nw5/shimen-afshar/SQL-week3

2-api/server.js

@@ -0,0 +1,198 @@
+const express = require("express");
+const app = express();
+const cors = require("cors");
+const { Pool } = require("pg");
+
+app.use(cors({ origin: "*" }));
+app.use(express.json());
+
+const pool = new pool({
+    user: "postgres",
+    host: "localhost",
+    database: "cyf_ecommerce",
+    password: 1234,
+})
+
+app.get("/customers", (req, res) => {
+    pool
+        .query("SELECT * FROM customers")
+        .then((result) => res.json(result.rows))
+        .catch((error) => {
+            console.error(error);
+            res.status(500).json(error);
+        });
+});
+app.get("/products", (req, res) => {
+    let name = req.query.name;
+
+    if (name) {
+        let query = `SELECT * FROM products INNER JOIN product_availability on products.id=product_availability.prod_id INNER JOIN suppliers ON suppliers.id=product_availability.supp_id WHERE product_name LIKE '%${name}%'`;
+        pool
+            .query(query)
+            .then((result) => res.json(result.rows))
+            .catch((error) => {
+                console.error(error);
+                res.status(500).json(error);
+            });
+    } else {
+        pool
+            .query(
+                "SELECT * FROM products INNER JOIN product_availability on products.id=product_availability.prod_id INNER JOIN suppliers ON suppliers.id=product_availability.supp_id"
+            )
+            .then((result) => res.json(result.rows))
+            .catch((error) => {
+                console.error(error);
+                res.status(500).json(error);
+            });
+    }
+});
+app.get("/customers/:customerId", function (req, res) {
+    let id = parseInt(req.params.customerId);
+    pool
+        .query("SELECT * FROM customers WHERE id = $1", [id])
+        .then((result) => res.status(200).json(result.rows))
+        .catch((error) => {
+            console.error(error);
+            res.status(500).json(error);
+        });
+});
+
+// Add a new customer
+app.post("/customers", (req, res) => {
+    let name = req.body.name;
+    let address = req.body.address;
+    let city = req.body.city;
+    let country = req.body.country;
+
+    // validation
+    if (!name && !address) {
+        return res.status(400).json("Please include a name and address");
+    }
+    const query =
+        "INSERT INTO customers (name, address, city,country) VALUES ($1, $2, $3, $4)";
+    pool
+        .query(query, [name, address, city, country])
+        .then(() => res.status(200).json("customer created!"))
+        .catch((error) => {
+            console.error(error);
+            res.status(500).json(error);
+        });
+});
+// Add a new product
+app.post("/products", (req, res) => {
+    let product_name = req.body.name;
+    const query = "INSERT INTO products (product_name) VALUES ($1)";
+    pool
+        .query(query, [product_name])
+        .then(() => res.status(200).json("product created!"))
+        .catch((error) => {
+            console.error(error);
+            res.status(500).json(error);
+        });
+});
+app.post("/customers/:customerId/orders", (req, res) => {
+    const customerId = req.params.customerId;
+    const orderDate = req.body.order_date;
+    const orderRef = req.body.order_reference;
+    db.query("SELECT * FROM customers WHERE id = $1", [customerId]).then(
+        (result) => {
+            if (result.rows.length === 0) {
+                return res.status(400).send("An customer does not exist!");
+            } else {
+                const query =
+                    "INSERT INTO orders (order_date,order_reference,customer_id) VALUES ($1, $2, $3)";
+                db.query(query, [orderDate, orderRef, customerId])
+                    .then(() => res.send("orders added successfully!"))
+                    .catch((error) => {
+                        console.error(error);
+                        res.status(500).json(error);
+                    });
+            }
+        }
+    );
+});
+app.post("/availability", (req, res) => {
+    const productID = req.body.prod_id;
+    const supplierID = req.body.supp_id;
+    const newPrice = req.body.unit_price;
+    if (!Number.isInteger(newPrice) || newPrice <= 0) {
+        return res.status(400).send("The price should be a positive integer.");
+    }
+    db.query("SELECT * FROM products WHERE id=$1", [productID]).then((result) => {
+        if (result.rows.length === 0) {
+            return res.status(400).send("An product id does not exist!");
+        }
+        db.query("SELECT * FROM suppliers WHERE id=$1", [supplierID]).then(
+            (result) => {
+                if (result.rows.length === 0) {
+                    return res.status(400).send("An supplier id does not exist!");
+                }
+                db.query(
+                    "SELECT * FROM product_availability WHERE prod_id=$1 AND supp_id=$2",
+                    [productID, supplierID]
+                ).then((result) => {
+                    if (result.rows.length > 0) {
+                        return res.status(400).send("This availability already exists.");
+                    }
+                    const query =
+                        "INSERT INTO product_availability (prod_id, supp_id, unit_price) VALUES ($1, $2, $3)";
+                    db.query(query, [productID, supplierID, newPrice])
+                        .then(() => res.send("Availability created!"))
+                        .catch((error) => {
+                            console.error(error);
+                            res.status(500).send(error);
+                        });
+                });
+            }
+        );
+    });
+});
+
+app.get("/customers/:customerId/orders", (req, res) => {
+    const customerId = req.params.customerId;
+
+    const query = `SELECT o.order_reference, o.order_date, p.product_name, pa.unit_price, s.supplier_name, i.quantity
+               FROM orders o
+               INNER JOIN order_items i
+               ON o.id = i.order_id
+               INNER JOIN products p
+               ON i.product_id = p.id
+               INNER JOIN suppliers s
+               ON i.supplier_id = s.id
+               INNER JOIN product_availability pa
+               ON i.product_id = pa.prod_id AND i.supplier_id = pa.supp_id
+               WHERE o.customer_id = $1`;
+
+    db.query(query, [customerId])
+        .then((result) => res.json(result.rows))
+        .catch((error) => {
+            console.error(error);
+            res.status(500).json(error);
+        });
+});
+app.delete("/orders/:orderId", function (req, res) {
+    const orderId = req.params.orderId;
+
+    db.query("DELETE FROM orders WHERE id=$1", [orderId])
+        .then(() => res.send(`order ${orderId} deleted!`))
+        .catch((error) => {
+            console.error(error);
+            res.status(500).json(error);
+        });
+});
+
+//Delete customer
+app.delete("/customers/:customersId", function (req, res) {
+    let id = parseInt(req.params.customersId); // int = integer
+    pool
+        .query("DELETE FROM customers WHERE id=$1", [id])
+        .then(() => res.status(200).json(`customer ${id} deleted!`))
+        .catch((error) => {
+            console.error(error);
+            res.status(500).json(error);
+        });
+});
+
+app.listen(3000, function () {
+    console.log("Server is listening on port 3000. Ready to accept requests!");
+});