/* Plugin Name: Random Redirect Plugin URI: https://wordpress.org/extend/plugins/random-redirect/ Description: Allows you to create a link to yourblog.example.com/?random which will redirect someone to a random post on your blog, in a StumbleUpon-like fashion. Version: 1.2-wpcom Author: Matt Mullenweg Author URI: http://photomatt.net/ */ function jetpack_matt_random_redirect() { // Verify that the Random Redirect plugin this code is from is not active // See http://plugins.trac.wordpress.org/ticket/1898 if ( ! ( defined( 'IS_WPCOM' ) && IS_WPCOM ) ) { require_once( ABSPATH . 'wp-admin/includes/plugin.php' ); if ( is_plugin_active( 'random-redirect/random-redirect.php' ) ) return; } // Set default post type. $post_type = get_post_type(); // Set default category type if ( is_category() ) { $category = get_the_category(); if ( isset( $category ) && ! empty( $category ) ) { $random_cat_id = $category[0]->term_id; } } // Set author name if we're on an author archive. if ( is_author() ) { $random_author_name = get_the_author_meta( 'user_login' ); $random_author_query = 'AND user_login = "' . $random_author_name . '"'; } else { $random_author_query = ''; } // Acceptable URL formats: /[...]/?random=[post type], /?random, /&random, /&random=1 if ( ! isset( $_GET['random'] ) && ! in_array( strtolower( $_SERVER['REQUEST_URI'] ), array( '/&random', '/&random=1' ) ) ) return; // Ignore POST requests. if ( ! empty( $_POST ) ) return; // Persistent AppEngine abuse. ORDER BY RAND is expensive. if ( strstr( $_SERVER['HTTP_USER_AGENT'], 'AppEngine-Google' ) ) wp_die( 'Please contact support' ); // Set the category ID if the parameter is set. if ( isset( $_GET['random_cat_id'] ) ) $random_cat_id = (int) $_GET['random_cat_id']; // Change the post type if the parameter is set. if ( isset( $_GET['random_post_type'] ) && post_type_exists( $_GET['random_post_type'] ) ) $post_type = $_GET['random_post_type']; // Don't show a random page if 'page' isn't specified as the post type specifically. if ( 'page' === $post_type && is_front_page() && ! isset( $_GET['random_post_type'] ) ) { $post_type = 'post'; } global $wpdb; if ( isset( $random_cat_id ) ) { $random_id = $wpdb->get_var( $wpdb->prepare( "SELECT DISTINCT ID FROM $wpdb->posts AS p INNER JOIN $wpdb->term_relationships AS tr ON (p.ID = tr.object_id AND tr.term_taxonomy_id = %s) INNER JOIN $wpdb->term_taxonomy AS tt ON(tr.term_taxonomy_id = tt.term_taxonomy_id AND taxonomy = 'category') WHERE p.post_type = %s AND post_password = '' AND post_status = 'publish' %s ORDER BY RAND() LIMIT 1", $random_cat_id, $post_type, $random_author_query ) ); } else { $random_id = $wpdb->get_var( $wpdb->prepare( "SELECT ID FROM $wpdb->posts WHERE post_type = %s AND post_password = '' AND post_status = 'publish' %s ORDER BY RAND() LIMIT 1", $post_type, $random_author_query ) ); } $permalink = get_permalink( $random_id ); wp_safe_redirect( $permalink ); exit; } add_action( 'template_redirect', 'jetpack_matt_random_redirect' );