Angular 10 Nodejs PostgreSQL CRUD Examples with Sequelize ORM and Express Framework - Backend Nodejs development

Author: loizenai

Angular-Nodejs-PostgreSQL-CRUD-Application-Backend/app/config/db.config.js

@@ -0,0 +1,24 @@
+const env = require('./env.js');
+ 
+const Sequelize = require('sequelize');
+const sequelize = new Sequelize(env.database, env.username, env.password, {
+  host: env.host,
+  dialect: env.dialect,
+  operatorsAliases: false,
+ 
+  pool: {
+    max: env.max,
+    min: env.pool.min,
+    acquire: env.pool.acquire,
+    idle: env.pool.idle
+  }
+});
+ 
+const db = {};
+ 
+db.Sequelize = Sequelize;
+db.sequelize = sequelize;
+ 
+db.Customer = require('../models/customer.model.js')(sequelize, Sequelize);
+ 
+module.exports = db;

Angular-Nodejs-PostgreSQL-CRUD-Application-Backend/app/config/env.js

@@ -0,0 +1,15 @@
+const env = {
+  database: 'loizenaidb',
+  username: 'postgres',
+  password: '123',
+  host: 'localhost',
+  dialect: 'postgres',
+  pool: {
+    max: 5,
+    min: 0,
+    acquire: 30000,
+    idle: 10000
+  }
+};
+
+module.exports = env;

Angular-Nodejs-PostgreSQL-CRUD-Application-Backend/app/controllers/controller.js

@@ -0,0 +1,148 @@
+const db = require('../config/db.config.js');
+const Customer = db.Customer;
+
+/**
+ * Save a Customer object to database MySQL/PostgreSQL
+ * @param {*} req 
+ * @param {*} res 
+ */
+exports.create = (req, res) => {
+    let customer = {};
+
+    try{
+        // Building Customer object from upoading request's body
+        customer.firstname = req.body.firstname;
+        customer.lastname = req.body.lastname;
+        customer.address = req.body.address;
+        customer.age = req.body.age;
+    
+        // Save to MySQL database
+        Customer.create(customer).then(result => {    
+            // send uploading message to client
+            res.status(200).json({
+                message: "Upload Successfully a Customer with id = " + result.id,
+                customers: [result],
+                error: ""
+            });
+        });
+    }catch(error){
+        res.status(500).json({
+            message: "Fail!",
+            customers: [],
+            error: error.message
+        });
+    }
+}
+
+/**
+ * Retrieve Customer information from database
+ * @param {*} req 
+ * @param {*} res 
+ */
+exports.retrieveAllCustomers = (req, res) => {
+    // find all Customer information from 
+    try{
+        Customer.findAll({attributes: ['id', 'firstname', 'lastname', 'age', 'address']})
+        .then(customerInfos => {
+            res.status(200).json({
+                message: "Get all Customers' Infos Successfully!",
+                customers: customerInfos,
+                error: ""
+            });
+        })
+    }catch(error) {
+        // log on console
+        console.log(error);
+
+        res.status(500).json({
+            message: "Error!",
+            customers: [],
+            error: error
+        });
+    }
+}
+
+/**
+ * Updating a Customer
+ * @param {*} req 
+ * @param {*} res 
+ */
+exports.updateById = async (req, res) => {
+    try{
+        let customerId = req.params.id;
+        let customer = await Customer.findByPk(customerId);
+    
+        if(!customer){
+            // return a response to client
+            res.status(404).json({
+                message: "Not Found for updating a customer with id = " + customerId,
+                customers: [],
+                error: "404"
+            });
+        } else {    
+            // update new change to database
+            let updatedObject = {
+                firstname: req.body.firstname,
+                lastname: req.body.lastname,
+                address: req.body.address,
+                age: req.body.age
+            }
+            let result = await Customer.update(updatedObject, {returning: true, where: {id: customerId}});
+            
+            // return the response to client
+            if(!result) {
+                res.status(500).json({
+                    message: "Error -> Can not update a customer with id = " + req.params.id,
+                    error: "Can NOT Updated",
+                    customers: []
+                });
+            }
+
+            res.status(200).json({
+                message: "Update successfully a Customer with id = " + customerId,
+                customers: [updatedObject],
+                error: ""           
+            });
+        }
+    } catch(error){
+        res.status(500).json({
+            message: "Error -> Can not update a customer with id = " + req.params.id,
+            error: error.message,
+            customers: []
+
+        });
+    }
+}
+
+/**
+ *  Delete a Customer by ID
+ * @param {*} req 
+ * @param {*} res 
+ */
+exports.deleteById = async (req, res) => {
+    try{
+        let customerId = req.params.id;
+        let customer = await Customer.findByPk(customerId);
+
+        if(!customer){
+            res.status(404).json({
+                message: "Does Not exist a Customer with id = " + customerId,
+                error: "404",
+                customers: []
+            });
+        } else {
+            await customer.destroy();
+            res.status(200).json({
+                message: "Delete Successfully a Customer with id = " + customerId,
+                customers: [customer],
+                error: ""
+            });
+        }
+    } catch(error) {
+        res.status(500).json({
+            message: "Error -> Can NOT delete a customer with id = " + req.params.id,
+            error: error.message,
+            customers: []
+        });
+    }
+}

Angular-Nodejs-PostgreSQL-CRUD-Application-Backend/app/models/customer.model.js

@@ -0,0 +1,23 @@
+module.exports = (sequelize, Sequelize) => {
+	const Customer = sequelize.define('customer', {	
+	  id: {
+			type: Sequelize.INTEGER,
+			autoIncrement: true,
+			primaryKey: true
+    },
+	  firstname: {
+			type: Sequelize.STRING
+	  },
+	  lastname: {
+			type: Sequelize.STRING
+  	},
+	  address: {
+			type: Sequelize.STRING
+	  },
+	  age: {
+			type: Sequelize.INTEGER
+	  }
+	});
+	
+	return Customer;
+}

Angular-Nodejs-PostgreSQL-CRUD-Application-Backend/app/routers/router.js

@@ -0,0 +1,11 @@
+let express = require('express');
+let router = express.Router();
+ 
+const customers = require('../controllers/controller.js');
+
+router.post('/api/customers/create', customers.create);
+router.get('/api/customers/retrieveinfos', customers.retrieveAllCustomers);
+router.put('/api/customers/updatebyid/:id', customers.updateById);
+router.delete('/api/customers/deletebyid/:id', customers.deleteById);
+
+module.exports = router;