How to Develop a New WordPress Plugin? (From Development to Deployment)

WordPress provides an official repository containing more than 59K plugins that assist with a variety of functionalities. Whether you wish to include a simple contact form or make your site an eCommerce store, there will be a plugin for it. But what if you desire a plugin that is customized to your site needs?

Well, you can develop a new WordPress plugin that meets your required site requirements effectively. However, for the best custom-made plugin, good coding skills alone are not sufficient. Plugin creation involves a systematic approach, from research and planning to design and development and then roll-out.

So in this blog, I will tell you how a professional WordPress development company develops a custom product from the website and what you can do for optimal results. Without further delay, let’s get started.

Basics of Plugin Development

Plugins are, basically, PHP scripts meant to extend a WordPress website’s functionalities. Let’s discuss a few fundamental concepts with respect to plugin development.

Plugin Structure

First off, there’s a PHP file containing the plugin’s header comment. WordPress uses this comment to identify the plugin. This file is usually named the same as the plugin’s directory.

Ideally, you should create a separate directory for your new plugin within the wp-content/plugins/ directory. If you have multiple files, subdirectories, or assets, this dedicated directory will help organize the plugin files with ease.

Plugin Header

Again, there’s a header comment block in every plugin’s main PHP file. It gives essential info about the plugin, like its name, version, description, author, etc.

WordPress Hooks

Every WordPress plugin has two hooks: Action Hooks and Filter Hooks.

With Action hooks, you execute the plugin’s specific functionalities at particular points of the site execution flow. You can add and alter a functionality in your plugin through the action hook function add_action(). After it’s triggered, you’ll need to execute the ‘Callback’ function.

Here’s an example of how you use it.

function custom_callback_function( $post_id ) {

   //do something here

}

add_action( 'save_post','custom_callback_function' );

And with Filter hooks, you can edit and modify the data used by WordPress and other plugins. To define filters, you will have to use the function add_filter(). For example, a filter hook can help you change a post’s content before it’s displayed on the live site.

Here’s an example of how you use it.

function change_title_callback( $title ) {

    // modify $title and return a new value.

    return $title;

}

add_filter( 'the_title', 'change_title_callback' );

You must have a good handle on these particulars of a WordPress plugin if you want to create a new one. Otherwise, it will be better to consult with a professional.

Requirements for Creating a New WordPress Plugin

Assuming you already have WordPress installed, let’s count down the requirements.

A Strong PHP Understanding

WordPress is coded in PHP. So PHP is the main language to develop plugins. You need to know its syntax, object-oriented concepts, and best practices. Knowledge of how PHP interacts with databases such as MySQL, supported by WordPress, is essential.

WordPress Basics

It’s extremely essential you know the fundamentals of how WordPress operates. That includes the directory structure of WordPress, schema of the database, theme and plugin concept. In addition to, request handling and page serving within WordPress.

A basic know-how of HTML, CSS, and JavaScript

Even if the core logic of a plugin is done in PHP, you’ll most likely need HTML to construct structure for content. Additionally, there is CSS for aesthetics and JavaScript for dynamic interactions.

Local WordPress Development Environment

Rolling on a live site directly is not safe. You can test your plugin without endangering a production site by utilizing a local environment. XAMPP, MAMP, or Docker are programs that enable you to install WordPress locally on your machine.

Code Editor or IDE

A proper code editor or IDE is a basic necessity. Using it can ease the development and speed up the process. Editors like Visual Studio Code and Sublime text help with tasks like syntax highlighting, code completion and debugging support.

WordPress Hooks (Actions and Filters)

As discussed previously, WordPress hooks form the building blocks of plugins. You will need to know how to leverage action hooks for running code at particular points and filter hooks so that you can manipulate data.

Version Control With Git

Using Git is basically the most talked about tool for a version control system. It helps in keeping track of changes in your codes. You can restore an earlier state whenever needed and enable group collaboration if working as a team. You could have repositories hosted in sites like GitHub, GitLab, or Bitbucket for instance.

WordPress Coding Standards

WordPress coding standards keep the code uniform and identical between the base codes while making it useful and readable. These include PHP codes, HTML, CSS, and JavaScript coding standards.

