Building a Domain WHOIS and Social Data WordPress Widget

Key Takeaways

• The tutorial provides a step-by-step guide to creating a WordPress widget that displays the WHOIS and social information of a domain name, including Google’s PageRank and 1 count, Alexa rank, Facebook shares and likes count, Twitter tweets, LinkedIn shares, and domain creation and expiry dates.
• The widget utilizes the JsonWhois API, which returns the required domain information in JSON format. A ‘GET’ request is sent to the endpoint with the API key and domain name as request parameters.
• The widget is coded by extending the standard WP_Widget class, including the necessary class functions or methods, and registering the widget. For each piece of domain information the widget is going to display, a method that returns the individual data is also created.
• The widget also features a back-end settings form consisting of three fields: the widget title, domain, and API key. When the form is filled, the update() method sanitizes and saves the entered values to the database for reuse. The widget() method then displays the widget on the front-end of WordPress.

In a previous tutorial, we took a deep dive into WordPress HTTP API and we learned what APIs are and how to use the HTTP API to consume web services.

I promised to show some real-world examples of how to consume APIs in WordPress using the HTTP API, this is the first in a series of upcoming articles.

In this tutorial, we will develop a WordPress widget that display the WHOIS and social information of a domain name such as Google’s PageRank and 1 count, Alexa rank, the date a domain was created, when the domain expires, DNS name servers, Facebook shares and likes count, Twitter tweets and LinkedIn shares.

The domain information listed above will be obtained from JsonWhois API.

To get this data, a GET request will be sent to the endpoint http://jsonwhois.com/api/whois with your API key and the domain name as the request parameters.

Enter the URL below into your browser to reveal available information (in JSON format) about the domain sitepoint.com:

http://jsonwhois.com/api/whois/?apiKey=54183ad8c433fac10b6f5d7c&domain=sitepoint.com

It is from the JSON object the widget we develop will get its data from.

If you want to jump ahead in this tutorial, you can view a demo of the widget and download the widget plugin.

Coding the Widget

First off, include the plugin header.

<span><span><?php
</span></span><span>
</span><span><span>/*
</span></span><span><span>Plugin Name: Domain Whois and Social Data
</span></span><span><span>Plugin URI: https://www.sitepoint.com
</span></span><span><span>Description: Display whois and social data of a Domain.
</span></span><span><span>Version: 1.0
</span></span><span><span>Author: Agbonghama Collins
</span></span><span><span>Author URI: http://w3guy.com
</span></span><span><span>License: GPL2
</span></span><span><span>*/</span></span>

To create a WordPress widget; first extend the standard WP_Widget class, include the necessary class functions or methods and finally, register the widget.

Create a child-class extending the WP_Widget class.

<span>class Domain_Whois_Social_Data extends WP_Widget {
</span><span>// ...</span>

Give the widget a name and description using the __construct() magic method as follows.

http://jsonwhois.com/api/whois/?apiKey=54183ad8c433fac10b6f5d7c&domain=sitepoint.com

We will create a method called json_whois_api that will accept two arguments: the domain to query and your API key whose duty is to send a ‘GET’ request to the JsonWhois API, retrieve the response body and then convert the response to an object using json_decode() function.

<span><span><?php
</span></span><span>
</span><span><span>/*
</span></span><span><span>Plugin Name: Domain Whois and Social Data
</span></span><span><span>Plugin URI: https://www.sitepoint.com
</span></span><span><span>Description: Display whois and social data of a Domain.
</span></span><span><span>Version: 1.0
</span></span><span><span>Author: Agbonghama Collins
</span></span><span><span>Author URI: http://w3guy.com
</span></span><span><span>License: GPL2
</span></span><span><span>*/</span></span>

For each piece of domain information the widget is going to display, a method that returns the individual data will also be created. That is, a method that returns the Alexa Rank, PageRank and so on will be created.

Worthy of Note

For those new to PHP programming and WordPress plugin development, you might find the something like this strange:

<span>class Domain_Whois_Social_Data extends WP_Widget {
</span><span>// ...</span>

The -> is used to access an object property and [] for accessing an array.

The reason for this is that the response return by JsonWhois after being decoded to an object is a multidimensional object with some property containing array as values.

