Grails

2008年7月18日 (五) 13:58的版本

Grails关注将"规约编程"(coding by convention)引入Groovy。它是一个开放源网络应用构架， 对Groovy语言起到杠杆作用，并且对Java网络开发起到补足作用。你可以用Grails 作为独立开发环境, 它隐藏了所有的配置细节，也可以将它同和入你的Java商务逻辑。

Grails关注与使开发最简化，而且Grails的解决方案来自于广泛的开发者，不只局限于Java社区。

Grails构建在开源技术如Spring、Hibernate和SiteMesh之上，提供了一个类似于Rails 的平台可以与Java平台无缝集成. Groovy是一种“动态”或指令语言。动态语言一般用来加速和简化程序撰写。与Python或Ruby等其他指令语言不同的是，用Groovy撰写的程序，可与Java虚拟器结合。

Install

wget http://download.huihoo.com/grails/grails-bin-1.0.1.zip
GRAILS_HOME= C:\grails-1.0.1 or /usr/local/grails-1.0.1 
Add the "%GRAILS_HOME%\bin" directory to your PATH environment variable
Add the "%GRAILS_HOME%\ant\bin directory to your PATH environment variable.

grails create-app my-project
cd my-project
grails create-domain-class Book

my-project\grails-app\domain\Book.groovy

class Book {
   String title
   String author
}

my-project\grails-app\conf\BootStrap.groovy

class BootStrap {

   def init = { servletContext ->
       // Create some test data
       new Book(author:"Stephen King",title:"The Shining").save()
       new Book(author:"James Patterson",title:"Along Came a Spider").save()
   }
   def destroy = {
   }
}

my-project\grails-app\controllers\BookController.groovy

class BookController {
    def scaffold = Book
}
grails run-app // or grails dev run-app or grails prod run-app
http://localhost:8080/my-project/
http://localhost:8080/my-project/book
运行成功 :)

To upgrade your existing Grails projects you must run:

grails clean
grails upgrade

NetBeans

http://wiki.netbeans.org/groovy

PostgreSQL

Grails and PostgreSQL

下载例子: http://docs.huihoo.com/postgresql/regperf.zip

More Detail: http://blogs.sun.com/tomdaly/entry/regperf_v1_running_the_grails

CRUD

Create

def p = new Person(name:"Jack", age:32, lastVisit:new Date())
p.save()

Read

def p = Person.get(1)
assert 1 == p.id

Update

def p = Person.get(1)
p.name = "Peter"
p.save()

Delete

def p = Person.get(1)
p.delete()

GORM

One-to-one

class Face {
    Nose nose
}
class Nose {	 
	static belongsTo = [face:Face]
}
new Face(nose:new Nose()).save() // ok 

def f = Face.get(1)
f.delete() // both Face and Nose deleted

One-to-many

class Author {
   static hasMany = [ books : Book ]
   String name 
} 
class Book { 
   static belongsTo = [author:Author] 
   String title 
}

Many-to-many

class Book {
  static belongsTo = Author
  static hasMany = [authors:Author]
  String title
}
class Author {
  static hasMany = [books:Book]
  String name
}

Grails 1.0.3 Scaffolding feature does not currently support many-to-many relationship and hence you must write the code to manage the relationship yourself

Grails ManyToMany GORM Example

GPath: Groovy's ability to manipulate collections via GPath and methods like sort, findAll and so on combined with GORM results in a powerful combination.

def books = Book.list()
def books = Book.list(offset:10, max:20)
def books = Book.list(sort:"title", order:"asc")
def book = Book.get(23)
def books = Book.getAll(23, 93, 81)
def book = Book.findByTitle("The Stand")

Usage

grails help

• grails bootstrap
• grails bug-report
• grails clean
• grails compile
• grails console
• grails create-app
• grails create-controller
• grails create-domain-class
• grails create-integration-test
• grails create-plugin
• grails create-script
• grails create-service
• grails create-tag-lib
• grails create-unit-test
• grails doc
• grails generate-all
• grails generate-controller
• grails generate-views
• grails help
• grails init
• grails install-plugin
• grails install-templates
• grails list-plugins
• grails package
• grails package-plugin
• grails package-plugins
• grails plugin-info
• grails release-plugin
• grails run-app
• grails run-app-https
• grails set-proxy
• grails set-version
• grails shell
• grails stats
• grails test-app
• grails upgrade
• grails war

Service

Services in Grails are seen as the place to put the majority of the logic in your application, leaving controllers responsible for handling request flow via redirects and so on.

grails create-service simple

Plugins

grails list-plugins

To find more info about plugin type 'grails plugin-info [NAME]'

To install type 'grails install-plugin [NAME] [VERSION]'

grails install-plugin yui 2.5.0

For further info visit http://grails.org/Plugins

GSP

<html>
   <body>
    <%-- This is my comment --%>  //  <%="Hello GSP!" %>  JSP-style comment
    <%="Hello GSP!" %> 
   </body>
</html>
<%@ page import="java.awt.*" %>
<%@ page contentType="text/json" %>

GSP Tags

<g:example attr="${new Date()}" attr2="[one:'one', two:'two']">
   Hello world
</g:example>

