How to return a hierarchical list of a site's page structure using the ElementAPI

Question

I'm experimenting with using Craft in a headless way and am successfully using the Element API to return all the data required to show individual pages.

However, to be able to show sub navigation and where a particular page fits into my site's 'structure' hierachy, I'd like to pull out the entire page hierarchy and then use that info in my application.

Does anyone know how to go about that using the Element API?

Thanks in advance for any clues.

Cheers,

Jim

Answer 1

It's not the most economical way to do it but if you don't have hundreds and hundreds of entries, this should do it for you:

<?php
use craft\elements\Entry;

function getChildren($entries){
    foreach ($entries as $entry) {
        $items[] = [
            'title' => $entry->title,
            'slug' => $entry->slug,
            'level' => $entry->level,
            'children' => $entry->hasDescendants ? getChildren($entry->children) : false
        ];
    }
    return $items;
}

return [
    'endpoints' => [
        'structure.json' => function() {
            return [
                'elementType' => Entry::class,
                'criteria' => [
                    'section' => 'structure',
                    'orderBy' => 'lft asc',
                    'level' => 1,
                    'limit' => null
                ],
                'transformer' => function(Entry $entry) {
                    return [
                        'title' => $entry->title,
                        'slug' => $entry->slug,
                        'level' => $entry->level,
                        'children' => $entry->hasDescendants ? getChildren($entry->children) : false
                    ];
                },
            ];
        }
    ]
];