The code below explains this $object->facebook->data[0]->share_count;

<span>function __construct() {
</span>		<span><span>parent::</span>__construct(
</span>			<span>'whois_social_widget', // Base ID
</span>			<span>__( 'Domain Whois and Social Data', 'dwsd' ), // Name
</span>			<span>array( 'description' => __( 'Display whois and social data of a Domain.', 'dwsd' ), ) // Description
</span>		<span>);
</span>	<span>}</span>

In no particular order, below are the class methods or functions that will return the various domain information the WordPress widget will display.

<span>/**
</span><span>	 * Retrieve the response body of the API GET request and convert it to an object
</span><span>	 * 
</span><span>	 * <span>@param $domain
</span></span><span>	 * <span>@param $api_key
</span></span><span>	 *
</span><span>	 * <span>@return <span>object|mixed</span>
</span></span><span>	 */
</span>	<span>public function json_whois_api( $domain, $api_key ) {
</span>
		<span>$url = 'http://jsonwhois.com/api/whois/?apiKey=' . $api_key . '&domain=' . $domain;
</span>
		<span>$request = wp_remote_get( $url );
</span>
		<span>$response_body = wp_remote_retrieve_body( $request );
</span>
		<span>$decode_json_to_object = json_decode( $response_body );
</span>
		<span>return $decode_json_to_object;
</span>
	<span>}</span>

<span>return $response_data->social->facebook->data[0]->share_count;</span>

<span>[facebook] => stdClass Object
</span>                <span>(
</span>                    <span>[data] => Array
</span>                        <span>(
</span>                            <span>[0] => stdClass Object
</span>                                <span>(
</span>                                    https<span>%3A%2F%2Feditor.sitepoint.com => https://www.sitepoint.com
</span>                                    <span>[normalized_url] => https://www.sitepoint.com/
</span>                                    <span>[share_count] => 1094
</span>                                    <span>[like_count] => 448
</span>                                    <span>[comment_count] => 161
</span>                                    <span>[total_count] => 1703
</span>                                    <span>[commentsbox_count] => 0
</span>                                    <span>[comments_fbid] => 501562723433
</span>                                    <span>[click_count] => 138
</span>                                <span>)
</span>
                        <span>)
</span>
                <span>)</span>

<span>/**
</span><span>	 * Get the domain Alexa Rank
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>integer</span>
</span></span><span>	 */
</span>	<span>public function alexa_rank( $response_data ) {
</span>
		<span>return $response_data->alexa->rank;
</span>
	<span>}</span>

<span>/**
</span><span>	 * Number of times domain have been tweeted
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>integer</span>
</span></span><span>	 */
</span>	<span>public function twitter_tweets( $response_data ) {
</span>
		<span>return $response_data->social->twitter->count;
</span>
	<span>}</span>

<span>/**
</span><span>	 * Number of times domain have been shared on Facebook
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>integer</span>
</span></span><span>	 */
</span>	<span>public function facebook_share_count( $response_data ) {
</span>
		<span>return $response_data->social->facebook->data[0]->share_count;
</span>
	<span>}</span>

<span>/**
</span><span>	 * Number of times domain have been liked on Facebook
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>mixed</span>
</span></span><span>	 */
</span>	<span>public function facebook_like_count( $response_data ) {
</span>
		<span>return $response_data->social->facebook->data[0]->like_count;
</span>
	<span>}</span>

<span>/**
</span><span>	 * Number of times domain have been shared to LinkedIn
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>integer</span>
</span></span><span>	 */
</span>	<span>public function linkedin_share( $response_data ) {
</span>
		<span>return $response_data->social->linkedIn;
</span>
	<span>}</span>

<span>/**
</span><span>	 * Number of times domain have been shared on Google+
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>integer</span>
</span></span><span>	 */
</span>	<span>public function google_share( $response_data ) {
</span>
		<span>return $response_data->social->google;
</span>
	<span>}</span>

<span>/**
</span><span>	 * Google PageRank of Domain
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>integer</span>
</span></span><span>	 */
</span>	<span>public function google_page_rank( $response_data ) {
</span>
		<span>return $response_data->google->rank;
</span>
	<span>}</span>

The back-end widget settings form is created by the form() method consisting of three form fields which house the widget title, domain and your API key.

