Important: #82445 - Migrate pages_language_overlay into pages¶
The functionality of "pages_language_overlay" has been migrated into "pages".
An upgrade wizard is in place to migrate all existing data into the "pages" database table.
All relations directly to "pages_language_overlay" are migrated to the newly created "pages" records as well.
Some rules for future development need to be clarified:
Default Language Page
previously exclusively available in "pages"
Holds the PID of the parent page
MUST be in place in order to create a translated page (not possible to create a translated page without having a default page in place)
Has always "l10n_parent" and "sys_language_uid" fields set to "0"
The "uid" of this record is automatically the PID for all records of this page
Translated Page (previously known as "pages_language_overlay")
Is identified as Translated Page by having a "sys_language_uid" field greater 0 and "l10n_parent" field containing the "uid" of the Default Language Page.
The value of the "pid" field is the same "pid" as of the Default Language Page - effectively putting the Translated Page and the Default Language Page on the same root-level.
The value of "sorting" is the same for all translated pages
The "uid" field is not used by anything currently within the TYPO3 Core.
The "hidden" field is set as "allowLanguageSynchronization"
The following details apply
Any TCA-based records (= subpages, content elements) still ALWAYS contain the pid to the Original Language Page, a DataHandler restriction ensures this constraint.
Backend: All UI elements like Element Browser, Page Browser etc. are restricted to only show the Default Language Pages to be selected (one can not link to a specific Translated Page).
Permissions are always fetched from the "Original Language Page"
DataHandler: Moving or deleting of a Default Language Page always moves/deletes the associated Translated Page records as well.
DataHandler: "sorting" and "pid" parameters of translations are always kept in sync one-to-one for translated pages. Translated pages cannot be moved themselves.
Permissions: Restricting a Backend User/Group to a language limits the access to "pages" to a specific language in page module.
Permissions: All existing "pages_language_overlay" permissions are merged into "pages" options for all records - when a Backend User/Group is limited to only certain languages (and not the default language) this , the . If a Backend User/Group does have permission on "pages_language_overlay" but not "pages", the Backend User/Group has automatically assigned all translations (sys_language_uid) as language limitations.
Frontend: Requesting a page can be done with ?id=originalpage&L=1 or ?id=translatedpage where "?id=translatedpage" internally resolves the "id" parameter to the uid of the Original Language Page and the "L" parameter resolved to the "sys_language_uid" corresponding in the TypoScript options.
Frontend: All "pid" checks are always done against the Original Language Page, as all records still sit on that page.
Frontend: Generating a link to a Default Language Page with a current Translated Page generated, will exchange the target on link creation to the targeted Translated Page automatically.