WordPress REST API

cached-posts.php

public function get_remote_posts() {
	$posts = get_transient( 'remote_posts' );
	if( empty( $posts ) ) {
		$response = wp_remote_get( 'http://mysite.com/wp-json/wp/v2/posts/' );
		if( is_wp_error( $response ) ) {
			return array();
		}

		$posts = json_decode( wp_remote_retrieve_body( $response ) );

		if( empty( $posts ) ) {
			return array();
		}

		set_transient( 'remote_posts', $posts, HOUR_IN_SECONDS );
	}

	return $posts;
}


public function widget( $args, $instance ) {
	$posts = $this->get_remote_posts();

	if( empty( $posts ) ) {
		return;
	}
	
    echo $args['before_widget'];

	if( !empty( $instance['title'] ) ) {
		echo $args['before_title'] . apply_filters( 'widget_title', $instance['title'], $instance, $this->id_base ) . $args['after_title'];
	}

	echo '<ul>';
	foreach( $posts as $post ) {
		echo '<li><a href="' . $post->link. '">' . $post->title->rendered . '</a></li>';
	}
	echo '</ul>';

	echo $args['after_widget'];

}

delete-post.php

$headers = array (
	'Authorization' => 'Basic ' . base64_encode( 'mrawesome:awesomepass' ),
);

$response = wp_remote_request( 'http://mysite.com/wp-json/wp/v2/posts/1183/', array(
	'method' => 'DELETE',
	'headers' => $headers
));

get-posts.php

$response = wp_remote_get( 'http://mysite.com/wp-json/wp/v2/posts/' );

plugin-boilerplate.php

/**
 * Plugin Name: REST API Test Widget
 * Plugin URI: http://danielpataki.com
 * Description: This plugin adds a widget that pulls posts through the REST API
 * Version: 1.0.0
 * Author: Daniel Pataki
 * Author URI: http://danielpataki.com
 * License: GPL2
 */

class My_Author_List_Widget extends WP_Widget {

	public function __construct() {
		$widget_details = array(
			'classname' => 'rest-api-test-widget',
			'description' => 'A REST API test widget that pulls posts from a different website'
		);

		parent::__construct( 'rest-api-test-widget', 'REST API Test Widget', $widget_details );

	}

	public function form( $instance ) {
        $title = ( !empty( $instance['title'] ) ) ? $instance['title'] : '';
        ?>

        <p>
            <label for="<?php echo $this->get_field_name( 'title' ); ?>">Title: </label>
            <input class="widefat" id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_name( 'title' ); ?>" type="text" value="<?php echo esc_attr( $title ); ?>" />
        </p>

        <?php
	}


	public function widget( $args, $instance ) {
        echo $args['before_widget'];

    	if( !empty( $instance['title'] ) ) {
    		echo $args['before_title'] . apply_filters( 'widget_title', $instance['title'], $instance, $this->id_base ) . $args['after_title'];
    	}

    	// Main Widget Code Here

    	echo $args['after_widget'];

	}

}

add_action( 'widgets_init', function(){
     register_widget( 'My_Author_List_Widget' );
});

show-posts.php

public function widget( $args, $instance ) {
	$response = wp_remote_get( 'http://mysite.com/wp-json/wp/v2/posts/' );

	if( is_wp_error( $response ) ) {
		return;
	}

	$posts = json_decode( wp_remote_retrieve_body( $response ) );

	if( empty( $posts ) ) {
		return;
	}
	
    echo $args['before_widget'];

	if( !empty( $instance['title'] ) ) {
		echo $args['before_title'] . apply_filters( 'widget_title', $instance['title'], $instance, $this->id_base ) . $args['after_title'];
	}


	if( !empty( $posts ) ) {
		echo '<ul>';
		foreach( $posts as $post ) {
			echo '<li><a href="' . $post->link. '">' . $post->title->rendered . '</a></li>';
		}
		echo '</ul>';
	}

	echo $args['after_widget'];

}

Nice useful post.