Tassos Marinos Developer of Joomla Extensions

How to use the Custom Code Content Type

Updated 31 Mar, 2022

There are cases where you want to markup a page with a Content Type not supported yet by the Google Structured Data extension or just place your own custom structured data code. With the proper knowledge of the Schema.org vocabulary and a list of Smart Tags, you can create your own JSON-LD Structured Data code for literally any schema.org type. Let's see how you can make that happen.

The Available Smart Tags


  • gsd.item.id
  • gsd.item.alias
  • gsd.item.headline
  • gsd.item.description
  • gsd.item.introtext
  • gsd.item.fulltext
  • gsd.item.image
  • gsd.item.imagetext
  • gsd.item.created
  • gsd.item.publish_up
  • gsd.item.publish_down
  • gsd.item.modified
  • gsd.item.ratingvalue
  • gsd.item.reviewcount
  • gsd.item.metakey
  • gsd.item.metadesc
  • url
  • user.id
  • user.name
  • user.firstname
  • user.lastname
  • user.login
  • user.email

Joomla Content

  • gsd.item.image_intro
  • gsd.item.image_full


  • gsd.item.startdate
  • gsd.item.enddate
  • gsd.item.offerprice
  • gsd.item.locationname
  • gsd.item.locationaddress
  • gsd.item.offercurrency
  • gsd.item.offerinvtentorylevel
  • gsd.item.offerstartdate


  • gsd.item.sku
  • gsd.item.brand
  • gsd.item.offerPrice
  • gsd.item.currency
  • gsd.item.offerAvailability

Page Info

  • page.title
  • page.desc
  • page.keywords
  • page.lang
  • page.generator

Site Info

  • gsd.sitename
  • gsd.siteurl
  • gsd.sitelogo
  • site.email

Smart Tags Syntax

To use the Smart Tags, you will need to use the following syntax:

The above Smart Tags are the same across all integrations but some are differentiated due to type of the integration.

Custom Fields Smart Tags

Other than the Smart Tags mentioned above, which are available for all Google Structured Data Items, some Integrations provide extra Custom Fields that can be used via the Mapping Option.

gsd custom fields smart tags mapping option

To use a Custom Field as a Smart Tag, first, you will need to find the key/name of the Custom Field. Since we are using the Joomla Content Integration in the example above, we can head to Content > Fields and select the URL field to find its key/name.

Every Integration that supports Custom Fields will have a similar page where you can pick the key/name of each Custom Field in order to use it's Smart Tag.

gsd custom fields smart tags mapping option 2

The Syntax to use any Custom Field is the following: {gsd.item.cf.CUSTOM_FIELD_NAME}

To use the above Custom Field, the syntax can be changed to: {gsd.item.cf.url}

How can I add a Custom Code?

Google Structured Data provides you with plenty content types. You may be in need to use a Content Type that is not currently supported. You can view all of Google's Content Types in the following link, Google Structured Data.

After you grab the markup provided by Google, customize it to fit your needs and then head over to Google Structured Data > Items > New > Select Custom Code as Content Type and then add your markup on the textarea named Custom Code that will appear as you can see in the screenshot below:

gsd custom code

This feature is intended to be used by advanced users. Use it only if you know what you're doing as it can break your site.