added backend implementation

backend/models/usersModel.js

@@ -0,0 +1,59 @@
+import ownConn from "../dbConfig.js";
+
+//get all users
+export const getUsers = async (result) => {
+    let sql = `SELECT * FROM users ORDER BY fullName ASC`;
+    try {
+        const results = await ownConn.execute(sql)
+        result(null, results);
+    }
+    catch (err) {
+        // Manage Errors
+        console.log("SQL error : ", err);
+        result(err, null);
+    }
+};
+
+//get single user by id
+export const getUserById = async (id, result) => {
+    try {
+        let sql = `SELECT * FROM users  WHERE id = ?`;
+        const results = await ownConn.execute(sql, [id])
+        result(null, results[0]);
+    }
+    catch (err) {
+        // Manage Errors
+        console.log("SQL error : ", err);
+        result(err, null);
+    }
+};
+
+// Update user to Database
+export const updateUserById = async (data, result) => {
+    try {
+        const id = data.id;
+        let sql = `UPDATE users SET username = ?, password = ?, fullName = ?, email = ?, phonenumber = ?, address = ?, city = ?, postcode = ?, adminBool = ?, technician1Bool = ?, technician2Bool = ?, technicianMonitoringBool = ?, merchantBool = ?, internBool = ? WHERE id = ?`;
+        const results = await ownConn.query(sql, [data.username, data.password, data.fullName, data.email, data.phonenumber, data.address, data.city, data.postcode, data.adminBool, data.technician1Bool, data.technician2Bool, data.technicianMonitoringBool, data.merchantBool, data.internBool, id]);
+        result(null, results);
+    }
+    catch (err) {
+        // Manage Errors
+        console.log("SQL error : ", err);
+        result(err, null);
+    }
+};
+
+
+// Delete user to Database
+export const deleteUserById = async (id, result) => {
+    try {
+        let sql = `DELETE FROM users WHERE id = ?`;
+        const results = await ownConn.query(sql, [id])
+        result(null, results);
+    }
+    catch (err) {
+        // Manage Errors
+        console.log("SQL error : ", err);
+        result(err, null);
+    }
+};