Infogram oEmbed plugin

infogram-oembed.php

<?php
/*
Plugin Name: Infogram oEmbed
Plugin URI:
Description: Adds oEmbed support for infogr.am and infogram.com urls.
Author: khromov
Version: 1.0
Author URI: https://khromov.se
*/

wp_oembed_add_provider('https://infogr.am/*', 'https://infogr.am/oembed_iframe');
wp_oembed_add_provider('https://infogram.com/*', 'https://infogram.com/oembed_iframe');

add_action('wp_footer', function() {
  ?>
  <script>
    window.addEventListener('message', function(e) {
      let data;
      try {
        data = JSON.parse(e.data);
      } catch (e) {
        return false;
      }

      if (data.context !== 'iframe.resize') {
        return false;
      }

      let iframe = document.querySelector('iframe[src="' + data.src + '"]');

      if (!iframe) {
        return false;
      }

      iframe.height = data.height;
    });
  </script>
  <?php
});