Juliepr MSLS Helper

Extends Multisite-Language-Switcher (https://github.com/lloc/Multisite-Language-Switcher/) with shared media, source date/slug/author copying, imported link rewriting, 302 redirects to original content and daily orphaned option cleanup.

Requirements

• WordPress Multisite 6.5 or later and PHP 7.4 or later.
• Multisite Language Switcher with Content Import enabled.
• A shared media library plugin (for example https://github.com/humanmade/network-media-library/) that resolves the same attachment ID on both the source and destination sites.

Installation

1. Copy the juliepr-msls-helper directory into wp-content/plugins/ as a standalone plugin, alongside MSLS.
2. Network activate Juliepr MSLS Helper, MSLS, and your shared media library plugin.
3. When importing content through MSLS, select Featured Image → Linking.

Network settings

Open Network Admin → Settings → MSLS Helper. Settings apply to all sites in the current network and can only be changed by a user with permission to manage network options.

• Enable global media library integration — enabled by default. Turning it off restores the standard MSLS featured image importer.
• Copy the source date, slug and author — enabled by default. Turning it off disables helper field copying in both Quick Create and Content Import, along with the helper's publication date display adjustment.
• Rewrite imported links to the translation site — enabled by default. Controls text link rewriting in both Quick Create and Content Import.
• Redirect missing translations to the source site — enabled by default. Sends an HTTP 302 redirect for missing content when the original exists.
• Source site ID for 404 redirects — defaults to 1. Choose an active site in the current network; this setting only controls the 404 fallback.
• Clean up orphaned MSLS options daily — enabled by default. Processes all active sites in this network through WP-Cron.
• Delete settings when uninstalling the plugin — disabled by default. When enabled, deleting the plugin removes only its network settings. Posts, translation links, and media remain intact. Deactivation preserves settings.

The page remains available when MSLS is inactive. On installations with multiple networks, each network has its own settings and uninstall preference.

Behavior

With global media library integration enabled, the helper replaces the MSLS featured image importer and writes the source post's _thumbnail_id directly to the destination post. It creates no attachment records or image files and replaces an existing destination featured image when the source has one.

Selecting “Do not import” is respected. If the source has no featured image, the destination featured image is preserved. Without MSLS, the import handler is not registered.

With field copying enabled, Quick Create (“Add from Translation”) copies the source post's publication date (post_date and post_date_gmt), slug (post_name), and author (post_author) into the new translation. The source author's network user ID is retained; the helper does not add that user to the destination site or change their roles. The translation remains a draft. WordPress may add a suffix to an occupied slug when publishing. Dates are copied verbatim, so matching site timezones are recommended for consistent local/UTC date interpretation. This requires MSLS with the msls_quick_create_post_data hook.

For these new translations, the modification date is set to the current time while the publication date is retained. Gutenberg infers an unset publication date when a draft's publication and modification dates match; keeping them separate lets it display the copied date immediately, before the first manual save. A source date equal to the creation time (to the second) may still display “Immediately” until a subsequent save.

Content Import also copies these four fields when the destination draft was created during the same request. Importing into a post or draft that already existed before the request preserves its date, slug, and author. The helper tracks new draft IDs in memory, separately for each site; it stores no persistent metadata. This works independently of the selected post-fields importer.

Other MSLS importers, including the separate attachments importer, retain their existing behavior.

Imported text links

Quick Create and the standard Content Import post-fields Duplicating importer rewrite absolute HTTP(S) and protocol-relative <a href> URLs from the source site to the destination site. Paths, query parameters, and fragments are preserved; home paths are mapped for subdirectory networks.

URLs whose decoded path contains /wp-content/uploads/ are excluded, including links around images and links to PDFs. Image src/srcset, block comments, external URLs, relative URLs, and plain-text URLs are unchanged. Translation existence is not checked during import. The separate 404 fallback below can redirect requests to existing original content.

