more detail into models and services

models/ProductModel.js

@@ -1,9 +1,26 @@
-module.exports = class ProductModel {
-    async find() {
+const db = require('../db/Pool');
 
+module.exports = class ProductModel {
+    async selectAll() {
+        try {
+            const q = "SELECT * FROM product;";
+            const result = await db.query(q);
+            if (result.rows.length) return result.rows;
+            return [];
+        } catch(e) {
+            throw new Error(e);
+        }
     }
 
     async findOne(productid) {
-
+        try {
+            const q = `SELECT * FROM product WHERE id = $1;`;
+            const filter = [productid];
+            const result = await db.query(q, filter);
+            if (result.rows.length) return result.rows[0];
+            return null;
+        } catch(e) {
+            throw new Error(e);
+        }
     }
 }