app.js

// import express
const express = require('express');

//import nedb
const Datastore = require('nedb');

// import body-parser
const bodyParser= require('body-parser');

// set up the app
const app = express();

// set up a new database
const db = new Datastore();

// logging constant
const log = (message) => console.log(message);

// add body-parsing functionality to the app
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({
    extended: true
}));

// get app to serve static files from the public directory
app.use(express.static(__dirname + '/public'));

// global variable for id
let id = 1;

// Function to build an item
// takes in a name, description and price
let itemBuilder = (itemName, itemDescription, itemPrice, itemID) => {
    // uses literal notation to create an item object
    let item = {
        name : itemName,
        description : itemDescription,
        price : itemPrice,
        _id : itemID
    }
    // returns that item object
    return item;
}

// CREATE (Post)
app.post('/create', (req,res) => {
    // log that we are running the create operation
    log(`\nCreate - POST`);
    // create an item from the request body
    let item = itemBuilder(req.body.name, req.body.description, req.body.price, parseInt(id));
    // increment our id by one
    id++;

    // insert the item into our Database
    db.insert(item, (err, item) => {
        //if there is an error, send back the error
        if (err) res.send(err);
        // otherwise 201 - Created and the item
        res.status(201).send(item);
        //log that item to console
        log(`Created item: ${JSON.stringify(item)}`);
    });
});

// READ ALL (Get)
app.get('/read', (req,res) => {
    // log that we are running the read operation
    log(`\nRead - GET`);

    // reading all items from database
    db.find({}, (err, items) => {
        //if there is an error, send back the error
        if (err) res.send(err);
        // otherwise 200 - OK
        res.status(200).send(items);
        //log the items to console
        log(`Reading items: ${JSON.stringify(items)}`);
    });
});

// READ ONE (Get)
app.get('/read/:id', (req,res) => {
    // log that we are running the read operation
    log(`\nRead - GET`);

    // reading item from database by id
    db.find({_id : parseInt(req.params.id)}, (err, item) => {
        //if there is an error, send back the error
        if (err) res.send(err);
        // otherwise 200 - OK
        res.status(200).send(item);
        //log the item to console
        log(`Reading item: ${JSON.stringify(item)}`);
    });
});

// UPDATE (Put)
app.put('/update/:id', (req,res) => {
    // log that we are running the read operation
    log(`\nUpdate - PUT`);
    // create a new item object
    let updatedItem = itemBuilder(req.body.name, req.body.description, req.body.price, parseInt(req.params.id));

    // find data in database BY using the id
    // send the new item
    db.update({_id : parseInt(req.params.id)}, updatedItem, (err, itemID) => {
        //if there is an error, send back the error
        if (err) res.send(err);
        // otherwise 200 - OK
        res.sendStatus(200);
        // log the item ID being returned
        log(`Updated item id: ${JSON.stringify(itemID)}`);
    });
});

// DELETE (Delete)
app.delete('/delete/:id', (req,res) => {
    // log that we are running the delete operation
    log(`\nDelete - DELETE`);

    // deleting item from database by id
    db.remove({_id : parseInt(req.params.id)}, (err, itemID) => {
        //if there is an error, send back the error
        if (err) res.send(err);
        // otherwise 200 - OK
        res.sendStatus(200);
        //log the item id to console
        log(`Deleted item id: ${JSON.stringify(itemID)}`);
    });
});

// export the app and the itemBuilder
module.exports = {app, itemBuilder};