The SXA pipelines

Abstract

Understand how the SXA pipelines and their processors work.

Understanding how the SXA pipelines and their processors work provides you with an insight into how dependencies are rendered, how tokens for rendering variants are created, how CSS classes are generated, and so on.

A pipeline consists of a sequence of processors. A processor is a .NET class that implements a method. When a pipeline is invoked, the processors are run in order. You can extend and customize the pipelines by adding or replacing processors. Extending a pipeline involves modifying the pipeline definition located in a Sitecore patch file.

This topic describes the following pipelines:

resolveVariantTokens

The resolveVariantTokens pipeline is used to create tokens for rendering variants.

This pipeline includes the following processors:

Processor	Description
ResolveIFileTypeIcon	Renders the span HTML element with the class according to the extension of the file.
ResolveItemId	Specifies the ID of the content item to be resolved.
ResolveItemName	Specifies the name of the content item to be resolved.
ResolveSize	Renders the file size.

ioc

The Inversion of Control (IoC) design principle allows you to change rendering dependencies without changing the rendering itself. The ioc pipeline is defined in the Sitecore.XA.Foundation.IoC.config file and is used for adding processors in which you can register your custom services in the container.

For example, you can add the RegisterPageContentServices processor to register services used in the Page Content feature.

    <pipelines>
      <ioc>
        <processor type="Sitecore.XA.Feature.PageContent.Pipelines.IoC.RegisterPageContentServices, Sitecore.XA.Feature.PageContent" />
      </ioc>
    </pipelines>

decoratePage

The decoratePage pipeline is used to decorate the page <body> tag with attributes. These can be standard attributes, such as id or class, but you can also add custom data attributes.

decorateRendering

The decorateRendering pipeline is used to decorate the rendering's outer <div> tag with attributes. These can be standard attributes, such as id or class, but you can also add custom data attributes.

<div class="component title">
<div class="component-content">
<h2 class="field-title">
Title of the page
</h2>
</div>
</div>

mediaRequestHandler

The mediaRequestHandler pipeline is used in the SXA media requests handler. The mediaRequestHandler pipeline is defined in the Sitecore.XA.Foundation.MediaRequestHandler.config file.

This file extends the standard media request handler by adding a pipeline that implements custom functionalities such as the support of wireframe images or providing optimized assets.

This pipeline includes the following processors:

Processor	Description
ParseMediaRequest	Checks if the HTTP request is a valid media type. If not, the pipeline is aborted.
GetMediaFromUrl	Determines the media item from the URL that is stored in HTTP request.
HandleErrors	Redirects the user to an error page.

resolveTokens

The resolveTokens pipeline is used to resolve tokens that can be used in queries. For example, $site, $tenant, $currenttemplate, $home, and $pageDesigns. By adding new processors to this pipeline, you can design new tokens.

This pipeline is defined in the Sitecore.XA.Foundation.TokenResolution.config file and includes the following processors:

Processor	Description
CurrentTemplateToken	Determines the current tokens used.
EscapeQueryTokens	Used to escape tokens that are used in Sitecore queries.

assetService

The assetService pipeline is responsible for assets optimization. This pipeline includes the AddEditingtheme processor, which you can use to add a theme when you are in Edit mode.

<assetService>
        <processor type="Sitecore.XA.Foundation.Editing.Pipelines.AssetService.AddEditingTheme, Sitecore.XA.Foundation.Editing" />
      </assetService>

getRobotsContent

The getRobotsContent pipeline is used to extend the response provided to search crawler robots in the robots.txt file. The Robots.txt file is a simple text file on your site’s root directory that tells search engine robots what to crawl and what not to crawl on your site. The getRobotsContent pipeline contains the following processors:

Processor	Description
GetContentFromSettings	Checks if the robots' content field is filled and uses its value.
GetDefaultRobotsContent	Checks the `robots.txt` file for a value when the robots' content field is empty.
AppendSitemapUrl	Adds the path of the `sitemap.xml` file to the robots' content field.

getRenderingCssClasses

The getRenderingCssClasses pipeline is used to gather CSS classes that will be applied on rendering (added to the list of CSS classes on rendering).

refreshHttpRoutes

The refreshHttpRoutes pipeline is used to refresh HTTP routes after changes in site configuration.

getVelocityTemplateRenderers

The getVelocityTemplateRenderers pipeline is used to add a custom renderer that later on can be used in the NVelocity template. This pipeline is defined in the Sitecore.XA.Foundation.RenderingVariants.config file. It contains the following processors:

Processor	Description
InitializeVelocityContext	Initializes the pipeline argument objects.
AddTemplateRenderers	Provides two custom tools that format data and time values (dateTool) and numbers (numberTool) in a NVelocity template.