Ext

Grails Ext Userinterface

grails install-plugin ext or grails install-plugin ext 2.0.2
Ext has installed under your project's /web-app/js/ext/2.0.2

More Detail: http://grails.org/Ext+Plugin

Using ExtJS Layouts with Grails Layouts

GWT

grails install-plugin gwt
grails create-gwt-module <module> 
grails compile-gwt-modules
grails create-gwt-page
grails events
grails run-gwt-client

More Detail: http://www.grails.org/GWT+Plugin

GWTGrailsTutorial: http://code.google.com/p/derjanandhisblog/wiki/GWTGrailsTutorial

JSON

def list = {
	def results = Book.list()
	render(contentType:"text/json") {
		books {
			for(b in results) {
				book(title:b.title)
			}
		}	
	}
}

Result

[
	{title:"ActiveRecord Tutorial"}, 
	{title:"Grails Tutorial"}
]

Web Flow

Spring Web Flow

Grails supports the creation of web flows built on the Spring Web Flow project.

class BookController {
   …
   def shoppingCartFlow = {
       showCart {
           on("checkout").to "enterPersonalDetails"           
           on("continueShopping").to "displayCatalogue"
       }
       …
       displayCatalogue {
            redirect(controller:"catalogue", action:"show")
       }
       displayInvoice()
   }
}

Web flows don't require an HTTP session, but instead store their state in a serialized form, which is then restored using a flow execution key that Grails passes around as a request parameter. This makes flows far more scalable than other forms of stateful application that use the HttpSession and its inherit memory and clustering concerns.

GrailsFlow is a Workflow and Business Process Engine written in Groovy and Grails.

Rules

• GroovyRules

Tutorials

Build Your First Grails Project: A Grails-Powered Blog

NetBeans

Groovy and Grails 在开发版中已经可用 http://wiki.netbeans.org/groovy

开发版: http://deadlock.netbeans.org/hudson/job/trunk/lastSuccessfulBuild/artifact/nbbuild/dist/zip/

REST

As an example the following mappings provide a RESTful API URL mappings for the BookController:

static mappings = {
   "/product/$id"(controller:"product"){
       action = [GET:"show", PUT:"update", DELETE:"delete", POST:"save"]
   }	
}

SOAP

Grails supports SOAP through the XFire plug-in which uses the popular XFire SOAP stack to integrate SOAP support into Grails.

class BookService {
 static expose=['xfire']
 Book[] getBooks()
  { Book.list() as Book[] 
} }
http://127.0.0.1:8080/your_grails_app/services/book?wsdl

Ajax

Ajax with GWT

Ajax with Prototype

Ajax with Dojo

Validation

class User {
    String login
    String password
    String email
    Integer age

   static constraints = {
       login(size:5..15, blank:false, unique:true)
       password(size:5..15, blank:false)
       email(email:true, blank:false)
       age(min:18, nullable:false)
   }
}

Testing

grails test-app SimpleController BookController

Unit Testing

Integration Testing

Functional Testing

Grials support for Canoo WebTest via a plug-in.

Canoo WebTest

grails install-plugin webtest

Internationalization

grails-app/i18n

messages.properties
messages_zh.properties
messages_de.properties
messages_es.properties

etc.

Security

class SecurityFilters {
  def filters = {
      loginCheck(controller:'*', action:'*') {
          before = {
             if(!session.user && actionName != "login") {
                 redirect(controller:"user",action:"login")
                 return false					
}} } } }

Acegi

Grails AcegiSecurity Create User on BootStrap

JSecurity

class ExampleController extends JsecAuthBase {
    static accessControl = {
        // All actions require the 'Observer' role.
        role(name: 'Observer')
        // The 'edit' action requires the 'Administrator' 
        role. role(name: 'Administrator', action: 'edit')
        // Alternatively, several actions can be specified. 
        role(name: 'Administrator', only: [ 'create', 'edit', 'save', 'update' ]) }
… }

RSS and Atom

Feeds plug-in available for Grails that provides a RSS and Atom builder using the popular ROME library.

def feed = {
    render(feedType:"rss", feedVersion:"2.0") {
        title = "My test feed"
        link = "http://your.test.server/yourController/feed"

        Article.list().each() { 
            entry(it.title) { 
                link = "http://your.test.server/article/${it.id}" 
                it.content // return the content 
} } } }

Grails and Spring

Grails and Hibernate

Scaffolding

class BookController {
   def scaffold = Book
   def changeAuthor = { 
       def b = Book.get( params["id"] ) 
       b.author = Author.get( params["author.id"] ) 
       b.save()
       redirect(action:show) 
} }

Deployment

grails war /glassfish-v2ur2/domains/domain1/applications/j2ee-modules/blog.war

Mobile

Grails on iPhone

• Grails and the mobile Web
• Grails 与移动 Web

相关项目

• OpenSymbolic
• Scala

Samples

http://svn.codehaus.org/grails/trunk/grails-samples/

成功应用

• http://grails.org/
• http://www.grassr.com/

http://www.grails.org/Success+Stories

相关链接

• http://grails.codehaus.org/
• http://www.g2one.com/
• http://www.groovygrails.com
• http://download.huihoo.com/grails/
• http://docs.huihoo.com/grails/
• 精通 Grails 系列: http://www.ibm.com/developerworks/cn/java/j-grails/