wordpress


WordPress: How to disable a plugin on all pages except for a specific one

A few days ago we were struggling to find a way to limit the amount of plugins that load at any point on a WordPress website. We noticed that several plugins enqueue their scripts and their styles in all requests to the website even if they are actually used on a single page only. This issue was important to address as it was making the whole server slower by giving it extra requests from the client that would never provide any actual benefit to the user.

Initially, we tried to selectively enable those plugins on their respective pages but we did not get it right and things would load out of order and break. Instead of following the ‘enable when needed‘ methodology we decided to follow the ‘disable unless needed‘ methodology which seemed simpler at the time.

Our changes involved in adding the following code in the functions.php file of our child theme.

//Register a filter at the correct event
add_filter( 'option_active_plugins', 'bf_plugin_control' );

function bf_plugin_control($plugins) {
  // If we are in the admin area do not touch anything
  if (is_admin()) {
    return $plugins;
  }
  
  // Check if we are at the expected page, if not remove the plugin from the active plugins list
  if(is_page("csv-to-kml-cell-site-map") === FALSE){ 
    // Finding the plugin in the active plugins list
    $key = array_search( 'csv-kml/index.php' , $plugins );
    if ( false !== $key ) {
      // Removing the plugin and dequeuing its scripts
      unset( $plugins[$key] );
      wp_dequeue_script( 'bf_csv_kml_script' );
    }
  }

  if(is_page("random-password-generator") === FALSE){ 
    $key = array_search( 'bytefreaks-password-generator/passwordGenerator.php' , $plugins );
    if ( false !== $key ) {
      unset( $plugins[$key] );
    }
  }
  
  if(is_page("xml-tree-visualizer") === FALSE){ 
    $key = array_search( 'xmltree/xml-tree.php' , $plugins );
    if ( false !== $key ) {
      unset( $plugins[$key] );
      wp_dequeue_script( 'bf_xml_namespace' );
      wp_dequeue_style( 'bf_xml_namespace' );
    }
  }

  return $plugins;
}

One day, we will clean the above code to make it tidy and reusable.. one day, that day is not today.

What the code above does is the following:

  • Using is_admin it checks if the Dashboard or the administration panel is attempting to be displayed, in that case it does not do any changes.
  • With is_page, it will additionally check if the parameter is for one of the pages specified and thus disable the plugin if the check fails.
  • PHP command array_search, will see if our plugin file is expected to be executed (all files in $plugins are the plugin files that are expected to be executed) .
  • wp_dequeue_script and wp_dequeue_style remove the previously enqueued scripts and styles of the plugin as long as you know the handles (or namespaces of the enqueued items).
    To get the handles (namespaces) we went through the plugin codes and found all instances of wp_enqueue_script and wp_enqueue_style.
    Please note that several small plugins do not have additional items in queue so no further action is needed.

Advertisements

Easy way to repair and optimize core WordPress MySql DataBase Tables

To manually repair and optimize the core WordPress tables of your MySql (or MariaDB) database:

A) edit your wp-config.php and add

define('WP_ALLOW_REPAIR', true);

right before the line

/* That's all, stop editing! Happy blogging. */

B) Visit the following link (and replace example.com with the domain or the IP of your site installation)

https://example.com/wp-admin/maint/repair.php

C) Press the Repair and Optimize Database button and wait for some time (depending on the size of the core tables of your installation)

D) Once the above step is done, remove or comment out (by adding a # at the beginning of the line) the line:

define('WP_ALLOW_REPAIR', true);

You need to do this step to to prevent this page (which could potentially take a lot of resources) from being used by unauthorized users.


WordPress Action: Cookie compliance on IEEE websites

Greetings,

If you have been identified as the owner of an IEEE website, you need to be aware of the new European Union (EU) regulation called the General Data Protection Regulation (GDPR) that takes effect on 25 May 2018 and is expected to have a far-reaching impact on how business is conducted worldwide with respect to the collection and use of personal data.