This runs whenever text is imported, including into existing destination posts. Selecting no post-fields import does not rewrite existing content. The source post is not modified. Link rewriting has its own network setting and works independently of media integration and source date/slug/author copying.

On a disposable WordPress installation, run the focused HTML checks from this directory with wp eval-file tests/content-links.php. Also create a translation through Quick Create and import text into an existing draft to verify saved content and the Gutenberg editor (no block validation errors).

Missing translation fallback

When enabled, a frontend GET/HEAD request returning 404 is checked against the configured source site. Only an exact path match to a published, publicly viewable post or page results in an HTTP 302 redirect to its permalink. Query parameters are retained. Both subdomain and subdirectory networks are supported.

The source site itself, uploads, WordPress service paths, previews, feeds, REST requests, and post-ID query requests are excluded. Missing, draft, private, or deleted originals leave the 404 unchanged. This applies to any qualifying 404, not only links created by the importer, and is independent of MSLS availability and the link rewriting setting. The chosen source must be active and belong to the current network. Missing source rewrite rules cause the lookup to be skipped; the helper does not regenerate them during frontend requests.

For a disposable multisite test, run wp eval-file tests/fallback-redirect.php SOURCE_ID TARGET_ID from this directory. Then check actual HTTP responses: an existing original must produce 302 and the correct Location; a missing or unpublished original, uploads, and requests on the source site must not produce a helper redirect. Confirm that published translations still return normally.

Orphaned MSLS options

Daily cleanup inspects only options named exactly msls_NUMBER or msls_term_NUMBER. It deletes the option if its local post or term is absent. For an existing owner, it removes individual language references whose post or term no longer exists on the destination site. An array emptied by this pruning is deleted; valid remaining references retain their original values.

Languages are resolved to active sites in the current network by WPLANG, using MSLS's en_US default for an empty locale. Unknown languages, duplicate locales, malformed values and non-array options with existing owners are preserved. Existing drafts, private posts and trashed posts count as valid objects. Shared attachment records on other sites do not count as local owners.

Whole-option deletion uses MSLS Post/Tax delete() where available, with a WordPress Options API fallback. Partial arrays use update_option() to preserve values and autoload settings; MSLS save() would delete and recreate the row. WordPress object caches are invalidated through these APIs.

The network's main site hosts the daily WP-Cron event. Each invocation processes one active site and up to 100 MSLS option candidates; further batches run at least a minute apart. Deleted, archived and spam sites are skipped. The first run is scheduled one minute after the next request with the plugin enabled. WP-Cron needs traffic on the network's main site or an external cron runner targeting that site, so these are scheduled times. Database errors stop a batch rather than treating owners or translations as missing.

Disabling cleanup removes its scheduled events and progress. Deactivation and uninstall also remove this runtime state, while saved settings follow the uninstall preference. Cleanup works without MSLS being active.

On a disposable multisite, run wp eval-file tests/orphaned-options.php from this directory. This test creates disposable fixtures and performs real option writes.

Changelog

1.1.0

• Add daily cleanup of orphaned msls_NUMBER and msls_term_NUMBER options across active network sites; remove broken translation references while preserving valid links.
• Process up to 100 candidates per WP-Cron batch and resume from a saved cursor.
• Add an enabled-by-default network setting. Remove cleanup events and progress when disabled, deactivated or uninstalled.

Russian localization

Russian metadata translations are included in languages/juliepr-msls-helper-ru_RU.l10n.php. This native PHP translation format requires WordPress 6.5 or later; no .mo file is required. Log notices are supplied and translated by MSLS itself. The plugin name retains its original spelling.

The editable translation source is languages/juliepr-msls-helper-ru_RU.po. To rebuild the PHP translation file using WP-CLI 2.10 or later, run this from the plugin directory:

wp i18n make-php languages/juliepr-msls-helper-ru_RU.po

See the WordPress translation format announcement.