Theme agnostic dynamic drop down menu for Wordpress

wordpress_dynamic_dropdown_menu.js

//
//	Copyright Alex DeLorenzo 2017
//
//  Dynamic Drop Down Menu for Wordpress
//		Theme agnostic.
//
//		Usage:
//
//		1) Embed this script in your page.
//
//		2) Wrap name of a menu entry with:
//
//			<div class="dd_menu" id="category_name">
//				Your Menu Entry Name Goes Here
//			</div>
		  
//		  Where `category_name` is a category used to tag articles with
//
//		3) A dynamic menu will now appear under your menu item. It will
//		   adopt your Wordpress theme's appearance and behavior
//		  

const BASE_URL = "https://organicallergyrelief.com"
const CATEGORY_ENDPOINT = "/wp-json/wp/v2/categories"
const CATEGORY_SEARCH_URL = BASE_URL + CATEGORY_ENDPOINT + '?search='


function get_menus() {
	return $(".dd_menu");
}

async function get_posts_url_for_category(category) {
	const url = CATEGORY_SEARCH_URL + category;
	const response = await fetch(url);
	const json = await response.json();
	// console.log(category)
	// console.log(json)
	// console.log(url)

	return json[0]['_links']['wp:post_type'][0]['href']
}

async function get_posts_for_category(category) {
	const post_url = await get_posts_url_for_category(category);
	const posts_response = await fetch(post_url);
	const posts_json = await posts_response.json();

	return posts_json;
} 

function get_post_titles(posts_json) {
	return posts_json.map(post_json => post_json['title']['rendered'])
}

function get_post_urls(posts_json) {
	return posts_json.map(post_json => post_json['link'])
}

function get_menu_html(titles, urls) {
	const html = ['<ul class="sub-menu dd_submenu">'];

	for (let i = 0; i < titles.length; i++) {
		html.push(`<li id="menu-item-${i}" class="menu-item menu-item-type-post_type menu-item-object-post menu-item-${i}">
						<a href="${urls[i]}">${titles[i]}</a>
				   </li>`)
	}

	html.push("</ul>")

	return html.join('\n')
}

function get_html_from_json(posts_json) {
	const titles = get_post_titles(posts_json)
	const urls = get_post_urls(posts_json)

	return get_menu_html(titles, urls)
}

async function attach_menu(menu) {
	const category = menu.id;
	const posts_json = await get_posts_for_category(category);
	const html = $(get_html_from_json(posts_json));

	const parent_li = $(menu).parent().parent();
	//parent_li.find("ul").remove();
	parent_li.append(html);
}

async function attach_menus() {
	const menus = get_menus().toArray();

	return Promise.all(menus.map(attach_menu))
}

document.addEventListener('DOMContentLoaded', attach_menus, false);