Venue meta data and metaboxes

Since 1.4 the venue table has been converted into a metadata table – that is, it follows the same structure as the post meta, user meta etc tables. Each row has its own meta ID, a venue (term) ID, a meta key and a meta value.

Naming conventions

To ‘future proof’ your metadata, it’s advised that you precede your keys with an underscore. For instance, use the meta key, _opening_time rather than opening_time.

Adding metabox onto the venue page

Adding a metabox to the venue page is (almost) identical to adding a metabox to a post type. To add a metabox you can use the usual add_meta_boxes action or the add_meta_boxes_event_page_venues action, following the WordPress standard of add_meta_boxes_{$screen_id}. Inside that hooked callback you add the metabox by calling add_meta_box. Where the $post_type (or screen ID) is set to event_page_venues

For instance

 add_action('add_meta_boxes','my_add_metabox');
 function my_add_metabox(){
      add_meta_box('my_id','My Title', 'my_metabox_callback', 'event_page_venues', 'side', 'high');
 }
 function my_metabox_callback( $venue ){
    //Metabox's innards:
    $time = eo_get_venue_meta($venue->term_id, '_opening_times',true);

    //Remember to use nonces!
    wp_nonce_field('my_venue_meta_save', 'my_plugin_nonce_field' );
    ?>
    <label> Opening times:</label> 
    <input type="text" name="my_opening_time" value="<?php echo esc_attr($time);?>" >
    <?php
 }

Saving and retrieving meta data.

Rather than hooking onto save_post its preferable to hook onto eventorganiser_save_venue. You can then proceed ‘as normal’ (as you would with save_post): checking nonces, permissions, and collecting your metaboxes data from $_POST:

add_action ('eventorganiser_save_venue','my_save_venue_meta');
function my_save_venue_meta( $venue_id ){

    //If our nonce isn't present just silently abort.    
    if( !isset( $_POST['my_plugin_nonce_field'] ) )
        return;

    //Check permissions
    $tax = get_taxonomy( 'event-venue');
    if ( !current_user_can( $tax->cap->edit_terms ) )
        return;

    //Check nonce
    check_admin_referer( 'my_venue_meta_save', 'my_plugin_nonce_field' );

    //Retrieve meta value(s)
    $value = $_POST['my_opening_time'];

    //Update venue meta
    eo_update_venue_meta($venue_id,  '_opening_times', $value);
    return;
}

The following functions are almost identical to get_post_meta, add_post_meta, update_post_meta, delete_post_meta. In all instances the arguments are same – except rather than a post ID you pass the venue (term) ID.

• eo_get_venue_meta($venue_id, $key, $single)
• eo_add_venue_meta($venue_id, $key, $value, $unique )
• eo_update_venue_meta($venue_id, $key, $value, $prev_value)
• eo_delete_venue_meta($venue_id, $key, $value, $delete_all )

Reserved meta keys:

The following keys are used by the plug-in, so in order not to cause unwanted behaviour please avoid them: _address, _postcode,_country,_lat,_lng,_description