How to Create a Custom WordPress Plugin From Scratch: A Developer's Guide

Have you ever wanted to customize WordPress beyond its themes and existing plugins? Creating your own plugin opens up a world of possibilities to tailor your website to your exact needs. This guide will walk you through the process, tools, and best practices to build a WordPress plugin from scratch.

1. What You Need Before You Begin

Before diving into code, set up your development environment:

• Local WordPress Installation: Use tools like Local by Flywheel, XAMPP, or MAMP.
• Code Editor: Tools like VS Code or PhpStorm.
• Version Control: Git for managing your code.
• PHP Knowledge: A solid understanding of PHP is essential.
• Basic WordPress Concepts: Know what hooks, actions, filters, and shortcodes are.

2. Planning Your Plugin

Define the purpose of your plugin:

• What problem does it solve?
• What features will it include?
• How will it integrate with WordPress?

Example: Let’s build a "Simple Testimonials" plugin that allows users to submit and display testimonials. We will create the plugin together step by step.

3. Creating the Plugin Boilerplate

a. Setting Up the Plugin Folder

In your local WordPress installation, navigate to:

/wp-content/plugins/

Create a folder for your plugin:

simple-testimonials.

b. Creating the Main Plugin File

Inside the folder, create a file:

simple-testimonials.php

Add the header information:

<?php
/**
 * Plugin Name: Simple Testimonials
 * Description: A plugin to manage and display user testimonials.
 * Version: 1.0.0
 * Author: [Your Name]
 * License: GPL2
 */

4. Adding Core Features

a. Registering a Custom Post Type

Use WordPress’s built-in register_post_type() function for testimonials:

function st_register_testimonial_cpt() {
    register_post_type('testimonial', [
        'label' => 'Testimonials',
        'public' => true,
        'supports' => ['title', 'editor'],
        'menu_icon' => 'dashicons-testimonial',
    ]);
}
add_action('init', 'st_register_testimonial_cpt');

b. Creating a Shortcode

Allow users to display testimonials with a shortcode:

function st_testimonials_shortcode($atts) {
    $query = new WP_Query(['post_type' => 'testimonial']);
    $output = '<div class="testimonials">';
    while ($query->have_posts()) {
        $query->the_post();
        $output .= '<blockquote>' . get_the_content() . '</blockquote>';
        $output .= '<p>— ' . get_the_title() . '</p>';
    }
    $output .= '</div>';
    wp_reset_postdata();
    return $output;
}
add_shortcode('testimonials', 'st_testimonials_shortcode');

5. Enhancing the Plugin

a. Adding a Settings Page

Use the WordPress Settings API to allow users to configure the plugin.

function st_add_settings_page() {
    add_options_page(
        'Simple Testimonials Settings',
        'Testimonials Settings',
        'manage_options',
        'st-settings',
        'st_render_settings_page'
    );
}
add_action('admin_menu', 'st_add_settings_page');

function st_render_settings_page() {
    echo '<h1>Simple Testimonials Settings</h1>';
    // Settings form code here
}

b. Enqueuing Styles and Scripts

Use wp_enqueue_script and wp_enqueue_style for custom CSS/JS:

function st_enqueue_assets() {
    wp_enqueue_style('st-styles', plugin_dir_url(__FILE__) . 'css/style.css');
}
add_action('wp_enqueue_scripts', 'st_enqueue_assets');

6. Testing and Debugging

• Use Query Monitor for debugging.
• Test in different environments to ensure compatibility.

7. Packaging Your Plugin

When you're ready to distribute your plugin:

• Compress the plugin folder into a .zip file.
• Submit it to the WordPress Plugin Directory or share it privately.

Congratulations! You’ve created a WordPress plugin from scratch.

Would you like me to expand on any section?
Leave your thoughts and suggestion in the comment section, we're always together in this journey😊