The LinkHandler API

The LinkHandler API currently consists of 7 LinkHandler classes and the TYPO3\CMS\Recordlist\LinkHandler\LinkHandlerInterface. The LinkHandlerInterface can be implemented to create custom LinkHandlers.

Most LinkHandlers cannot receive additional configuration, they are marked as @internal and contain neither hooks nor events. They are therefore of interest to Core developers only.

Current LinkHandlers:

  • The PageLinkHandler: for linking pages and content

  • The RecordLinkHandler: for linking any kind of record

  • UrlLinkHandler: for linking external urls

  • FileLinkHandler: for linking files in the File abstraction layer (FAL)

  • FolderLinkHandler: for linking to directories

  • MailLinkHandler: for linking mail

  • TelephoneLinkHandler: for linking phone numbers

Note

In the system extension core there are also classes ending on "LinkHandler". However those implement the interface LinkHandlingInterface and are part of the LinkHandling API, not the LinkHandler API.

The following LinkHandlers are of interest:

The links are now stored in the database with the syntax <a href="t3://record?identifier=anIdentifier&amp;uid=456">A link</a>.

  1. TypoScript is used to generate the actual link in the frontend.

    config.recordLinks.anIdentifier {
        // Do not force link generation when the record is hidden
        forceLink = 0
        typolink {
            parameter = 123
            additionalParams.data = field:uid
            additionalParams.wrap = &tx_example_pi1[item]=|&tx_example_pi1[controller]=Item&tx_example_pi1[action]=show
        }
    }
    

    Important

    Do not change the identifier after links have been created using the LinkHandler. The identifier will be stored as part of the link in the database.

LinkHandler page TSconfig options

The minimal page TSconfig configuration is:

EXT:some_extension/Configuration/page.tsconfig
TCEMAIN.linkHandler.anIdentifier {
    handler = TYPO3\CMS\Recordlist\LinkHandler\RecordLinkHandler
    label = LLL:EXT:extension/Resources/Private/Language/locallang.xlf:link.customTab
    configuration {
        table = tx_example_domain_model_item
    }
}

See Link handler configuration for all available options.

Example: news records from one storage pid

The following configuration hides the page tree and shows news records only from the defined storage page:

EXT:some_extension/Configuration/page.tsconfig
TCEMAIN.linkHandler.news {
    handler = TYPO3\CMS\Recordlist\LinkHandler\RecordLinkHandler
    label = News
    configuration {
        table = tx_news_domain_model_news
        storagePid = 123
        hidePageTree = 1
    }
    displayAfter = mail
}

It is possible to have another configuration using another storagePid which also contains news records.

This configuration shows a reduced page tree starting at page with uid 42:

EXT:some_extension/Configuration/page.tsconfig
TCEMAIN.linkHandler.bookreports {
    handler = TYPO3\CMS\Recordlist\LinkHandler\RecordLinkHandler
    label = Book Reports
    configuration {
        table = tx_news_domain_model_news
        storagePid = 42
        pageTreeMountPoints = 42
        hidePageTree = 0
    }
}

The PageTSconfig of the LinkHandler is being used in sysext recordlist in class \TYPO3\CMS\Recordlist\LinkHandler\RecordLinkHandler which does not contain Hooks or Slots.

LinkHandler TypoScript options

A configuration could look like this:

EXT:some_extension/Configuration/TypoScript/setup.typoscript
config.recordLinks.anIdentifier {
    forceLink = 0

    typolink {
        parameter = 123
        additionalParams.data = field:uid
        additionalParams.wrap = &tx_example_pi1[item]=|
    }
}

The TypoScript Configuration of the LinkHandler is being used in sysext frontend in class TYPO3\CMS\Frontend\Typolink\DatabaseRecordLinkBuilder.

Example: news records displayed on fixed detail page

The following displays the link to the news on a detail page:

EXT:some_extension/Configuration/TypoScript/setup.typoscript
config.recordLinks.news {
   typolink {
      parameter = 123
      additionalParams.data = field:uid
      additionalParams.wrap = &tx_news_pi1[controller]=News&tx_news_pi1[action]=detail&tx_news_pi1[news]=|
   }
}

Once more if the book reports that are also saved as tx_news_domain_model_news record should be displayed on their own detail page you can do it like this:

EXT:some_extension/Configuration/TypoScript/setup.typoscript
config.recordLinks.bookreports  {
   typolink {
      parameter = 987
      additionalParams.data = field:uid
      additionalParams.wrap = &tx_news_pi1[controller]=News&tx_news_pi1[action]=detail&tx_news_pi1[news]=|
   }
}