Grails 3.0 Preview

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Grails 3.0 PreviewBy Graeme Rocher

Agenda

§ State of Nation § What’s planned for Grails 2.4? § What’s planned for Grails 3.0? § Summary / Q & A

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

!Grails 2.4What’s new?

2.4

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

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3.02.4

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

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Groovy 2.3

• Traits • Java 8 • Implicit closure coercion • Lots more!

• http://docs.codehaus.org/display/GROOVY/Groovy+2.3+release+notes

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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

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Modularization

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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

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!

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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

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@GrailsCompileStatic• Grails-aware version of Groovy’s @CompileStatic

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import  grails.compiler.*  !@GrailsCompileStatic  class  BookController  {     …  }

Maven-style Dependency Management• Use management block to declare managed dependencies

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!management  {      dependency  "commons-­‐logging:commons-­‐logging:1.1.3"  }

Hibernate Subqueries• Perform nested “in” or “notIn” sub queries that span domain

classes using where queries:

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def  employees  =  Employee.where  {          region.continent  in  ['APAC',  "EMEA"]  }.id()  !def  results  =  Sale.where  {        employee  in  employees  &&  total  >  50000  }.employee.list()

Hibernate Correlated Subqueries• Declare aliases using “def” for cross query references:

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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()

Hibernate Column Readers/Writers• Implement custom column readers and writers to transform

data when written or read from the database.

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class  Name  {          String  title          static  mapping  =  {                  title  write:'UPPER(?)',                            read:'REPEAT(title,  2)'          }  }

Hibernate 4 in Unit Tests (Coming Soon)• Test Hibernate 4 interaction in unit tests

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import  grails.test.mixin.hibernate.*  !@TestMixin(HibernateTestMixin)  class  PersonSpec  extends  Specification{          void  setupSpec()  {                  hibernateDomain([Person])          }        …  }

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/

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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:

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<configuration>        <grailsVersion>2.3.8</grailsVersion>  </configuration>  

Grails 2.4.x TODOs• Grails 2.4.4 - Out Soon • Spring Security Core 2.0 GA • Spring Web Flow Plugin Update • Bug Fixes

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2.4

!Q & AGrails 2.4

2.4

!The FutureGrails 3.0

3.0

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

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3.03.0

Grails 3.0: Goals

• Build on Spring Boot • Plugin System & Events • Support Multi Project Builds • Support Micro Services • Remove Bloat • Reduce Dependencies

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3.03.0

Spring IO Platform Reprise

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Jobs, Steps, Ingestion, Export, Controllers, REST, Channels, Adapters,

WEBINTEGRATION BATCH BIG DATA

SPRING CORE

FRAMEWOR SECURIT GROOV REACTO

DATA

RELATIONA NON-

BOOT

Bootable, Minimal, Ops-Ready

GRAILS XD IO

IO

Spring IO Platform

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Grails

Spring IO Platform

Spring XD

Spring Foundation

Apps

3rd Party Dependencies

Spring Boot

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/

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dependencies  {          compile  'commons-­‐lang:commons-­‐lang'  }

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

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Plugin Delineation

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Grails.sh

Static void m

ain

Gradle B

uild

Forked Grails Runtime

test-app

shellrun-app

console

Codegen Plugins

Build Time Plugins

Runtime Plugins

Gradle

• Allow Micro or Monolith Applications • Multi-Project Plugin Architectures • Run individual sub projects • Or run as a whole

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!Demo Grails 3.0 Gradle

3.0

Spring Boot

• Grails 3.0 to be built on Spring Boot • Boot to handle

• Embedded servers • Runnable JARs • WAR packaging • Scripting / Micro Services

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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

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Boot Powered Micro Services

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@Grab("com.h2database:h2:1.3.173")  import  grails.persistence.*  !@Entity  @Resource(uri='/books')  class  Book  {          String  title  }  

!Demo Grails 3.0 Micro Services

3.0

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

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Servlet 3.0 only and no web.xml• Thanks to Spring Boot, new servlets and filters can just be

Spring beans

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!def  doWithSpring  =  {          characterEncodingFilter(                    CharacterEncodingFilter)  {                          encoding  ='utf-­‐8'          }  }

Simplification• Removed

– UrlMappingsFilter – GrailsDispatcherServlet – SimpleGrailsController – Sitemesh Filter

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Old Grails 2.x Flow

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UrlMappingsFilterGrailsPageFilter

Decorate Request Forward Request

GrailsDispatherServlet

Delegate Request

GrailsController

Grails 3.0 Flow• GrailsDispatcherSerlvet 50 lines of code in 3.x,

but 545 lines in 2.x

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DispatcherServlet

Delegate Request

GrailsController

Benefits of Simplification• Less code to maintain • Better performance • Better integration with Spring • Fewer dependencies

• commons-fileupload gone • No internal forwarding

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Evolution of Metaprogramming

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Runtime Metaprogramming

(ExpandoMetaClass)

Compile time Metaprogramming(AST Transforms)

Traits & Transforms

Grails 1.x Grails 2.x Grails 3.x

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)

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trait  Controller  {      …      def  withFormat(Closure  callable)  {            …      }  }

Application Profiles

• Each profile will have distinct plugins, runtimes and packaging (JAR, WAR etc.)

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!$  grails  create-­‐app  myapp  -­‐-­‐profile=netty    $  cd  myapp  $  grails  package  $  java  -­‐jar  target/myapp.jar  !

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

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Profile Repository• All Profiles managed by git • Profiles checked out locally and periodically updated • Profiles wrap code generation infrastructure

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$  grails  create-­‐controller  foo  !Profile  .getCurrentProfile()  .getCommand('create-­‐controller')  .execute(  'foo'  )

Grails 3.0: Challenges

• Compatibility – Plugins – Build System

• Modularization – Servlet API independence – Refactoring

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3.0

!Q & AGrails 3.0

3.0

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