(Quick Reference)

1.1.3 Fonctionnalités du Web - Reference Documentation

Authors: Graeme Rocher, Peter Ledbrook, Marc Palmer, Jeff Brown, Luke Daley, Burt Beckwith

Version: null

1.1.3 Fonctionnalités du Web

Controller Actions as Methods

It is now possible to define controller actions as methods instead of using closures as in previous versions of Grails. In fact this is now the preferred way of expressing an action. For example:

// action as a method
def index() {

} // action as a closure def index = {

}

Binding Primitive Method Action Arguments

It is now possible to bind form parameters to action arguments where the name of the form element matches the argument name. For example given the following form:

<g:form name="myForm" action="save">
    <input name="name" />
    <input name="age" />
</g:form>

You can define an action that declares arguments for each input and automatically converts the parameters to the appropriate type:

def save(String name, int age) {
    // remaining
}

Static Resource Abstraction

A new static resource abstraction is included that allows declarative handling of JavaScript, CSS and image resources including automatic ordering, compression, caching and gzip handling.

Servlet 3.0 Async Features

Grails now supports Servlet 3.0 including the Asynchronous programming model defined by the specification:

def index() {
    def ctx = startAsync()
    ctx.start {
        new Book(title:"The Stand").save()
        render template:"books", model:[books:Book.list()]
        ctx.complete()
    }
}

Link Generation API

A general purpose LinkGenerator class is now available that is usable anywhere within a Grails application and not just within the context of a controller. For example if you need to generate links in a service or an asynchronous background job outside the scope of a request:

LinkGenerator grailsLinkGenerator

def generateLink() { grailsLinkGenerator.link(controller:"book", action:"list") }

Page Rendering API

Like the LinkGenerator the new PageRenderer can be used to render GSP pages outside the scope of a web request, such as in a scheduled job or web service. The PageRenderer class features a very similar API to the render method found within controllers:

grails.gsp.PageRenderer groovyPageRenderer

void welcomeUser(User user) { def contents = groovyPageRenderer.render(view:"/emails/welcomeLetter", model:[user: user]) sendEmail { to user.email body contents } }

The PageRenderer service also allows you to pre-process GSPs into HTML templates:

new File("/path/to/welcome.html").withWriter { w ->
    groovyPageRenderer.renderTo(view:"/page/content", w)
}

Filter Exclusions

Filters may now express controller, action and uri exclusions to offer more options for expressing to which requests a particular filter should be applied.

filter1(actionExclude: 'log*') {
    before = {
        // …
    }
}
filter2(controllerExclude: 'auth') {
    before = {
        // …
    }
}

filter3(uriExclude: '/secure*') { before = { // … } }

Performance Improvements

Performance of GSP page rendering has once again been improved by optimizing the GSP compiler to inline method calls where possible.

HTML5 Scaffolding

There is a new HTML5-based scaffolding UI:

jQuery by Default

The jQuery plugin is now the default JavaScript library installed into a Grails application. For backwards compatibility a Prototype plugin is available. Refer to the documentation on the Prototype plugin for installation instructions.