Create a JSON

wordpress-easy-post.php

<?php
/**
 * Sets up the Easy Post API Endpoints
 *
 * @package WP Theming
 */


/**
 * Sets up a JSON endpoint at /wp-json/easy-post/v1/rates/
 */
function easy_post_api_init() {

    $namespace = 'easy-post/v1';
    register_rest_route( $namespace, '/rates/', array(
        'methods' => 'GET',
        'callback' => 'easy_post_return_rates',
    ) );

}
add_action( 'rest_api_init', 'easy_post_api_init' );

/**
 * Outputs Easy Post data on the JSON endpoint
 *
 * Defaults are used if query string data is missing, but you might want to return an error instead.
 * Valid URL: /wp-json/easy-post/v1/rates/?zip=78701&width=10&length=10&height=10&weight=10&shipping_zip=78751
 */
function easy_post_return_rates( WP_REST_Request $request ) {

    // Default shipping settings
    $defaults = array(
        'zip' => 78701,
        'width' => 10,
        'length' => 10,
        'height' => 10,
        'weight' => 16,
        'shipping_zip' => 94105
    );

    // Get query strings params from request
    $params = $request->get_query_params();

    // Ensures all param keys are available
    $params = array_replace( $defaults, $params );

    // Sanitizes each of the keys
    $params = array_map( "absint", $params );

    // Creates unique key from values to set or retrieve transient
    $key = 'easy_post_' . implode( "_", $params );

    /**
     * To avoid making the same request multiple times in a short time period
     * we store the response as a transient in the WordPress database.
     *
     * This data will expire after 10 minutes.
     */
     if ( false === ( $data = get_transient( $key ) ) ) {
        $data = easy_post_make_request( $params );
        $response = new WP_REST_Response( $data );

        // Cache for 10 minutes
        set_transient( $key, $response, 60 * 10 );
    } else {
        // Returns cached value
        return get_transient( $key );
    }

    return $response;
}

/**
* Fetches data from the Easy Post API via wp_remote_post
*/
function easy_post_make_request( $params ) {

    $to_address = array(
        'zip' => $params['shipping_zip'],
        'country' => 'US'
    );

    $from_address = array(
        'zip' => $params['zip'],
        'country' => 'US'
    );

    $parcel = array(
        'length' => $params['length'],
        'width' => $params['width'],
        'height' => $params['height'],
        'weight' => $params['weight']
    );

    $request = array(
        'shipment' => array(
            'to_address' => $to_address,
            'from_address' => $from_address,
            'parcel' => $parcel
        )
    );

    $args = array(
        'method'	=> 'POST',
        'blocking'  => true,
        'headers'   => array(
            'Content-Type' => 'application/json'
        ),
        'timeout'   => 15,
        'sslverify' => false,
        'body' => json_encode( $request )
    );

    // Replace the EASYPOST_TEST_API_KEY constant with your own API Key
    $api_url = 'https://' . EASYPOST_TEST_API_KEY . ':@api.easypost.com/v2/shipments';
    $response = wp_remote_post( $api_url, $args );
    
    if ( ! is_wp_error( $response ) ) {
	$response = json_decode( $response['body'] );
    }

    return $response;
}