CSCI2720代做、代写Web Applications、Java代做、代写Java编程语言

日期：2020-04-12 10:24

CSCI2720 Building Web Applications: Assignment 3

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ASSIGNMENT 3:

USING DATABASE VIA NODE.JS

RELEASED: 23 MAR 2020

DUE: 14 APR 2020 23:59

SYNOPSIS

You are going to store and manipulate some data in a database. Build a RESTful API to

serve HTTP responses for creating, retrieving, and deleting data.

BASIC SETUP

During lab 5, you have learnt to set up a basic web server using Node.js and Express. Using

either local Node.js installation or online Node.js playgrounds like Runkit.com, set up a web

server which would listen on port 3000.

In lab 6, you have further set up a MongoDB database, and access it using Mongoose in

Node.js. It is all right to use local MongoDB installation or the MongoDB Atlas Cloud.

In lab 6.5, you have set up the CSCI2720 VM account. You are recommended to try your

work for this assignment in the VM.

DATABASE SCHEMA (20%)

Schemas and models in Mongoose help to confine the types of data to be stored. These two

schemas are needed in this assignment:

Event

¨ eventId: number, required, unique

¨ name: string, required

¨ loc: ObjectId à Location documents*

¨ quota: number

Location

¨ locId: number, required, unique

¨ name: string, required

¨ quota: number

* The Event schema has been defined in lab 6, but some amendment is needed to

accommodate the reference to documents in the Locations collection.

CSCI2720 Building Web Applications: Assignment 3

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GET AND POST (30%)

Your Express server ought to respond to these requests:

¨ GET http://server address/event/event ID

When the server receives this request, it should look up the event with the given

event ID from the database. Then simply print the event name, location ID, location name,

event quota on separate lines. The location quota is not necessary. If the given event ID is not

found, output an understandable message. All the response should be sent as HTTP

responses, to be shown in the web browser. (Done in lab 6 but improvement needed)

¨ POST http://server address/event

When the server receives this request, it should use the parameters submitted in the

HTTP request body to create a new event in the database. A simple HTML form like this can

be used: http://www.cse.cuhk.edu.hk/~chuckjee/2720lab6/form.html

However, instead of letting the user decide the event ID, your code should look into the

database to find the maximum current event ID, e.g. x. Assign x+1 as the new event ID. The

form should ask the user for the location ID only but not the location name. A lookup

should be done to check if the location quota is larger than or equal to the new event quota.

If not, the event should not be created and an error message should be responded to the

user.

If the event is created successfully, respond to the user with an appropriate message (e.g.,

“Event created!”), together with the event details as in the GET response. There should be a

header field showing the URL of the created event. The HTTP status code should be 201.

DELETE (20%)

To support the RESTful API, we would allow users to delete an event using this request:

¨ DELETE http://server address/event/event ID

If the event ID is found, the event should be removed from the database. An

appropriate message is shown to the user, with the event details as in the GET response. If

the event ID is not found, show an understandable error message to the user.

CSCI2720 Building Web Applications: Assignment 3

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You may utilize the Chrome Application Postman for making DELETE requests to your

Express server during your development. Of course, you may also build user pages to send

it using JavaScript. This JS is not part of the assignment submission.

SOME MORE QUERIES (30%)

The following requests should also be entertained:

¨ GET http://server address/event

List all the events available, with details in separate lines.

¨ GET http://server address/loc

List all the locations available, with details in separate lines.

¨ GET http://server address/loc?quota=number

List all the locations with quota of at least this number. Show an appropriate

message if there is none.

¨ GET http://server address/loc/location ID

Show the details for this location ID. Show an error if the location ID is not found.

¨ GET http://server address/event/event ID/loc/location ID

List all the events which has this event ID, or which are held at this location ID.

¨ POST http://server address/loc

Create a new location with the input from a user form. Like events, decide the

location ID based on the current maximum location ID.

BONUS FEATURE

The PUT request for a complete RESTful API is still missing. Implement a convenient user

interface for updating any event and location information. The current data from the

database should be shown to the user, so that they can decide what to edit. Then update the

database with the user data, using these requests:

¨ PUT http://server address/event/event ID

¨ PUT http://server address/loc/location ID

CSCI2720 Building Web Applications: Assignment 3

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Show a message when done. You may submit an extra HTML file for this task for the form.

FEATURES AND MODULES

There is no cosmetic requirement for this assignment. You are welcome to implement extra

styles and features at your own ability. Besides Express and Mongoose, you can use any

Node.js module at your discretion, but please only use one JS file.

SUBMISSION

Before submitting, you may feel free to try with your own data in your database. We will

test your work using our database server, so you can safely clear the database server URL in

the JS file for submission.

We will only visit your web page submission using Google Chrome (almost-latest versions)

and the Chrome Application Postman. Please utilize the Developer Tools for debugging of

your code.

Please read this article carefully: http://www.cuhk.edu.hk/policy/academichonesty

Include your full name and student ID in all code files using comments. Zip all your files

and submit it on the course site on Blackboard. Only these files should be included:

¨ 1 .js file

¨ A number of HTML files, named appropriately to show their use

¨ package.json/package-lock.json from Node.js

You do not need to submit the node_modules folder.

This task is NOT a requirement of the assignment. But if you successfully do it, it

contributes to a few bonus points for your course grade:

¨ Complete fulfilment = 0.5 points

¨ Partial fulfilment = 0.25 points