Sling Cheatsheet

This tutorial is to learn how Apache Sling Resource Resolution is done in AEM.

URL Decomposition :

URL – http://localhost:4502/cf#/content/aemTutorials/sightlyPage.test.html/a/b?x=12

Protocol: http
Host: localhost:4502
Content path : content/aemTutorials/sightlyPage
Selector(s) : .test
Extension : html
Suffix : a/b
Param : x=12

Sling Resource Resolution – Mapping URL to Respective JCR Node :

Step-1: Double click on a page in siteadmin , to open respective page in browser.

Step-2-3-4-5:  Analyse the URL /contents/aemTutorials/sightlyPage it is known as content path.

• The /content path refers to the path of content folder in crx de.
• /aemTutorials refers to the package under contents folder.
• /sightlyPage refers to our page that we have created under siteadmin. jcr:content of sightlyPage contains a property sling:ResourceType. Which tells sling where our component is located. As shown in above figure it is at training/components/myComponent , means sling needs to check for myComponent under /apps folder.

Step-6: Analyse selector and extension  test.html.

• Sling appends the selector and extension after the component name i.e myComponent.test.html If it found this component then it render it else it drops the extension and search again.

Note:- Sling decides rendering of script on the basis of selector + extension . First priority goes to selector, if no selector is available then priority goes to extension.

Now if we double click our page http://localhost:4502/cf#/content/sample/testing.html  then by default myComponent.jsp script will be called because here .html is an extension not selector .

Between jsp and html first priority goes to jsp as by default a component is linked to jsp at the time of creation.

So the final priority order will be myComponent.html.jsp–>html.jsp–>myComponent.jsp –>myComponent.html