<span>/**
</span><span>	 *Domain name servers
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>string</span>
</span></span><span>	 */
</span>	<span>public function domain_nameservers( $response_data ) {
</span>
		<span>$name_servers = $response_data->whois->domain->nserver;
</span>
		<span>return $name_servers->{0} . ' ' . $name_servers->{1};
</span>
	<span>}</span>

When the widget form is filled, the update() method sanitizes and saves the entered values to the database for reuse.

<span>/**
</span><span>	 * Date domain was created
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>mixed</span>
</span></span><span>	 */
</span>	<span>public function date_created( $response_data ) {
</span>
		<span>return $response_data->whois->domain->created;
</span>	<span>}</span>

The widget() method displays the widget in the front-end of WordPress.

<span>/**
</span><span>	 * Domain expiration date
</span><span>	 *
</span><span>	 * <span>@param <span>object</span> $response_data JSON decoded response body
</span></span><span>	 *
</span><span>	 * <span>@return <span>mixed</span>
</span></span><span>	 */
</span>	<span>public function expiration_date( $response_data ) {
</span>
		<span>return $response_data->whois->domain->expires;
</span>	<span>}</span>

Code explanation: First, the saved widget form values (title, domain and API key) are retrieved from the database and saved to a variable.

The domain and API key are passed to the json_whois_api method with the resultant response body saved to $api_response.

Calls to the various methods that return the domain data are made with the response body ($api_response) as an argument.

Finally, we close the widget class.

/**
	 * Back-end widget form.
	 *
	 * @see WP_Widget::form()
	 *
	 * @param array $instance Previously saved values from database.
	 *
	 * @return string
	 */
	public function form( $instance ) {
		if ( isset( $instance['title'] ) ) {
			$title = $instance['title'];
		} else {
			$title = __( 'Domain Whois & Social Data', 'dwsd' );
		}

		$domain_name = isset( $instance['domain_name'] ) ? $instance['domain_name'] : '';

		$api_key = isset( $instance['api_key'] ) ? $instance['api_key'] : '54183ad8c433fac10b6f5d7c';

		?>
		<span><span><span><p</span>></span>
</span>			<span><span><span><label</span> for<span>="<span><?php echo $this->get_field_id( 'title' ); ?></span>"</span>></span><span><?php _e( 'Title:' ); ?></span><span><span></label</span>></span>
</span>			<span><span><span><input</span> class<span>="widefat"</span> id<span>="<span><?php echo $this->get_field_id( 'title' ); ?></span>"</span>
</span></span><span>			       <span>name<span>="<span><?php echo $this->get_field_name( 'title' ); ?></span>"</span> type<span>="text"</span>
</span></span><span>			       <span>value<span>="<span><?php echo esc_attr( $title ); ?></span>"</span>></span>
</span>		<span><span><span></p</span>></span>
</span>
		<span><span><span><p</span>></span>
</span>			<span><span><span><label</span>
</span></span><span>				<span>for<span>="<span><?php echo $this->get_field_id( 'domain_name' ); ?></span>"</span>></span><span><?php _e( 'Domain name (without http://)' ); ?></span><span><span></label</span>></span>
</span>			<span><span><span><input</span> class<span>="widefat"</span> id<span>="<span><?php echo $this->get_field_id( 'domain_name' ); ?></span>"</span>
</span></span><span>			       <span>name<span>="<span><?php echo $this->get_field_name( 'domain_name' ); ?></span>"</span> type<span>="text"</span>
</span></span><span>			       <span>value<span>="<span><?php echo esc_attr( $domain_name ); ?></span>"</span>></span>
</span>		<span><span><span></p</span>></span>
</span>
		<span><span><span><p</span>></span>
</span>			<span><span><span><label</span> for<span>="<span><?php echo $this->get_field_id( 'api_key' ); ?></span>"</span>></span><span><?php _e( 'API Key)' ); ?></span><span><span></label</span>></span>
</span>			<span><span><span><input</span> class<span>="widefat"</span> id<span>="<span><?php echo $this->get_field_id( 'api_key' ); ?></span>"</span>
</span></span><span>			       <span>name<span>="<span><?php echo $this->get_field_name( 'api_key' ); ?></span>"</span> type<span>="text"</span>
</span></span><span>			       <span>value<span>="<span><?php echo esc_attr( $api_key ); ?></span>"</span>></span>
</span>		<span><span><span></p</span>></span>
</span>	<span><span><?php
</span></span><span>	<span>}</span></span>

The widget class needs to be registered by being hooked to widgets_init Action so it is recognized by WordPress internals.

