my-links/app/controllers/shared_collections_controller.ts

import { Visibility } from '#enums/visibility';
import Collection from '#models/collection';
import { getSharedCollectionValidator } from '#validators/shared_collection';
import type { HttpContext } from '@adonisjs/core/http';

export default class SharedCollectionsController {
	async index({ request, inertia }: HttpContext) {
		const { params } = await request.validateUsing(
			getSharedCollectionValidator
		);

		const collection = await this.getSharedCollectionById(params.id);
		return inertia.render('shared', { collection });
	}

	private async getSharedCollectionById(id: Collection['id']) {
		return await Collection.query()
			.where('id', id)
			.andWhere('visibility', Visibility.PUBLIC)
			.preload('links')
			.preload('author')
			.firstOrFail();
	}
}