Wordpress transients with dynamically generated name as parameter in function

Question

hopefully you can help me with this scenario:

I have several queries of different post types inside shortcode function. Now I´m trying to store those queries with transients. But those transients need to have a unique name for each page from where the shortcode is called.

$trans_posts_golfcourse_ = 'trans_posts_golfcourse_'.$landingpage;

if( false === ( $$trans_posts_golfcourse_ = get_transient( 'trans_posts_golfcourse_' ) ) ) {

    $args = array (
        'posts_per_page'=> 5,
        'post__in'      => $posts_golfcourse,
        'post_type'     => 'golfcourse',
        'post_status'   => 'publish',
        'cache_results' => false,
    );

    $$trans_posts_golfcourse_ = new WP_Query( $args );

    set_transient( 'trans_posts_golfcourse_', $$trans_posts_golfcourse_, 60*60*4 );
}

The dynamically generated variable name is

$$trans_posts_golfcourse_

But how does this have to look like as a parameter?:

get_transient( 'trans_posts_golfcourse_' )

Thanks in advance!

EDIT: found solution for dynamic variable as parameter The parameter(string) has to be generated the same way as the variable name:

 get_transient( 'trans_posts_golfcourse_'.$landingpage )

complete code:

$trans_posts_golfcourse_ = 'trans_posts_golfcourse_'.$landingpage;
if( false === ( ${$trans_posts_golfcourse_} = get_transient( 'trans_posts_golfcourse_'.$landingpage ) ) ) {

    $args = array (
        'posts_per_page'=> 5,
        'post__in'      => $posts_golfcourse,
        'post_type'     => 'golfcourse',
        'post_status'   => 'publish',
        'cache_results' => false,
    );

    ${$trans_posts_golfcourse_} = new WP_Query( $args );

    set_transient( 'trans_posts_golfcourse_'.$landingpage, ${$trans_posts_golfcourse_}, 60*60*4 );
}

EDIT: Transient is not reducing queries, although transient seems to be called correctly. Does anybody have an idea?

Answer 1

The solution is to put the query and the loop inside a transient. Two methods are possible:

1. Inside a function (shortcode f.e.)

       function get_content( $dynamic_var ){
           $transient_time = 60*60*4;
           $transient_name = "transient_name_" . $dynamic_var;
   
           $content = get_transient( $transient_key );
           if( !empty($content)  ) { return $content; }
   
           $args = array ('');
           $query = new WP_Query( $args );
   
           $content = '';
           if( $query->have_posts() ):
               while( $query->have_posts() ) : $query->the_post();
                   $content.= 'some_content';
               endwhile; wp_reset_postdata();
           endif;
   
           set_transient( $transient_name, $content, $transient_time );
           return $content;
       }
   

2. Inside a template

           $transient_time = 60*60*4;
           $transient_name = 'transient_name_' . $page_id;
           // ${$transient_name} > name of variable is dynamically created by
           // the value of variable $transient_name (search for > php variable variables)
   
           $content = '';
           if( false === ( ${$transient_name} = get_transient( $transient_name ) ) ) {
               $args = array ('');
               $query = new WP_Query( $args );
   
               $content_inner = '';
               if( $query->have_posts() ):
                   while( $query->have_posts() ) : $query->the_post();
                       $content_inner.= 'some_content';
                   endwhile; wp_reset_postdata();
               endif;
   
               set_transient( $content_inner, ${$transient_name}, $transient_time );
           }
           $content.= ${$transient_name};