get_posts() interrupt because of filter

Question

There is a filter on my list-view page of my custom post type (works)

add_action( 'pre_get_posts', array($this, 'exclude_category') );

public function exclude_category( $query){    
       if( is_admin() &&  isset( $_GET['cta_filter']) && ! empty( $_GET['cta_filter'] ) )
        {
            $term =  sanitize_text_field( $_GET['cta_filter'] );

            $query->tax_query->queries[] = array(
                'taxonomy' => 'cta_tax',
                'field'    => 'slug',
                'terms'    => array( $term ),
                'operator' => 'IN'
            );

            $query->query_vars['tax_query'] = $query->tax_query->queries;
        }
}

On the same page where i filter this posts i use get_posts() and it gives me only filtered posts but should return all posts. How can i prevent filtering my posts when i use get_posts() function.

Answer 1

Check that the current query is the main query using $query->is_main_query().

add_action( 'pre_get_posts', array($this, 'exclude_category') );

public function exclude_category( $query){    
    if( is_admin() && $query->is_main_query() && isset( $_GET['cta_filter']) && ! empty( $_GET['cta_filter'] ) ) {
        $term = sanitize_text_field( $_GET['cta_filter'] );

        $tax_query = $query->get('tax_query') ?: array();

        $tax_query[] = array(
            'taxonomy' => 'cta_tax',
            'field'    => 'slug',
            'terms'    => array( $term ),
            'operator' => 'IN'
        );

        $query->set('tax_query',$tax_query):
    }
}

I'm assuming ?cta_filter= is only going to be set on your post type's admin page so no further conditions are necessary, but to be even safer you might want to add another condition:

&& 'post_type_name' === $query->get( 'post_type' )

Also note another change I made to your code. Rather than modifying query properties directly, I suggest using the get() and set() methods.