gradle extensions 28
29. Plugin Delineation 29 Grails.sh Static void main Gradle Build Forked Grails Runtime test-app shell run-app console Codegen Plugins Build Time Plugins Runtime Plugins
30. Gradle • Allow Micro or Monolith Applications • Multi-Project Plugin Architectures • Run individual sub projects • Or run as a whole 30
31. ! Demo Grails 3.0 
 Gradle 3.0
32. Spring Boot • Grails 3.0 to be built on Spring Boot • Boot to handle • Embedded servers • Runnable JARs • WAR packaging • Scripting / Micro Services 32
33. Why Spring Boot? • Handles Fat JAR and embedding • Already supports different runtimes • Includes monitoring and health 
 checks • Grails can take advantage of Boot
 auto configuration 33
34. Boot Powered Micro Services 34 @Grab("com.h2database:h2:1.3.173")   import  grails.persistence.*   ! @Entity   @Resource(uri='/books')   class  Book  {          String  title   }  
35. ! Demo Grails 3.0 
 Micro Services 3.0
36. Deprecations / Removals • Servlet 2.5 support (no web.xml) • Gant & Current Build System • GDoc - Replaced by AsciiDoctor • Integration Tests - Replaced by more Mixins • Converters / Codecs plugins - Replaced by Groovy extensions • Filters - Replaced by new mechanism 36
37. Servlet 3.0 only and no web.xml • Thanks to Spring Boot, new servlets and filters can just be Spring beans 37 ! def  doWithSpring  =  {          characterEncodingFilter(                    CharacterEncodingFilter)  {                          encoding  ='utf-­‐8'          }   }
38. Simplification • Removed – UrlMappingsFilter – GrailsDispatcherServlet – SimpleGrailsController – Sitemesh Filter 38
39. Old Grails 2.x Flow 39 UrlMappingsFilter GrailsPageFilter Decorate Request Forward Request GrailsDispatherServlet Delegate Request GrailsController
40. Grails 3.0 Flow • GrailsDispatcherSerlvet 50 lines of code in 3.x, 
 but 545 lines in 2.x 40 DispatcherServlet Delegate Request GrailsController
41. Benefits of Simplification • Less code to maintain • Better performance • Better integration with Spring • Fewer dependencies • commons-fileupload gone • No internal forwarding 41
42. Evolution of Metaprogramming 42 Runtime
 Metaprogramming
 (ExpandoMetaClass) Compile time
 Metaprogramming
 (AST Transforms) Traits & 
 Transforms Grails 1.x Grails 2.x Grails 3.x
43. Grails 3.0 & Groovy Traits • Most logic previously added via AST transforms will now be added by Traits – (Cases not possible as Trait done with transforms) 43 trait  Controller  {      …      def  withFormat(Closure  callable)  {            …      }   }
44. Application Profiles • Each profile will have distinct plugins, runtimes and packaging (JAR, WAR etc.) 44 ! $  grails  create-­‐app  myapp  -­‐-­‐profile=netty     $  cd  myapp   $  grails  package   $  java  -­‐jar  target/myapp.jar   !
45. Application Profiles • Extensible profiles with an API exposing structure • Profile specific commands (run, package, test) • Profile specific plugins • Profile specific project templates and file templates (code generators) backed by Git • Community maintained profiles and core profiles 45
46. Profile Repository • All Profiles managed by git • Profiles checked out locally and periodically updated • Profiles wrap code generation infrastructure 46 $  grails  create-­‐controller  foo   ! Profile
  .getCurrentProfile()
  .getCommand('create-­‐controller')
  .execute(  'foo'  )
47. Grails 3.0: Challenges • Compatibility – Plugins – Build System • Modularization – Servlet API independence – Refactoring 47 3.0
48. ! Q & A Grails 3.0 3.0
49. Stay Connected. ! ! ! ! Web: grails.org StackOverflow: http://stackoverflow.com/tags/grails Twitter: twitter.com/grailsframework LinkedIn: http://linkedin.com/groups/Grails-User-Group-39757 Google+: https://plus.google.com/communities/ 109558563916416343008