REST - getting all taxonomy terms with one GET request causes division by zero warning.

[tmuikku]

Querying taxonomy terms from REST API one can affect the returned items number by using per_page REST argument, like so:
wp-json/wp/v2/customtaxonomy?per_page={number}

Minimum value for this argument is 1, which is annoying in the taxonomy terms context. One have to use a filter to change per_page minimum value to 0 to be able to get all terms at once.

The per_page argument for taxonomy terms route is set in WP_REST_Terms_Controller parent WP_REST_Controller, see get_collection_params() method.

Here is an filter example to allow per_page value 0:

<?php
add_filter( "rest_customtaxonomy_collection_params", 'myplugin_rest_customtaxonomy_collection_params_filter');
function myplugin_rest_customtaxonomy_collection_params_filter($query_params) {
        
    $query_params['per_page']['minimum'] = 0;
            
    return $query_params;
}

Now all terms are returned with GET request:
wp-json/wp/v2/customtaxonomy?per_page=0

But now a PHP warning "Division by zero" emerges in
wp-includes/rest-api/endpoints/class-wp-rest-terms-controller.php:271

Please, fix the division by zero warning.
Preferably, also set the per_page minimum value to 0 in WP_REST_Terms_Controller::get_collection_params()

Thanks!

[TimothyBlynJacobs]

Hi @tmuikku,

Apologies for the delay in providing a response.

The REST API does not support unbounded pagination. Instead, it is recommended to query through subsequent pages or increasing the maximum to a value that works for your website.

This was discussed at length during the Gutenberg project. I think this PR is a good jumping off place to read more about the discussion: ​https://github.com/WordPress/gutenberg/pull/10762