Get WordPress Submenus in Gatsby JS - wordpress-rest-api

Question

I am fiddling around with Gatsby JS using WP as the backend and so far so good. Now I was trying to pull in the menu which for main menu items works just as expected. What I can't really wrap my head around is how to get the submenus pulled in.
The only related thing I found was https://github.com/gatsbyjs/gatsby/issues/2426 which does give me the submenus if I log the data. Just can't get them to be pulled into the menu.
Here is my query in layouts/index.js:
export const query = graphql`
query LayoutQuery {
allWordpressWpApiMenusMenusItems {
edges {
node {
name
count
items {
order
title
url
wordpress_children {
wordpress_id
title
url
}
}
}
}
}
}
`
This is my menu component:
class MainMenu extends Component {
render(){
const data = this.props.menu.allWordpressWpApiMenusMenusItems.edges["0"].node.items
console.log(data)
return(
<div>
<h1>Menu</h1>
<ul>
{data.map((item) =>
<li key={item.object_slug}>
<Link to={item.url}>
{item.title}
</Link>
</li>
)}
</ul>
</div>
)
}
}
export default MainMenu
I tried fiddling around with variations of
{item.children["0"].wordpress_children.title}
but just can't get it to work:/ Any ideas or pointers would be much appreciated!

Answer 1

I just tested this, and your logic is sound all you need is another loop to display subitems. So in your MainMenu.js you can do something like this:
class MainMenu extends Component {
render() {
const data = this.props.menu.allWordpressWpApiMenusMenusItems.edges[0].node.items
console.log(data)
return (
<div>
<h1>Main Menu</h1>
<ul>
{data.map((item) =>
<li key={item.object_slug}>
<Link to={item.url}>
{item.title}
</Link>
<ul>
{item.wordpress_children && item.wordpress_children.map((subitem) =>
<li key={item.wordpress_id}>
<Link to={subitem.url}>
{subitem.title}
</Link>
</li>
)}
</ul>
</li>
)}
</ul>
</div>
)
}
}
This line is very important {item.wordpress_children && item.wordpress_children.map((subitem)
This will check if your menu item has subitems, and if it does it will map them and iterate through them.
I hope this works for you, I tested it and it works.