API.js

const express = require('express');
const router = express.Router();

//TODO: put models into own package
class IdentifiableModel {

    //TODO: proptypes or typescript
    constructor(id) {
        this.id = id;
    }

}

class Category extends IdentifiableModel {

    //TODO: prop types or typescript
    constructor(id, name, description, products) {
        super(id);
        this.name = name;
        this.description = description;
        this.products = products;
    }

}

const store = {
    categories: [
        new Category('663864f8-3e46-4192-b4cf-55f2918da53d', 'Shoes', 'See all available shoes.', []),
        new Category('098233c7-c8b3-4b96-956c-8c6d538f8824', 'Pants', 'See all available pants.', []),
        new Category('98c672b3-c30c-484c-8008-ff4a41055158', 'Dresses', 'See all available dresses.', []),
        new Category('faee1ec0-ca29-49c0-a629-d1b8586d3761', 'Skirts', 'See all available skirts.', []),
        new Category('42e04604-f3e7-4f71-9d58-1f6cfc153551', 'Shirts', 'See all available shirts.', []),
        new Category('37fd652b-509d-4430-b730-974f308ccbe8', 'Socks', 'See all available socks.', []),
        new Category('2a6d93c4-d920-4d3e-aaf5-4c42da992703', 'Suits', 'See all available suits.', []),
    ]
};

//return all categories
router.get('/categories', (req, res) => {
    res.json({ categories: store.categories });
});

//return single category where category[:filter] === :value
router.get('/categories/:filter/:value', (req, res) => {
    const category = store.categories.find(c => c[req.params.filter] === req.params.value);
    res.json({ category: category || {} });
});

module.exports = router;