This is not up to date (31.07.2021).
This application is a tool for digitally managing and making use of a library.
As a librarian you can add, change and remove books.
As a noramal user (reader) you can borrow and return books.
Just run npm install.
It's just NodeJs, no need to build anything!
Create a local .env file and adjust it if need be by taking a look at the supplied example.env file. Or just copy the contents and be done with it :)
Make sure that both the .json files for books and users exist and that the path is set correctly (relative to the .env file.)
If the config is setup just run npm start.
Alternatively run npm run start:dev to start the application in development mode (it just uses nodemon for auto restart on soure code changes).
This project tries to follow a clean architecture. At the top level it is split up into core and adapters, inspired by the hexagon architecture.
core contains, well, the core functionality of the app. adapters are like plug-in aspects of the app, supposed to be interchangeable. Stuff in adapters should depend on stuff in core. Through dependency injection some of the stuff in adapters goes into core though.
Within core the entities and the operations with/on them are defined, i.e. the use cases. Those are defined through various UseCase classes.
Since this is ultimately a web application, the use cases are made available through a web framework, namely express. This is implemented as an adapter. The advantage here is that the core app is not actually reliant on it being a web application, it could also be an application for the command line if another adapter is written, or something else entirely. So all the http stuff that makes a web framework is treated as nothing more than an I/O device within this project.
Same goes for the database access layer. Albeit that this aspect - namely persistant storage - is actually essential to the application. Therefore the adapter for data storage is more baked into the application and is indeed referred to in core as well. BUT, the implementation detail of how data is stored is abstracted into an adapter (here we simply use .json files instead of a database!).
A UseCase takes a request in the constructor and has an asynchronous execute() method. This runs the code required to fulfill the use case. The request contains parameters or input data guiding the use case. Data access and storage is managed in the gateways.
Beware inheritance and makeshift abstract classes!
This project uses express for all things http (plus some cool modules for making express better and easier to use like helmet), jsonwebtoken for authentication and nodemailer for sending mails. bcryptjs is used for hashing and uuid for making ids. Besides that dotenv is used for making environment dependend configuratiom just a tad more easy.
Note that in order to become a librarian or an admin you need to manually edit the users.json file and change role.