After you have these requirements down, it’s time to start building a new WordPress plugin.

How to Develop a New WordPress Plugin?

Different plugins require different levels of coding and development. But almost all of them follow a similar development approach. Here, we will look at basic plugin development and deployment.

Step 1: Create Your Plugin File

On your staging or local WordPress development environment, create a folder for the plugin in your site’s directory. Access the site’s files and folder through an FTP client (like FileZilla) or using a hosting cPanel.

Then, go to wp-content/plugins/ and create a new folder for your WordPress plugin. In this folder, create a PHP file through your preferred code editor. Enter this code snippet.

<?php

/**

* Plugin Name: test-plugin

* Plugin URI: https://www.your-site.com/

* Description: Test.

* Version: 0.1

* Author: your-name

* Author URI: https://www.your-site.com/

**/

Replace the placeholders with specific info about your plugin. And remember to use the .php file extension.

After this file is created, upload it to the plugin folder in wp-content/plugins/. Once uploaded, navigate to the WordPress admin dashboard and visit the ‘Plugins’ page. There, you should see your new plugin live!

Now that the basic plugin file is ready, what you need to do is bring it to life. That means implementing the functionality it’s supposed to offer to the website.

Step 2: Implement the Plugin Functionality (Using WordPress Hooks)

In this part of the process, you implement the core logic of your new plugin. For that, you need to identify the suitable action and filter hooks and integrate them in the WordPress workflow.

Action Hook

First, use the add_action function to implement (or hook) custom functions to specific actions. Let’s take an example. Here, we will add a menu item to the WordPress dashboard.

function my_new_plugin_admin_menu() {

    add_menu_page(

        'My New Plugin Settings',

        'My New Plugin',

        'manage_options',

        'my-new-plugin',

        'my_new_plugin_settings_page'

    );

}

add_action( 'admin_menu', 'my_new_plugin_admin_menu' );

function my_new_plugin_settings_page() {

    // Output your settings page content here

    echo '<h2>My New Plugin Settings</h2>';

}

Filter Hook

Next, you use the filter hook function, add_filter(), to modify the data. Here’s how you use it.

function my_new_plugin_modify_content( $content ) {

    if ( is_single() ) {

        $content .= '<p>This content was modified by My New Plugin.</p>';

    }

    return $content;

}

add_filter( 'the_content', 'my_new_plugin_modify_content' );

These hook implementations will apply the functionalities to the plugin and modify what it does, accordingly.

Step 3: Test the Plugin

Now that you have a working plugin, it’s time to test and deploy it. This is why we are using a staging or local WordPress environment. So whatever changes need to be done in the plugin won’t affect the live site.

Testing

First, check for any bugs and vulnerabilities. Use the following testing strategies:

• Debugging: Utilize WordPress debugging tools. Set WP_DEBUG to true in the wp-config.php file. Use PHP debugging techniques such as error_log() or even Xdebug to locate and fix errors.
• Compatibility Testing: Check the new plugin against different WordPress versions. Also check it with popular themes and other plugins for compatibility.
• User Testing (Optional): People other than you also need to approve of the plugin. So get someone other than you to test your plugin for feedback. See what might be wrong and which areas may have been overlooked.

After the plugin is tested and approved, you can push it to the live site. But before that, make sure to backup your WordPress website.

Deployment

Export your plugin to a zip file for easy installation. Go to your plugin folder, right-click on your particular plugin’s file and proceed to creating a zip file. This file will contain your plugin’s main directory.

(For example, Windows users will get an option to select ‘Send to’ > ‘Compressed (zipped) folder’.)

Now, go to the Plugin section on your WordPress admin dashboard and navigate to ‘Add New Plugin’. Then, you can click on ‘Choose File’, upload the compressed zip file, and click ‘Install Now’. After the installation is done, click ‘Activate’. That will activate the new plugin on your live WordPress website.

Step 4: Publish the New Plugin in WordPress Repository

There’s a chance you have created this plugin only for your own website. But by leaving some room for scalability, you may also publish it in the official WordPress repository.

But first, make sure your plugin adheres to the plugin guidelines set by WordPress. Only then can you submit the plugin for review.

