en.md

Custom Post Meta

Retrieve meta values for custom posts, by querying fields metaValue and metaValues.

For security reasons, which meta keys can be queried must be explicitly configured. By default, the list is empty.

Description

Query fields metaValue and metaValues on a custom post, passing the required meta key as field argument key.

For instance, this query retrieves the post's _edit_last meta value (as long as allowed by configuration):

{
  posts {
    id
    editLast: metaValue(key: "_edit_last")
  }
}

Configuring the allowed meta keys

We must configure the list of meta keys that can be queried via the meta fields.

Each entry can either be:

• A regex (regular expression), if it's surrounded by / or #, or
• The full meta key, otherwise

For instance, any of these entries match meta key "_edit_last":

• _edit_last
• /_edit_.*/
• #_edit_([a-zA-Z]*)#

There are 2 places where this configuration can take place, in order of priority:

1. Custom: In the corresponding Schema Configuration
2. General: In the Settings page

In the Schema Configuration applied to the endpoint, select option "Use custom configuration" and then input the desired entries:

Otherwise, the entries defined in the "Custom Post Meta" tab from the Settings will be used:

There are 2 behaviors, "Allow access" and "Deny access":

• Allow access: only the configured entries can be accessed, and no other can
• Deny access: the configured entries cannot be accessed, all other entries can

Performance considerations

Fetching multiple meta keys for the same object requires a single database call.

However, every call to the database involves only 1 object.

When the query involves a large number of results, resolving the query could become slow.