I work for an Nodejs API and this is an handler file:

import express, { Request, Response } from 'express';
import { ProductStore, Product } from '../models/products';

const store = new ProductStore();

/* 
export type Product = {
    id?: number;
    name: string;
    price: number;
    category?: string;
};
*/

const index = async (_req: Request, res: Response) => {
    const products = await store.index();
    res.json(products);
};

const show = async (_req: Request, res: Response) => {
    const product = await store.show(_req.body.id);
    res.json(product);
};

const productRoutes = (app: express.Application) => {
    app.get('/products', index);
    app.get('/products/:id', show);
    app.post('/products', create);
    app.delete('/products', destroy);
};

export default productRoutes;

The respective model file is:

import client from '../database';

export type Product = {
    id?: number;
    name: string;
    price: number;
    category?: string;
};

export class ProductStore {
    async index(): Promise<Product[]> {
        try {
            // @ts-ignore
            const conn = await client.connect();
            const sql = 'SELECT * FROM products';

            const result = await conn.query(sql);

            conn.release();

            return result.rows;
        } catch (err) {
            throw new Error(`Could not GET products with error: ${err}`);
        }
    }

    async show(id: number): Promise<Product> {
        try {
            const sql = 'SELECT * FROM products WHERE id=($1)';
            // @ts-ignore
            const conn = await client.connect();

            const result = await conn.query(sql, [id]);

            conn.release();

            return result.rows[0];
        } catch (err) {
            throw new Error(`Could not find product ${id} with error: ${err}`);
        }
    }
}

When I try to index all the products, this works well, but, I can't fetch only one product for show.

The API is here in case someone want to look: https://github.com/Chaklader/StorefrontAPI

The SQL query works in the Postgres terminal. What's the issue here?