Exercises | Backend Development | Book Library Application

Introduction

We have a loot of books at home and we need to create an application to manage the books, categorize them, track when and who we lend a book to, and how many copies of a certain book we own. We need to be able to update our library when we buy a new book, modify the information of an existing book and also be able to remove a book that was lost.

We need, therefore, to be able to make the following requests to our backend applications.

GET http://localhost/books

This request to the web server should return the list of books in our library. The result can be something like the following:

[
    {
        "title": "The Art Of War",
        "author": "Sun Tzu",
        "publisher": "Magoria Books",
        "dimensions": {
            "width": 12.7,
            "height": 20.32,
            "depth": 0.41,
        },
        "boughtOn": "01.07.2017"
        "lended": true,
        "isbn10": "0981162630",
        "isbn13": "978-0981162638",
        "pages": 57,
        "language": "English"
        "to": {
            "name": "person name",
            "address": "",
            "phoneNumber": "+43 ...."
        }
    }, 
    {
        "title": "Il principe",
        "author": "Nicolò Machiavelli",
        "publisher": "BUR Biblioteca Univ. Rizzoli",
        "dimensions": {
            "width": 13,
            "height": 19.8,
            "depth": 2.2,
        },
        "boughtOn": "01.10.2015"
        "lended": false,
        "isbn10": "881706694X",
        "isbn13": "978-8817066945",
        "pages": 211,
        "language": "Italian"
    }
]

Requirements

Fork this repo
Clone the forked repo.

Submission

Upon completion, run the following commands:

$ git add .
$ git commit -m "done"
$ git push origin master

Create Pull Request so your teachers can check up your work.

Instructions

Iteration #1: Create the request handler that responds to `GET http://localhost:5000`

First response of the list will be empty.

Iteration #2: Make your handler respond to `GET http://localhost:5000/books`

Notice the path /books at the end of the url.

Keep in mind the following:

https://  api.themoviedb.org  /3/search/movie  ?query=avengers&utm=something&year=2020
  |               |                  |                           |
protocol      domain name           path                query string parameters

Iteration #3: Let's create a book

Add a function that handles the request POST http://localhost:5000/books with the following data in the request.

The function should add the book to the books list.

{
    "title": "The Art Of War",
    "author": "Sun Tzu",
    "publisher": "Magoria Books",
    "dimensions": {
        "width": 12.7,
        "height": 20.32,
        "depth": 0.41,
    },
    "boughtOn": "01.07."
    "isbn10": "0981162630",
    "isbn13": "978-0981162638",
    "pages": 57,
    "language": "English"
}

After this was implemented, check that the previous request will return the inserted book. (Instruction 1)

Iteration #4: Filter books

Extend the backend (enpoint build at instruction 1) with some filtering options. The following query string parameters should be handled:

name	description	example
`author`	Filter books by author name. The search should be done with a `contains` strategy. If the Book's author contains the word given in the parameter, the book will have to be in the resulting list.	`http://localhost:5000/?author=Sun` or `http://localhost:5000/?author=Tzu`
`title`	Filter books by title using a `contains` strategy as for the author.	`http://localhost:5000/?title=Art` this will result in the book "The Art of War" to be returned.
`language`	Filter books by language using an exact equality strategy. The languagy property of the book should exactly match the given language string. The comparison though should be case insensitive.	`http://localhost:5000/?language=italian` will return the book "Il Principe" while `http://localhost:5000/?language=it` will result in an empty list.
`lended`	Filter for the books that are lended or books that are not lended. Dipending on the given value for this filter.	`http://localhost:5000/?lended=true` will return "The Art of War"

The filter functions for the books list should work as a chain. The resulting books list should have considered all the given lists.

Therefore the following request to the backend application

http://localhost:5000/?author=Sun&title=War&lended=true&language=english will return a list of 1 element, the book "The Art of War".

Iteration #5: Test your backend application's endpoints

Use curl or Postman to send the GET requests and POST requests to your backend application. Search online how to make a POST request and send the book object to your backend.

e.g. using curl

curl -XGET http://localhost:5000/books

curl -XPOST http://localhost:5000/books -d "{....}"

Iteration #6: Cover your functions with test cases using jest.

Code refactoring

Improve the readability of your code by splitting up the functions in smaller functions.
Cover your functions with unit tests using jest. Create the test cases and run them with jest to veryfy that the code is working as expected.

Iteration #7: Obtain one single book, given it's isbn10 code

Code refactoring

Improve the readability of your code by splitting up the functions in smaller functions.
Cover your functions with unit tests using jest. Create some exceptions

Iteration #8: Bonus | Persistence layer

Make your books library be persistent and independent from the state of your backend applications - i.e. Running / Stopped.

Until this point, everytime you restart your node application, your books list is reset. Find a way to make your books be stored on a persistent layer.

Search online for a way to do that autonomously.

Happy coding! ❤️

Thekolorz/book-backend