Assignment 15 – Simple Notes Management System (TypeScript OOP CLI)

Description

This project is a TypeScript, OOP-focused “Simple Notes Management System” implemented as an interactive command-line application. It demonstrates core object-oriented concepts (classes, inheritance, composition/aggregation/association patterns, and generics) through the app’s domain models and services.

The CLI supports:

• User signup and login
• Selecting or creating note books
• Selecting, creating, updating, and previewing notes

Features

• OOP domain models:
  • User (with age validation)
  • Admin (extends User)
  • NoteBook (stores notes)
  • Note (implements INote and provides preview())
  • Generic Storage<T> (in-memory collection)
• In-memory “database” + in-memory session state
• CLI workflow driven by @clack/prompts (select/text/password/confirm prompts)
• Note preview formatting (shows the first 50 characters of content)

Tech Stack

• TypeScript (compiled with tsc)
• Node.js with ES Modules ("type": "module", module: "nodenext")
• @clack/prompts (interactive CLI prompts)
• chalk (terminal styling)
• Node.js crypto.randomUUID() (IDs)

Folder Structure

• src/index.ts: CLI entrypoint and main interactive flow
• src/database.ts: in-memory seeded data + session getters/setters
• src/Models/
  • User.ts
  • Admin.ts
  • NoteBook.ts (also defines INote and the internal Note implementation)
  • Storage.ts
• src/Services/
  • auth.service.ts: signup/login logic
  • note.service.ts: note book/note operations
• src/util/
  • action.enms.ts: enums used by the CLI
  • types.ts: TSession type

Project diagram assets in the repo root:

• UML.jpg
• UML.drawio
• Flow Chart.drawio

Prerequisites

• Node.js and npm

Installation

npm install

Environment Variables

• None (the codebase does not use process.env or .env).

How to Run / How to Try

Run (recommended)

1. Build:

   npm run build

2. Start the CLI:

   npm run start:js

Dev (watch mode)

npm run dev

This runs the TypeScript compiler in watch mode and re-runs Node on the compiled dist/index.js.

start:ts note

npm run start:ts currently runs npx -w tsc (TypeScript compilation only) and does not start the CLI process.

Usage Overview (CLI)

When you start the app, you will see:

1. Signup / Login / Exit
2. After login, you manage note books and notes:
   • Select a note book (or choose Create new NoteBook)
   • Select a note (or choose Create new Note)
   • Choose an action:
     • Update Note (enter title and/or content)
     • Preview Note (prints a formatted preview)
     • Exit

Validation / Business Rules (from code)

• User.age must be between 18 and 60 (inclusive). Invalid values throw an error.
• Signup:
  • Prevents duplicate emails
  • Creates a new user
  • Automatically creates a notebook named main for the new user
• Login:
  • Requires matching email and password
• Note preview:
  • Displays content truncated to the first 50 characters, followed by " ..."

Seed Data (already in the in-memory “database”)

On startup, src/database.ts seeds:

• Admin user:
  • omar@admin.com / admin
• Regular users:
  • ahmed@example.com / 123456
  • sara@example.com / abcdef
• Note books:
  • For ahmed@example.com: Work Notes, Personal Notes
  • For sara@example.com: Ideas
• Notes are also pre-created under those notebooks.

Because everything is in-memory, any changes you make exist only for the current run.

Scripts

From package.json:

• build: npx tsc
• start:js: node ./dist/index.js
• start:ts: npx -w tsc
• dev: concurrently "tsc -w" "node --watch ./dist/index.js" --kill-others

Notes / Architecture Details

• In-memory data layer: src/database.ts uses Storage<T> to store users and tracks the current session (user, noteBook, note) for the CLI.
• Services layer:
  • AuthService handles signup/login and session initialization
  • NoteService handles selecting/creating note books, creating/updating notes, and generating previews
• Domain models:
  • NoteBook owns its notes internally (_notes)
  • Note references its author (User) and noteBook for association-style modeling

License

• This project is for education purposes only.