如何在 WordPress 多站点中显示最近的全局帖子

我在 ayp.no 上运行一个 wordpress 多站点，我正在尝试找出一种方法来呈现所有子站点的徽标和所有博客的最新帖子，我知道有一个 wpmudev 高级插件，但我希望有一些编码我可以自己做（好吧，显然不是我自己，但至少在这里问一下并看看）..

首先，我们需要一个获取所有站点的函数 https://wordpress.stackexchange.com/a/114749/12615，有了这个，我们就可以迭代站点数组并使用以下命令提取信息wp_get_recent_posts() http://codex.wordpress.org/Function_Reference/wp_get_recent_posts（这是一个定制版本get_posts() http://codex.wordpress.org/Template_Tags/get_posts).

使用以下内容作为必须使用插件 http://codex.wordpress.org/Must_Use_Plugins，所以函数b5f_print_recent_posts()可在整个网络中使用：

<?php
/**
 * Plugin Name: Recent Network Posts
 * Plugin URI: http://stackoverflow.com/q/23713801/1287812
 * Description: Creates a function that lists recent posts from all sites of the network. Call it in another plugins or themes.
 * Author: brasofilo   
 */

/**
 * Iterates throught all sites of the network and grab the recent posts
 */
function b5f_print_recent_posts()
{
    $blogs = b5f_get_blog_list( 0, 'all', true );
    $current_blog_id = get_current_blog_id();
    foreach( $blogs as $blog ) 
    {
        switch_to_blog( $blog[ 'blog_id' ] );
        echo '<h3>' . $blog['name'] . ' - ' . $blog['domain'] . ' - ' . $blog['desc'] . '</h3>';
        $posts = wp_get_recent_posts( array(), OBJECT );
        if( $posts )
        {
            foreach( $posts as $post )
            {
                printf(
                    '- <a href="%s">%s</a><br />',
                    get_permalink( $post->ID ),
                    $post->post_title
                );
            }
        }
    }
    switch_to_blog( $current_blog_id );
}

/**
 * Returns an array of arrays containing information about each public blog 
 * hosted on this WPMU install.
 * 
 * Only blogs marked as public and flagged as safe (mature flag off) are returned.
 *
 * @author Frank Bueltge
 * 
 * @param   Integer  The first blog to return in the array.
 * @param   Integer  The number of blogs to return in the array (thus the size of the array).
 *                   Setting this to string 'all' returns all blogs from $start
 * @param   Boolean  Get also Postcount for each blog, default is False for a better performance
 * @param   Integer  Time until expiration in seconds, default 86400s (1day)
 * @return  Array    Returns an array of arrays each representing a blog. 
 *                   Details are represented in the following format:
 *                       blog_id   (integer) ID of blog detailed.
 *                       domain    (string)  Domain used to access this blog.
 *                       path      (string)  Path used to access this blog.
 *                       postcount (integer) The number of posts in this blog.
 *                       name      (string) Blog name.
 *                       desc      (string) Blog description.
 */
function b5f_get_blog_list( $start = 0, $num = 10, $details = FALSE, $expires = 86400 ) {

    // get blog list from cache
    $blogs = get_site_transient( 'multisite_blog_list' );

    // For debugging purpose
    if ( defined( 'WP_DEBUG' ) && WP_DEBUG )
        $blogs = FALSE;

    if ( FALSE === $blogs ) {

        global $wpdb;

        // add limit for select
        if ( 'all' === $num )
            $limit = '';
        else
            $limit = "LIMIT $start, $num";

        $blogs = $wpdb->get_results(
            $wpdb->prepare( "
                SELECT blog_id, domain, path 
                FROM $wpdb->blogs
                WHERE site_id = %d 
                AND public = '1' 
                AND archived = '0' 
                AND mature = '0' 
                AND spam = '0' 
                AND deleted = '0' 
                ORDER BY registered ASC
                $limit
            ", $wpdb->siteid ), 
        ARRAY_A );

        // Set the Transient cache
        set_site_transient( 'multisite_blog_list', $blogs, $expires );
    }

    // only if usable, set via var
    if ( TRUE === $details ) {

        $blog_list = get_site_transient( 'multisite_blog_list_details' );

        // For debugging purpose
        if ( defined( 'WP_DEBUG' ) && WP_DEBUG )
            $blog_list = FALSE;

        if ( FALSE === $blog_list ) {

            global $wpdb;
            $current_blog_id = get_current_blog_id();
            foreach ( (array) $blogs as $details ) {
                $blog_list[ $details['blog_id'] ] = $details;
                $blog_list[ $details['blog_id'] ]['postcount'] = $wpdb->get_var( "
                    SELECT COUNT(ID) 
                    FROM " . $wpdb->get_blog_prefix( $details['blog_id'] ). "posts 
                    WHERE post_status='publish' 
                    AND post_type='page'" 
                );
                switch_to_blog( $details['blog_id'] );
                $blog_list[ $details['blog_id'] ]['name'] = get_blog_details()->blogname;
                $blog_list[ $details['blog_id'] ]['desc'] = get_bloginfo( 'description' );
            }
            switch_to_blog( $current_blog_id );
            // Set the Transient cache
            set_site_transient( 'multisite_blog_list_details', $blog_list, $expires );
        }
        unset( $blogs );
        $blogs = $blog_list;
    }

    if ( FALSE === is_array( $blogs ) )
        return array();

    return $blogs;
}

您可以在之前的插件中添加以下网络仪表板小部件来测试它：

add_action( 'wp_network_dashboard_setup', 'dashboard_setup_so_23713801' );

function dashboard_setup_so_23713801() 
{
    wp_add_dashboard_widget( 'widget_so_23713801', __( 'Test widget' ), 'print_widget_so_23713801' );
}

function print_widget_so_23713801() 
{
    b5f_print_recent_posts();
}