filter posts by meta key with pagination

Question

Trying to filter out specific posts that have certain meta_key from the main query... problem is it doesnt work with pagination which is my issue here.

Anyone knows how to solve this?

$paged = (end( explode( '/', $_SERVER['REQUEST_URI'] ) )) ? end( explode( '/', $_SERVER['REQUEST_URI'] ) ) : 1;
$posts_per_page = 10;
$offset = ($paged-1) * $posts_per_page;     
function strip_codes_deals ($where = '', $ignore_posts) {
    global $wpdb, $ignore_posts;
    if (count($ignore_posts) > 0) {
        $where .= ' AND ' . $wpdb->posts . '.ID NOT IN(' . implode (',', $ignore_posts) . ') ';
    }
    //echo $where;
    return $where;
}
$wp_query = new WP_query( 'post_type=deals&orderby=date&order=desc&posts_per_page='.$posts_per_page.'&paged='.$paged.'&meta_key=codes-deal' );
//          echo '<pre>';
//          print_r($wp_query);
//          echo '</pre>';
$ignore_posts = array();
if($wp_query) {
    foreach ($wp_query->posts as $post) {
        $codes_deal = get_post_meta($post->ID, "codes-deal", true);
        if($codes_deal == 1) {
            $ignore_posts[] = $post->ID;
        }
    }
    echo '<pre>';
    print_r($ignore_posts);
    echo '</pre>';              
}               
add_filter( 'posts_where', 'strip_codes_deals' );
query_posts( $query_string . '&post_type=deals&orderby=date&order=desc&posts_per_page='.$posts_per_page.'&paged='.$paged );
remove_filter( 'posts_where', 'strip_codes_deals' );

This works for the first page, but all other pages are ignored. Any ideas how to fix this?

Answer 1

You are doing a few different things wrong-- or at least convoluted and suspect-- in that code and I am sure that that is resulting in your query results getting out of sync with the pagination. You've got a couple of queries in there, including one made by query_posts which you should really never be using at all, plus some filters. Honestly, I didn't crawl through it to work out exactly what is wrong but I believe that, primarily what you need is a meta query.

$paged = (get_query_var('paged')) ? get_query_var('paged') : 1;
$args = array(
    'post_type' => 'deals',
    'meta_query' => array(
        array(
            'key' => 'codes-deal',
            'compare' => 'EXISTS'
        )
    ),
    'paged' => $paged 
);
$query = new WP_Query( $args );

Secondarily, you need to clean up your pagination. See the first line. I can't tell if you actually want to filter out posts that "that have certain meta_key" as you stated or if you want to filter the ones with 'codes-deals' = true but I went with what you said. You can edit in your other parameters-- orderby, etc. Be aware that 'compare' => 'EXISTS' only works in 3.5 or better.

That code is almost a copy/paste from the Codex. All I did was edit in some of your values. The Codex is your friend. Love it.

Now, to apply that to the main query. For that you need pre_get_posts, which is a lot more convenient than trying to manipulate the WHERE clause with the post_where filter.

function exclude_codes_deals_wpse_92268($qry) {
    if (is_main_query()) {
        $qry->set('meta_query', array(array(
             'key' => 'codes-deal',
             'compare' => 'EXISTS'
        )));
        $qry->set('post_type', 'deals');
    }
}
add_filter('pre_get_posts','exclude_codes_deals_wpse_92268');

Untested but I believe I have that right. Again, you can edit in any other parameters you need.

That will globally alter your main query, which is what you said you wanted to do, but I have my doubts. With that code in place only the 'deals' post type will show up, unless you specifically create queries to pull other content. I suspect that there are other conditions for altering the query besides just that it is the main query.