<?php
/*
Plugin Name: ETH Simple Shortlinks
Plugin URI: https://ethitter.com/plugins/
Description: Simple non-GET shortlinks using post IDs
Author: Erick Hitter
Version: 0.5
Author URI: https://ethitter.com/
Text Domain: eth_simple_shortlinks
Domain Path: /languages/
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
class ETH_Simple_Shortlinks {
/**
* PLUGIN SETUP
*/
/**
* Singleton
*/
private static $instance = null;
/**
* Instantiate singleton
*/
public static function get_instance() {
if ( ! is_a( self::$instance, __CLASS__ ) ) {
self::$instance = new self;
}
return self::$instance;
}
/**
* Dummy magic methods
*/
public function __clone() { _doing_it_wrong( __FUNCTION__, __( 'Cheatin’ uh?' ), '0.1' ); }
public function __wakeup() { _doing_it_wrong( __FUNCTION__, __( 'Cheatin’ uh?' ), '0.1' ); }
public function __call( $name = '', $args = array() ) { unset( $name, $args ); return null; }
/**
* Class properties
*/
private $name = 'ETH Simple Shortlinks';
private $slug = 'p';
private $rewrite_rule = null;
private $rewrite_match = null;
private $qv = 'eth-shortlink';
private $plugin_supported = false;
private $supported_post_types = array();
private $supported_post_statuses = array();
/**
* Register plugin's setup action
*/
private function __construct() {
// Build rewrite parts using other class properties
$this->rewrite_rule = '^' . $this->slug . '/([\d]+)/?$';
$this->rewrite_match = 'index.php?p=$matches[1]&' . $this->qv . '=1';
// Basic plugin actions
add_action( 'plugins_loaded', array( $this, 'action_plugins_loaded' ) );
add_action( 'init', array( $this, 'action_init' ) );
}
/**
* Load plugin translations
*/
public function action_plugins_loaded() {
load_plugin_textdomain( 'eth_simple_shortlinks', false, dirname( plugin_basename( __FILE__ ) ) . '/languages/' );
}
/**
* Verify plugin is supported, then register its functionality
*/
public function action_init() {
global $wp_rewrite;
// Plugin won't work if site doesn't use pretty permalinks
if ( empty( $wp_rewrite->permalink_structure ) ) {
add_action( 'admin_notices', array( $this, 'action_add_admin_notices' ) );
} else {
$this->plugin_supported = true;
// Admin notices
add_action( 'admin_notices', array( $this, 'action_add_admin_notices' ) );
// Register rewrite rule
add_rewrite_rule( $this->rewrite_rule, $this->rewrite_match, 'top' );
// Request handling
add_action( 'wp_loaded', array( $this, 'filter_support' ) );
add_filter( 'query_vars', array( $this, 'filter_query_vars' ) );
add_action( 'parse_request', array( $this, 'action_parse_request' ) );
// Shortlink overrides
add_filter( 'get_shortlink', array( $this, 'filter_get_shortlink' ), 10, 2 );
add_action( 'admin_head-edit.php', array( $this, 'add_admin_header_assets' ) );
add_filter( 'post_row_actions', array( $this, 'filter_row_actions' ), 10, 2 );
add_filter( 'page_row_actions', array( $this, 'filter_row_actions' ), 10, 2 );
}
}
/**
* Display admin notices if plugin's requirements aren't met
*/
public function action_add_admin_notices() {
// Notices are only relevant if current user can get to the Permalinks and Plugins options screens
if ( ! current_user_can( 'manage_options') || ! current_user_can( 'activate_plugins' ) ) {
return;
}
// Build notices
$message = '';
if ( $this->plugin_supported ) {
// Check option for the plugin's rule
// The `$wp_rewrite` global will include it in `extra_rules_top` even though it hasn't been saved to the DB, and therefore isn't really active.
