Save custom post meta, not saving the data

Question

I have created a custom post type with a metabox date from and date to.

Custom post type creation with the call back function of add_events_metaboxes

function event_list_init(){

    $labels = array(
        'name'                  => _x( 'Events', 'post type general name' ),
        'singular_name'         => _x( 'Event', 'post type singular name' ),
        'menu_name'             => _x( 'Events List', 'admin menu' ),
        'name_admin_bar'        => _x( 'Events List', 'add new on admin bar' ),
        'add_new_item'          => __( 'Add New Event' ),
        'new_item'              => __( 'New Event' ),
        'edit_item'             => __( 'Edit Event' ),
        'view_item'             => __( 'View Event' ),
        'all_items'             => __( 'All Events' ),
        'search_items'          => __( 'Search Events' ),
        'not_found'             => __( 'No Events found.' ),
        'not_found_in_trash'    => __( 'No Events found in Trash.' )
    );

    $args   = array(
        'labels'                => $labels,
        'description'           => __( 'Create Events' ),
        'public'                => true,
        'publicly_queryable'    => true,
        'show_ui'               => true,
        'show_in_menu'          => true,
        'query_var'             => true,
        'rewrite'               => array( 'slug' => 'event' ),
        'capability_type'       => 'post',
        'has_archive'           => true,
        'hierarchical'          => true,
        'menu_position'         => 6,
        'register_meta_box_cb'  => 'add_events_metaboxes',
        'menu_icon'             => 'dashicons-calendar-alt',
        'supports'              => array( 'title', 'editor', 'author', 'thumbnail', 'excerpt', 'comments' )
    );

    register_post_type('events',$args);

}

add_action('init','event_list_init');

here is the call back function that instantiate a class to create the metabox and save post data via the action hook save_post

function add_events_metaboxes(){
   new eventsListMetaBox();
}

class eventsListMetaBox{
    /*
     * Constructor that creates the meta box
     */
    public  function  __construct(){
        /**
         * Render and Add form meta box
         */
        add_meta_box('wpt_events_date', 'Events Date', array($this, 'fisa_events_date'), 'events', 'side', 'high');

        /**
         * Save Date from and to as meta key
         */
        add_action('save_post',array($this, 'fisa_events_date_save'),1,2);
    }

    /**
     * Render Form for Events date
     */
    function fisa_events_date() {

        global $post;

        // Add an nonce field so we can check for it later.
        wp_nonce_field( 'events_date_fromto', 'events_datefromto_nonce' );

        // Echo out the field
        echo '<label for="_fisa_date_from">Date From</label>';
        echo '<input id="fisa-event-datefrom" type="text" name="_fisa_date_from"  class="widefat" />';
        echo '<br/><br/>';
        echo '<label for="_fisa_date_to">Date To</label>';
        echo '<input id="fisa-event-dateto" type="text" name="_fisa_date_to" class="widefat" />';

    }

    /**
     * Meta key actual database insertion
     */
    function fisa_events_date_save($post_id){

        /**
         * Check if nonce is not set
         */
//        if (!isset($_POST['events_datefromto_nonce']))
//            return $post_id;
//
//        $nonce = $_POST['events_datefromto_nonce'];
//        /**
//         * Verify that the request came from our screen with the proper authorization
//         */
//        if(!wp_verify_nonce($nonce,'events_date_fromto'))
//            return $post_id;
//
//        //Check the user's permission
//
//        if(!current_user_can('edit_post',$post_id) )
//            return $post_id;

        //Prepare and sanitize the data before saving it
        $events_date =  array(
                            sanitize_text_field( $_POST['_fisa_date_from']),
                            sanitize_text_field($_POST['_fisa_date_to'])
                        );

        update_post_meta($post_id, '_fisa_events_date', $events_date);
    }
}

My problem is I cant see _fisa_events_date meta key in postmeta table of wordpress.Can anyone please point what I have missed or what should I do to be able to save it?

Answer 1

You rely on register_meta_box_cb to display your meta box and to hook save logic into save_post. The problem is that Wordpress runs register_meta_box_cb (which hooks into add_meta_boxes) only when metaboxes need to be displayed - i.e. when the edit or add post pages are visited. But when Wordpress is saving posts, it does not need to display the metaboxes, so register_meta_box_cb, add_events_metaboxes, and your save_post hook never get called.

The simplest solution is to remove your register_meta_box_cb argument, and hook your add_events_metaboxes function to the admin_init event.

add_action('admin_init', 'add_events_metaboxes');

You can do this just under your add_action('init', 'event_list_init') hook.

Find a gist here.

Answer 2

According to the Wordpress documentation, register_meta_box_cb :

will be called when setting up the meta boxes for the edit form.

Which is too late to hook into the save_post.

