optaros surf code camp dispatcher

Alfresco Surf Code Camp

Dispatcher and Site Construction

12/12/08 Optaros and Client confidential. All rights reserved. 2

Objectives

By the end of this module you should know• How pages are dispatched• How pages are assembled by invoking component renderers• How Page Types & Themes work together

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You've used web script-based components as Share

Dashlets

Now let's learn about how Surf sites and Surf pages

are built

Site Dispatcher

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The site dispatcher is responsible for figuring out

which page should be assembled for a given request,

and then assembling the page by invoking renderersPage

Renderer

Renderer Renderer

Renderer

Site Dispatcher

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Model Objects contain information about site

construction

A web site looks to these objects during render

They define pages and page layout

They define where components appear on pages

Model Objects

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Model Objects are XML files

Here is an example of a component XML file

<?xml version='1.0' encoding='UTF-8'?><component> <scope>global</scope> <region-id>footer</region-id> <source-id>global</source-id> <url>/age/footer</url> <properties> <custom1>My custom property value</custom1> </properties></component>

Model Objects

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Types

Component Type

Template Type

Page Type

List of Model Objects

Instances

• Component

• Template Instance

• Page

Associations

• Page Association

• Content Association

Site

• Configuration

• Theme

• Chrome


Key Surf Page Construction Concepts

SomeTemplate.ftl

Header

Gutter Body

Footer

Home

Blog About

Pages

Template Instances &Renderers

Regions

Component (Web Script)

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Component Type

TemplateType

PageType

Component

TemplateInstance

Page PageAssociation

ContentAssociation

Configuration Theme

Chrome

Model Objects Graph

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Regardless of the path, it always comes down to a Page

• An Object is requested -> What page should display it?• A Page Type is requested -> Which page is appropriate for this

Theme?• A specific Page is requested

URIServlet

DispatcherServlet

Page Type

Page

Object

Resolves to a page

Resolves to a page

To Rendering

Requests

Dispatching

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1.Example: Hitting the home page http://labs3c:8580/alfwf/page?p=home

2.Look up Page (in /site-data/pages) ‏

Page has a template instance.

3.Look up Template Instance (in /site-data/template-

instances) ‏

4.Look up Renderer for Template In this case the Renderer is a FreeMarker Template Process regions on page by id

5.Find Component Bindings for those region ids

6.Look up Components (in /site-data/components) ‏

Page Dispatching Logic

http://labs3c:8580/alfwf/page?p=home

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Look up the page object by page id: home• /WEB-INF/classes/alfresco/site-data/pages

Look up the template by template id: home• /WEB-INF/classes/alfresco/site-data/template-instances

<?xml version='1.0' encoding='UTF-8'?><page> <title>Home Page</title> <template-instance>home</template-instance> <authentication>none</authentication></page>

<?xml version='1.0' encoding='UTF-8'?><template-instance> <template-type>freemarker</template-type> <url>/sample/home</url></template-instance>


Potentially confusing

shortcut here!

<?xml version='1.0' encoding='UTF-8'?><template-instance> <template-type>/sample/home</template-type></template-instance>

OR

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Execute the Template Renderer for path: /sample/home

• FreeMarker renderer• /WEB-INF/classes/alfresco/templates/sample/home.ftl

Execute the region tag and find matching components• /WEB-INF/classes/alfresco/site-data/components• Search for components in page scope, bound to home page for

the region ‘SomeImage’• page.test.home.xml

<html> <body> <@region id=“SomeImage” scope=“page” /> </body></html>


Components have a naming convention which is duplicative of the XML it contains. Currently, the XML page, scope, and region XML are ignored, but in the future, the naming convention will be dropped.

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Analyze the Component and prepare to render it• /WEB-INF/classes/alfresco/site-data/components

The url maps to a web script• URL = /blocks/image

The properties of the component are fed into the Web Script

<?xml version='1.0' encoding='UTF-8'?><component> <scope>page</scope> <region-id>SomeImage</region-id> <source-id>home</source-id> <url>/blocks/image</url> <properties> <src>${url.context}/images/masay.jpg</src> </properties></component>


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blocks/image is an Image Display component

The Presentation Web Script fetches data from component instance

The FreeMarker based view then renders the output

var src = instance.properties[“src”];if(src != null)‏{

// proceed}

<img src=“${src}” />


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The template would execute

SomeImage


home.ftl


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Generated output



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Page Types are used to define a general “class” or type of pages

Examples:• Login• Profile• Others?

Example: Hitting the login page• http://labs3c:8580/alfwf/page?pt=login

Page Type Dispatching Logic

http://labs3c:8580/alfwf/page?pt=login

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First, see if there is a configured theme● Themes can specify overrides for page types● Default themes are specified by site configuration objects

<?xml version='1.0' encoding='UTF-8'?><theme> <title>Extranet - Enterprise Theme</title> <page-types> <page-type> <id>login</id> <page-instance-id>sample-login</page-instance-id> </page-type> </page-types></theme>


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If nothing specifed in a theme, see if the framework has a default

• The web-framework-config*.xml files can specify defaults

<alfresco-config> <config evaluator="string-compare" condition="WebFramework"> <web-framework> <application-defaults> <theme>newtheme</theme> <page-type> <id>login</id> <page-instance-id>sample-login</page-instance-id> </page-type> </application-defaults> </web-framework> </config></alfresco-config>


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Last resort, try to use a generic page• Looks for a page with id = generic


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At this point, we have a page object

Dispatch to page as before


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Example: Displaying a content object

http://labs3c:8580/alfwf/page?o=workspace://SpacesStore/56923743-7436-482e-b1cf-eda326d11dc2

• Assumes the default endpoint

• “Load content object with this id from the default endpoint”

http://labs3c:8580/alfwf/page?

o=workspace://SpacesStore/56923743-7436-482e-b1cf-

eda326d11dc2&endpointId=alfresco

• Uses a specific endpoint

• “Load content object with this id from the alfresco endpoint”

Object Dispatching Logic

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Look up the ContentLoader implementation• A content loader that knows how to load content from this

endpoint<alfresco-config> <config evaluator="string-compare" condition="WebFramework"> <web-framework> <content-loader> <id>alfresco</id> <name>Alfresco Content Loader</name> <class>org.alfresco.web.site.AlfrescoContentLoader</class> <endpoint>alfresco</endpoint> </content-loader> </web-framework> </config></alfresco-config>


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If a ContentLoader is found, then load the object

Then, look for Content Association instances which describe a match for this content object

• /WEB-INF/classes/alfresco/site-data/content-associations

Describes a page that can be used to display content of type: {http://www.alfresco.org/model/content/1.0}content

<?xml version="1.0" encoding="UTF-8"?>

<content-association> <source-id>{http://www.alfresco.org/model/content/1.0}content</source-id> <dest-id>content-details</dest-id> <assoc-type>page</assoc-type></content-association>


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At this point, we have a page object

Dispatch to page as before


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/WEB-INF/classes/alfresco

/site-data

/chrome

/components

/component-types

/configurations

/content-associations

/page-associations

/pages

/page-types

/template-instances

/template-types

/themes

Site Data

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/site-webscripts

/example

/component.get.desc.xml

/component.get.js

/component.get.html.ftl

/component.get.head.ftl

/component.get.properties

/component.get.config

Components

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/templates

/example

/template.js

/template.ftl

/template.head.ftl

Templates


Wrap-up

In this module, you learned...• How Surf model objects inter-relate• Three ways pages are dispatched

– Specific page– Page type– Object

• Pages are assembled by invoking component renderers

optaros surf code camp dispatcher

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