$rewrites = get_option( 'rewrite_rules' );
if ( is_array( $rewrites ) && ! array_key_exists( $this->rewrite_rule, $rewrites ) ) {
$message = sprintf( __( 'Please visit the <a href="%1$s">Permalinks</a> settings page to refresh your permalinks. Doing so will add the rules this plugin requires.', 'eth_simple_shortlinks' ), admin_url( 'options-permalink.php' ) );
}
} else {
$message = sprintf( __( 'Please enable <a href="%1$s">pretty permalinks</a>, otherwise disable this plugin as it is not compatible with "Plain" permalinks.', 'eth_simple_shortlinks' ), admin_url( 'options-permalink.php' ) );
}
// Display a notice if one exists
if ( ! empty( $message ) ) {
$message = sprintf( __( '<strong>%1$s</strong>: %2$s', 'eth_simple_shortlinks' ), $this->name, $message );
?><div class="error">
<p><?php echo $message; ?></p>
</div><?php
}
}
/**
* PLUGIN FUNCTIONALITY
*/
/**
* Allow filtering of supported statuses and types
*/
public function filter_support() {
$this->supported_post_statuses = apply_filters( 'eth_simple_shortlinks_allowed_post_statuses', array( 'publish', 'future' ) );
$this->supported_post_types = apply_filters( 'eth_simple_shortlinks_allowed_post_types', array( 'post', 'page' ) );
}
/**
* Add custom query var to those permitted, so it can be detected at `parse_request`
*/
public function filter_query_vars( $qv ) {
$qv[] = $this->qv;
return $qv;
}
/**
* Catch this plugin's requests and issue redirects, otherwise WP will serve content at duplicate URLs
*
* Allows invalid post IDs fall through to WP's 404 handler, or anything else that might intercede
*
* URLs aren't validated in case plugins filter permalinks to point to external URLs
*/
public function action_parse_request( $request ) {
if ( isset( $request->query_vars[ $this->qv ] ) ) {
$dest = get_permalink( $request->query_vars[ 'p' ] );
if ( $dest ) {
wp_redirect( $dest, 301 );
exit;
}
}
}
/**
* Override shortlinks with this plugin's format
*/
public function filter_get_shortlink( $shortlink, $id ) {
if ( empty( $id ) ) {
$_p = get_post();
if ( ! empty( $_p->ID ) ) {
$id = $_p->ID;
}
}
if ( empty( $id ) ) {
return $shortlink;
}
if ( ! $this->is_supported_post_status( get_post_status( $id ) ) ) {
return $shortlink;
}
if ( ! $this->is_supported_post_type( get_post_type( $id ) ) ) {
return $shortlink;
}
return $this->get_shortlink( $id );
}
/**
* Header assets for shortlink in row actions
*/
public function add_admin_header_assets() {
global $typenow;
if ( ! $this->is_supported_post_type( $typenow ) ) {
return;
}
?>
<script type="text/javascript">
jQuery( document ) .ready( function( $ ) {
$( '.row-actions .shortlink a' ).click( function( e ) {
e.preventDefault();
prompt( 'URL:', $( this ).attr('href') );
} );
} );
</script>
<?php
}
/**
* Provide the shortlink in row actions for easy access
*/
public function filter_row_actions( $actions, $post ) {
if ( ! $this->is_supported_post_type( get_post_type( $post ) ) || ! $this->is_supported_post_status( get_post_status( $post ) ) ) {
return $actions;
}
$actions['shortlink'] = '<a href="' . esc_js( $this->get_shortlink( $post->ID ) ) . '">' . __( 'Shortlink' ) . '</a>';
return $actions;
}
/**
* Check if given post type is supported
*/
private function is_supported_post_type( $type ) {
return in_array( $type, $this->supported_post_types );
}
/**
* Check if given post status is supported
*/
private function is_supported_post_status( $status ) {
return in_array( $status, $this->supported_post_statuses );
}
/**
* Utility method for building permlink
*/
public function get_shortlink( $post_id ) {
// Use Core's default when this plugin can't build a link
if ( ! $this->plugin_supported ) {
return wp_get_shortlink( $post_id );
}
return user_trailingslashit( home_url( sprintf( '%s/%d', $this->slug, $post_id ) ) );
}
}
/**
* One instance to rule them all
*/
ETH_Simple_Shortlinks::get_instance();
/**
* Shortcut for using the shortlink outside of this plugin's considerations
*/
function eth_simple_shortlinks_get( $post_id ) {
if ( ! did_action( 'wp_loaded' ) ) {
_doing_it_wrong( __FUNCTION__, __( 'Shortlinks cannot be generated until after <code>wp_loaded</code>; this ensures that all post types are registered.', 'eth_simple_shortlinks' ), '0.3' );
return false;
}
return ETH_Simple_Shortlinks::get_instance()->get_shortlink( $post_id );
}