So I suggest you separately hook into the save_post somewhere in your functions.php file:

Registering post type

$args   = array(
    ....
    'register_meta_box_cb'  => 'add_events_metaboxes',
    ....
);
register_post_type( 'events', $args );

Render the metabox

function add_events_metaboxes(){
   new eventsListMetaBox();
}

class eventsListMetaBox{
    public  function  __construct(){
        add_meta_box('wpt_events_date', 'Events Date', array($this, 'fisa_events_date'), 'events', 'side', 'high');
    }

    function fisa_events_date() {
        ...
    }
}

Saving the metabox

add_action( 'save_post', 'fisa_events_date_save' );

function fisa_events_date_save(){
    global $post;
    $post_id = $post->ID;

    // Use wp_verify_nonce and other checks to verify everything is right

    $events_date =  array(
                        sanitize_text_field( $_POST['_fisa_date_from']),
                        sanitize_text_field($_POST['_fisa_date_to'])
                    );
    update_post_meta($post_id, '_fisa_events_date', $events_date);
}

Please keep in mind that Wordpress is not intended to operate fully Object-Oriented, thus there may be problems using its hooking system with OOP concepts.

Answer 3

As exposed in other answers, the issue is that register_meta_box_cb callback will only deal with the following:

Do remove_meta_box() and add_meta_box() calls in the callback.

save_post is not covered in the callback and has to be independent. This action hook happens:

whenever a post or page is created or updated, which could be from an import, post/page edit form, xmlrpc, or post by email

As you're using a Class to wrap the meta box creation, I'd suggest wrapping everything inside it.
_{PS: check comments and add necessary checks inside save_post callback.}

<?php
class MyEvents {
    public  function  __construct(){
        add_action( 'init', array( $this, 'init' ) );    
        add_action( 'save_post', array( $this, 'save_post' ), 10, 2 ); // no need to change priority to 1
    }

    public function init(){
        $labels = array(
            'name'                  => _x( 'Events', 'post type general name' ),
            'singular_name'         => _x( 'Event', 'post type singular name' ),
            'menu_name'             => _x( 'Events List', 'admin menu' ),
            'name_admin_bar'        => _x( 'Events List', 'add new on admin bar' ),
            'add_new_item'          => __( 'Add New Event' ),
            'new_item'              => __( 'New Event' ),
            'edit_item'             => __( 'Edit Event' ),
            'view_item'             => __( 'View Event' ),
            'all_items'             => __( 'All Events' ),
            'search_items'          => __( 'Search Events' ),
            'not_found'             => __( 'No Events found.' ),
            'not_found_in_trash'    => __( 'No Events found in Trash.' )
        );
        $args   = array(
            'labels'                => $labels,
            'description'           => __( 'Create Events' ),
            'public'                => true,
            'publicly_queryable'    => true,
            'show_ui'               => true,
            'show_in_menu'          => true,
            'query_var'             => true,
            'rewrite'               => array( 'slug' => 'event' ),
            'capability_type'       => 'post',
            'has_archive'           => true,
            'hierarchical'          => true,
            'menu_position'         => 6,
            'register_meta_box_cb'  => array( $this, 'add_metaboxes' ),
            'menu_icon'             => 'dashicons-calendar-alt',
            'supports'              => array( 'title', 'editor', 'author', 'thumbnail', 'excerpt', 'comments' )
        );
        register_post_type('events',$args);
    }

    public function add_metaboxes() {
        add_meta_box( 'wpt_events_date', 'Events Date', array( $this, 'the_metabox' ), 'events', 'side', 'high' );
    }

    public function the_metabox( $post ) { // No need for "global $post", it's passed as parameter
        wp_nonce_field( 'events_date_fromto', 'events_datefromto_nonce' );
        $dates = get_post_meta( $post->ID, '_fisa_events_date', true);
        $from = $dates ? $dates[0] : false;
        $to = $dates ? $dates[1] : false;
        echo '<label for="_fisa_date_from">Date From</label>';
        printf(
            '<input id="fisa-event-datefrom" type="text" name="_fisa_date_from"  class="widefat" value="%s" />',
            $from ? $from : ''
        );
        echo '';
        echo '<br/><br/>';
        echo '<label for="_fisa_date_to">Date To</label>';
        printf(
            '<input id="fisa-event-dateto" type="text" name="_fisa_date_to"  class="widefat" value="%s" />',
            $to ? $to : ''
        );
    }

    public function save_post( $post_id, $post_object ) { // second parameter has useful info about current post
        /* BRUTE FORCE debug */
        // wp_die( sprintf( '<pre>%s</pre>', print_r( $_POST, true ) ) );

        /**
         * ADD SECURITY AND CONTENT CHECKS, omitted for brevity
         */
        if( !empty( $_POST['_fisa_date_from'] ) ) {
            $events_date =  array(
                                sanitize_text_field( $_POST['_fisa_date_from']),
                                sanitize_text_field($_POST['_fisa_date_to'])
                            );
            update_post_meta($post_id, '_fisa_events_date', $events_date);
        }
    }
}
new MyEvents();