In order to comply with the new regulations, IEEE needs to look at the personal data collected through cookies – such as a user’s personal address, email address, demographic information, and more. As a step toward the direction the GDPR wants IEEE to move to, you need to add an informational banner on your IEEE related websites about cookies.

Following are the instructions to help you apply the informational banner on your WordPress website. The content that feeds to the banner will be managed by IEEE staff. This banner will briefly outline how IEEE uses cookies to enhance the user’s experience, as well as link to the IEEE Privacy Policy for more information.

In the functions.php file of your theme paste the following snippet:

function bytefreaks_header_cookies(){
?>
 <script src="https://s3-us-west-2.amazonaws.com/ieeeshutpages/gdpr/settings.js"></script>
 <link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/cookieconsent2/3.0.3/cookieconsent.min.css" />
 <script src="https://cdnjs.cloudflare.com/ajax/libs/cookieconsent2/3.0.3/cookieconsent.min.js"></script>
 <script>
   window.addEventListener("load", function(){
     window.cookieconsent.initialise(json)
   });
 </script>
<?php
};
add_action('wp_head', 'bytefreaks_header_cookies');

Install Required Plugins of Gillion | Multi-Concept Blog/Magazine & Shop WordPress Theme

For Gillion (the Multi-Concept Blog/Magazine & Shop WordPress Theme) to properly work, it needs the WPBakery Page Builder (formerly Visual Composer) and the Unison plugins. In a clients’ page, they did not get the message prompting to install the required plugins and could not find it again. Unison is available through WordPress Plugin Directory so that was easy to setup. On the other hand, WPBakery (and the Revolution slider) it is not available through the directory as it is a commercial product. After reading through the support forums we realised that they should not need to make a separate purchase of the plugin, the theme will be able to pull it automatically from a CDN of shufflehound (without getting support from the WPBakery team).

Solution: In case you are facing the same issue, you can find the installation link under the left side menu Appearance where a new option will be available called Install Plugins (the link will be similar to this http://example.com/wp-admin/themes.php?page=tgmpa-install-plugins). We installed for them the two required plugins and their theme was operational.

Links:


JetPack: Cannot Verify Site Ownership using pinterest 5

Recently, we tried to verify the ownership of a site running WordPress with JetPack in Pinterest.

As the instructions say, we logged in to Pinterest and visited the settings page to Claim Website paragraph.

Using the meta tag solution we received a code similar to the one below:

<meta name="p:domain_verify" content="8525e3384b3545fb80b9e21f0910de21"/>

When we tried to add the code in the JetPack site verification page (https://example.com/wp-admin/admin.php?page=jetpack#/traffic) we got the following error:
Error updating settings. Invalid parameter(s): pinterest (Status 400).

To resolve the issue, we just added a space character right before the end of the tag /> and our code became:

<meta name="p:domain_verify" content="8525e3384b3545fb80b9e21f0910de21" />

Trying again, it worked properly!


WPML: How to add the Languages’s list in a WordPress menu

The code in this article can be used to create a WPML language switcher that will be attached at the bottom of a specific WordPress menu. Each Language will be a sub-menu item of a new menu item named Languages.

Menu Languages Options

You should add this code to your theme’s functions.php file. It is highly recommended to add this change to the functions.php of child theme.

Choosing which languages to show

By default, the following code will be showing ALL available languages, including the currently active one. We did that as we only have two languages in our website and it would weird to: (a) have only one sub-menu item in the Languages menu item or (b) remove the Languages menu item and place the inactive language item directly on the menu.

To show only the inactive languages, change the line that contains $showActive = true; to $showActive = false;.

Choosing which menu to show the languages on

To choose the menu on which you want the languages to appear in, you need to set the value of $themeLocation = 'main'; to the theme location that the menu has in your current theme.

For the default WordPress themes (Twenty Sixteen, Twenty Fifteen, etc.) setting the value to primary as follows $themeLocation = 'primary'; will add the languages to the main menu.