Create a ‘ReadMe’ or readme.txt file for your new WordPress plugin in the dedicated plugin folder. The info you add in this file will be displayed on the official page of the plugin in the repository.

Something like this.

Here’s a sample of what you need to include in the readme.txt file. Use this as a starting point.

=== Your New Plugin Name ===

Contributors: WP Plugin Experts

Tags: wp plugin experts, plugin tutorial

Requires at least: 6.0

Tested up to: 6.2

Stable tag: 1.0

License: GPLv2 or later

License URI: http://www.gnu.org/licenses/gpl-2.0.html

Describe what your new WordPress plugin does, what the user can achieve with it. (in brief)

== Description ==

Give a description of the plugin’s functionality. 

== Installation ==

1. Upload the plugin folder to your /wp-content/plugins/ folder.

1. Go to the **Plugins** page and activate the plugin.

== Frequently Asked Questions ==

= How do I use this plugin? =

Answer to the question

= How to uninstall the plugin? =

Simply deactivate and delete the plugin. 

== Screenshots ==

1. Description of the first screenshot.

1. Description of the second screenshot. 

== Changelog ==

= 1.0 =

* Plugin released.

Make sure to review the details thoroughly as they will be displayed on your plugin’s main page in the official repository. After review, remember to save changes.

Once done, review the guidelines and add your plugin to the repository.

If you want to create an advanced plugin for your WordPress website, get our dedicated WordPress development services. We will review your technical and other requirements and develop a new WordPress plugin via a suitable approach.

Best Practices for WordPress Plugin Development

As mentioned earlier, creating a new plugin isn’t just about coding. It’s about implementing the best practices to ensure security, scalability, maintainability, and performance. All-in-all, you want to make a plugin that offers the best features but is also safe and easy to use.

Follow WordPress Coding Standards

Follow official WordPress Coding Standards for PHP, HTML, CSS, and JavaScript. These standards guarantee consistency and readability for maintaining code and easy collaboration on it.

Use WordPress Hooks Appropriately

Make full use of Action Hooks and Filter Hooks to change WordPress behavior and extend features while avoiding changing core files. This guarantees that your plugin is compatible with future updates of WordPress.

Sanitize and Validate User Input

You should always sanitize and validate any user input to prevent security vulnerabilities like cross-site scripting (XSS) and SQL injection. Use functions provided by WordPress, like sanitize_text_field(), esc_sql(), and wp_kses() for that.

Implement Nonces for Security

Make sure to use WordPress nonces to protect against CSRF attacks. Especially when you are submitting forms or performing actions which involve modifying data.

Prefix Everything Uniquely

Prefix all functions, classes, variables, constants, and database table names. Use a unique identifier related to your plugin. That prevents naming conflicts with other plugins or themes.

Enqueue Scripts and Styles Correctly

Use wp_enqueue_scripts() and admin_enqueue_scripts() to load CSS and JavaScript files for your plugin. This guarantees proper loading and that they will not run into any conflicts with other assets.

Internationalize and Localize Your Plugin

Make your plugin translation-ready by utilizing internationalization functions provided by WordPress. These are __() and _e(). Hand over a .pot file, and be ready to incorporate translation files for several languages.

Optimize Performance

Write efficient code, maintain a low query count, and put caching into perspective. That will ensure your plugin does not create a bottleneck for the website. Assets should be loaded only when needed.

Document Your Code and Provide Clear Instructions

Comments in your code must explain complex logic. Your clear, comprehensive `readme.txt` file should contain installation instructions, usage documentation, and troubleshooting advice.

If you want to make the best of these practices and create a high-quality plugin, dedicated WordPress developers will be more suitable.

FAQs on Developing a New WordPress Plugin

Final Summary

While it may seem like a complex task, developing a new WordPress plugin is relatively straightforward. It starts with creating a new plugin file. Then you add the action and filter hooks for modifying the functionalities.

After that, you test and deploy the plugin on the live website. You can even publish the plugin on the official WordPress repository and sell it (or its premium version). Depends on whether you want to address just your website or create a broader solution.

While this guide will be suitable for a basic-level plugin, if you have more advanced requirements, our WordPress development agency will be better. So, connect with us today!