Templates

Last update: May 3, 2023

CREATED FOR:

  • Developer
CAUTION
AEM 6.4 has reached the end of extended support and this documentation is no longer updated. For further details, see our technical support periods. Find the supported versions here.

Templates are used at various points in AEM:

The following templates are covered in detail:

Templates - Pages

AEM now offers two basic types of templates for creating pages:

NOTE
When using a template to create a new page there is no visible difference (to the page author) and no indication of the type of template being used.

Editable Templates

Editable templates are now cosidered best practices for developing with AEM.

The advantages of Editable Templates:

  • Can be created and edited by your authors.

  • Have been introduced to allow you to define the following for any pages created with the template:

    • the structure
    • the initial content
    • content policies

  • After the new page is created a dynamic connection is maintained between the page and the template; this means that changes to the template structure will be reflected on any pages created with that template (changes to the initial content will not be reflected).

  • Uses content policies (edited from the template editor) to persist the design properties (does not use Design mode within the page editor).

  • Are stored under /conf

  • See Editable Templates for further information.

NOTE
An AEM Community Article is available explaining how to develop an Experience Manager site with Editable Templates, see Creating an Adobe Experience Manager 6.4 website using Editable Templates.

Static Templates

Static Templates:

  • Must be defined and configured by your developers.
  • This was the original templating system of AEM and has been available for many versions.
  • A static template is a hierarchy of nodes that has the same structure as the page to be created, but without any actual content.
  • Are copied to create the new page, no dynamic connection exists after this.
  • Uses Design Mode to persist design properties.
  • Are stored under /apps
  • See Static Templates for further information.
NOTE
As of AEM 6.4 the use of Static Templates is not considered a best practice. Use Editable Templates instead.
AEM Modernization tools can help you migrate from static to editable templates.

Template Availability

CAUTION
AEM offers multiple properties to control the templates allowed under Sites. However, combining them can lead to very complex rules that are difficult to track and manage.
Therefore, Adobe recommends that you start simple, by defining:

  • only the cq:allowedTemplates property

  • only on the site root

For an example, see We.Retail: /content/we-retail/jcr:content
The properties allowedPaths, allowedParents, and allowedChildren can also be placed on the templates to define more sophisticated rules. However, when possible, it is much simpler to define further cq:allowedTemplates properties on sub-sections of the site if there is a need to further restrict the allowed templates.
An additional advantage is that the cq:allowedTemplates properties can be updated by an author in the Advanced tab of the Page Properties. The other template properties cannot be updated using the (standard) UI, so would need a developer to maintain the rules and a code deployment for every change.

When creating a new page in the site admin interface, the list of available templates depends on the location of the new page and the restrictions on placement specified in each template.

The following properties determine whether a template T is allowed to be used for a new page to be placed as a child of page P. Each of these properties is a multi-value string holding zero or more Regular Expressions that are used for matching with paths:

  • The cq:allowedTemplates property of the jcr:content subnode of P or an ancestor of P.

  • The allowedPaths property of T.

  • The allowedParents property of T.

  • The allowedChildren property of the template of P.

The evaluation works as follows:

  • The first non-empty cq:allowedTemplates property found while ascending the page hierarchy starting with P is matched against the path of T. If none of the values match, T is rejected.

  • If T has a non-empty allowedPaths property, but none of the values match the path of P, T is rejected.

  • If both of the above properties are either empty or non-existent, T is rejected unless it belongs to the same application as P. T belongs to the same application as P if and only if the name of the second level of the path of T is the same as the name of the second level of the path of P. For example, the template /apps/geometrixx/templates/foo belongs to the same application as the page /content/geometrixx.

  • If T has an non-empty allowedParents property, but none of the values match the path of P, T is rejected.

  • If the template of P has a non-empty allowedChildren property, but none of the values match the path of T, T is rejected.

  • In all other cases, T is allowed.

The following diagram depicts the template evaluation process:

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