For the customizr theme (this also works for the pro version),  setting the value to main as follows $themeLocation = 'main'; will add the languages to the main menu.

For other themes, you need to find the name of the menu you want to append the languages to. To do so change the line $showMenuName = false; to $showMenuName = true;. This will print at the beginning of your menu the location of the menu inside the theme using a <pre> tag. Copy that value to the $themeLocation variable, change the $showMenuName back to $showMenuName = false; and you are done.

Menu Location

/* Add languages menu to main menu */
add_filter('wp_nav_menu_items', 'new_nav_menu_items', 10, 2);
function new_nav_menu_items($items, $args) {
    
    $showActive = true;
    $themeLocation = 'main';
    $showMenuName = false;

    if ($showMenuName) {
        echo "<pre>"; print_r(get_object_vars($args)['theme_location']); echo "</pre>";
    }

    // get languages
    $languages = apply_filters( 'wpml_active_languages', NULL, 'skip_missing=0' );

    if ( $languages && $args->theme_location == $themeLocation) {

        if(!empty($languages)){

            $items = $items . '<br/><li class="menu-item">Languages';
            $items = $items . '<ul class="dropdown-menu">';
            foreach($languages as $l){

                if(!$l['active'] || $showActive){
                    $items = $items . '<li class="menu-item"><a href="' . $l['url'] . '"><img src="' . $l['country_flag_url'] . '" height="12" alt="' . $l['language_code'] . '" width="18" /> ' . $l['native_name'] . '</a></li>';
                }
            }
            $items = $items . '</li></ul>';
        }
    }

    return $items;
}

The above code was generated using the documentation examples of WPML.


Create a sortable ‘Modified Date’ sortable column for posts and pages in wordpress admin area 6

2016-07-14: Post updated to support both pages and posts without redundant/useless code

Paste the following in the functions.php file of your theme:

// Register the column for modified date
function bf_post_modified_column_register( $columns ) {
    $columns['post_modified'] = __( 'Modified Date', 'mytextdomain' );
    return $columns;
}
add_filter( 'manage_edit-post_columns', 'bf_post_modified_column_register' );
add_filter( 'manage_edit-page_columns', 'bf_post_modified_column_register' );

// Display the modified date column content
function bf_post_modified_column_display( $column_name, $post_id ) {
    if ( 'post_modified' != $column_name ){
        return;
    }
    $post_modified = get_post_field('post_modified', $post_id);
    if ( !$post_modified ){
        $post_modified = '' . __( 'undefined', 'mytextdomain' ) . '';
    }
    echo $post_modified;
}
add_action( 'manage_posts_custom_column', 'bf_post_modified_column_display', 10, 2 );
add_action( 'manage_pages_custom_column', 'bf_post_modified_column_display', 10, 2 );

// Register the modified date column as sortable
function bf_post_modified_column_register_sortable( $columns ) {
    $columns['post_modified'] = 'post_modified';
    return $columns;
}
add_filter( 'manage_edit-post_sortable_columns', 'bf_post_modified_column_register_sortable' );
add_filter( 'manage_edit-page_sortable_columns', 'bf_post_modified_column_register_sortable' );

When you refresh http://<Your Domain>/wp-admin/edit.php or http://<Your Domain>/wp-admin/edit.php?post_type=page the ‘Modified Date’ column will be visible and sortable.


Include more filetypes to a WordPress Installation Media Library

In the folder <Installation Path>/wp-includes/ there is a file called functions.php, inside this file there is a function called get_allowed_mime_types().
This function is in charge of defining an Array of mime types keyed by the file extension with a regex corresponding to those types.

So in order to add a new file-type to the white-list you just have to add a new line with the following format in the list:

'jpg|jpeg|jpe' => 'image/jpeg',

Where, on the left you define the extensions you want to be accepted separated by the vertical bar character (“|”) and on the right you give a file definition.