<span>/**
</span><span>	 * Sanitize widget form values as they are saved.
</span><span>	 *
</span><span>	 * <span>@see WP_Widget::update()
</span></span><span>	 *
</span><span>	 * <span>@param <span>array</span> $new_instance Values just sent to be saved.
</span></span><span>	 * <span>@param <span>array</span> $old_instance Previously saved values from database.
</span></span><span>	 *
</span><span>	 * <span>@return <span>array</span> Updated safe values to be saved.
</span></span><span>	 */
</span>	<span>public function update( $new_instance, $old_instance ) {
</span>		<span>$instance                = array();
</span>		<span>$instance['title']       = ( ! empty( $new_instance['title'] ) ) ? strip_tags( $new_instance['title'] ) : '';
</span>		<span>$instance['domain_name'] = ( ! empty( $new_instance['domain_name'] ) ) ? strip_tags( $new_instance['domain_name'] ) : '';
</span>
		<span>return $instance;
</span>	<span>}</span>

Below is a screenshot of the widget.

View a demo of the widget.

Related Resources

If you’re interested in learning more about how WordPress widgets work, you might be interested in the following articles:

• WordPress Widget API
• Build a Tabbed WordPress Login and Registration Widget
• Creating Widgets in WordPress via the Widgets API
• Creating a World Cup 2014 WordPress Widget

Wrap Up

To further understand how the widget was built and how to implement it on your WordPress site, download the widget plugin from GitHub.

As I mentioned, this article is the first in a series that will demonstrate how the WordPress HTTP API is used in a plugin.

Be sure to keep an eye on the WordPress channel for similar tutorials.

Until we meet again, happy coding!

Frequently Asked Questions about Building a Domain Whois and Social Data WordPress Widget

How can I install the Domain Whois and Social Data WordPress Widget on my website?

To install the Domain Whois and Social Data WordPress Widget, you need to first download the plugin from the WordPress plugin repository. Once downloaded, you can install it by navigating to your WordPress dashboard, clicking on ‘Plugins’, then ‘Add New’, and finally ‘Upload Plugin’. You can then choose the downloaded file and click ‘Install Now’. After the plugin is installed, click ‘Activate’ to start using it.

Can I customize the appearance of the widget on my website?

Yes, you can customize the appearance of the widget to match your website’s theme. The plugin comes with a CSS file that you can modify to change the look and feel of the widget. You can change the colors, fonts, and layout to suit your preferences.

How can I use the widget to search for domain information?

Once the widget is installed and activated, you can use it to search for domain information by entering the domain name in the search box and clicking ‘Search’. The widget will then display the Whois information for the domain, including the domain’s registration status, owner information, and more.

Can I use the widget to search for social data?

Yes, the widget also allows you to search for social data. It can retrieve information from various social media platforms, including Facebook, Twitter, and LinkedIn. This can be useful for understanding the social media presence of a domain.

Is the widget compatible with all WordPress themes?

The widget is designed to be compatible with most WordPress themes. However, there may be some themes that it does not work well with due to their specific coding or design. If you encounter any issues, it’s recommended to contact the plugin developer for assistance.

Can I use the widget on multiple websites?

Yes, once you’ve downloaded the plugin, you can use it on multiple websites. However, you will need to install and activate it on each website individually.

Is the widget updated regularly?

The widget is updated regularly to ensure it remains compatible with the latest versions of WordPress and to add new features or fix any bugs. You can check for updates from your WordPress dashboard.

Does the widget support international domain names?

Yes, the widget supports international domain names. It can retrieve Whois information for domains registered in various countries and with different domain extensions.

Can I use the widget to check the availability of a domain?

Yes, you can use the widget to check the availability of a domain. If the domain is not registered, the widget will display a message indicating that the domain is available.

Is there any limit to the number of searches I can perform with the widget?

There is no set limit to the number of searches you can perform with the widget. However, excessive use may lead to temporary IP blocking by the Whois servers to prevent abuse. It’s recommended to use the widget responsibly.

The above is the detailed content of Building a Domain WHOIS and Social Data WordPress Widget. For more information, please follow other related articles on the PHP Chinese website!