Meta Box
Meta Box is a WordPress framework for creating custom fields, custom post types, and custom taxonomies. WP Media Cloud works with Meta Box transparently — no configuration is needed in either plugin. Meta Box stores attachment IDs in postmeta and retrieves URLs through WordPress’s standard attachment functions, which WP Media Cloud already filters to return cloud storage URLs.
How they work together#
Meta Box image and file fields store the WordPress attachment ID in postmeta, not the URL. When Meta Box retrieves a field value and resolves it to a URL for display, it calls WordPress’s standard attachment URL functions. WP Media Cloud filters those functions at the point of output and returns the cloud storage or CDN URL automatically. No changes to your Meta Box field groups, field types, or templates are needed.
This applies across all Meta Box field types that store attachment IDs:
- Image field
- File field
- Image List field
- Image Advanced field
- File List field
- File Advanced field
- Image and file sub-fields inside Group fields
Fields that store plain text, numbers, dates, post relationships, taxonomy terms, or other non-media values are not affected.
Configuration#
No configuration is required. WP Media Cloud detects Meta Box automatically via the RWMB_VER constant and reports its active status on the Integrations tab. There is no Meta Box-specific hook or filter needed — the integration works entirely through WordPress’s core attachment URL layer.
Local file removal#
Unlike ACF, Meta Box does not perform a local filesystem check for file metadata in its standard field retrieval path. Enabling local file removal in WP Media Cloud does not affect how Meta Box resolves or displays attachment URLs. Cloud URLs are returned correctly regardless of whether local copies exist.
Troubleshooting#
Meta Box image field is showing the local URL instead of the cloud URL
Confirm URL rewriting is enabled in WP Media Cloud > Settings. Also confirm the image has been offloaded by going to Media > Library, clicking the image, and checking its URL. If it still shows the local site URL the file has not been offloaded. Run the bulk migration tool to offload existing media.
File List or Image List fields are not returning cloud URLs
These field types return arrays of attachment IDs. WP Media Cloud rewrites each ID’s URL individually via WordPress attachment functions. If some files in a list are not resolving to cloud URLs, confirm each attachment in the list has been individually offloaded in the media library.