# Architecture Document
Generated: Tuesday, September 16, 2025

## System Overview
The Angular Clarity Boilerplate is a frontend-only, single-page application (SPA) template. It is designed to serve as a foundational starting point for developing enterprise-grade web applications. The system provides a pre-configured, modular, and scalable architecture using the Angular framework and is visually styled with the VMware Clarity Design System. Its primary purpose is to accelerate development by providing a structured and feature-rich starting point.

## Architecture Pattern
The boilerplate is built upon a **Component-Based Architecture**, which is fundamental to the Angular framework. The UI is composed of a tree of reusable and encapsulated components.

The overall architectural pattern follows best practices for scalable Angular applications, emphasizing a **Modular Design**. The application is segregated into a `CoreModule`, a `SharedModule`, and is designed for the addition of multiple `FeatureModules`. This structure promotes separation of concerns, reusability, and maintainability.

## Component Design (Frontend)

- **AppModule:** The root module of the application, responsible for bootstrapping the `AppComponent` and importing essential modules like the `CoreModule` and `AppRoutingModule`.

- **AppComponent:** The main application shell component. It contains the primary layout, including the Clarity header, sidebar navigation, and the main content area where routed components are displayed via `<router-outlet>`.

- **CoreModule:** This module is designed to be imported only once by the `AppModule`. It contains singleton services, route guards, and other one-time setup logic (e.g., HTTP interceptors). This pattern prevents services from being provided multiple times across the application.

- **SharedModule:** This module contains commonly used components, directives, and pipes that can be reused across different feature modules. It is imported by feature modules whenever they need access to these shared elements. It primarily exports common Angular modules (like `CommonModule`, `FormsModule`) and Clarity UI modules.

- **Feature Modules (Conceptual):** The architecture is designed for developers to create new feature modules (e.g., `DashboardModule`, `AdminModule`). These modules encapsulate all the components, services, and routing related to a specific business domain. They are typically **lazy-loaded** to improve initial application load performance.

## Data Architecture

### Primary Database
- Not applicable. As a frontend-only boilerplate, this project does not include a database. It is designed to connect to any backend with a data persistence layer.

### Data Model (Client-Side)
- Data models will be defined using **TypeScript interfaces or classes** within feature modules. These models will represent the structure of data objects retrieved from or sent to the backend API.
- **Example `User` model:**
  ```typescript
  export interface User {
    id: number;
    name: string;
    email: string;
    role: 'admin' | 'user';
  }

  Of course. Here is the architecture_document.md for the Angular Clarity boilerplate project, presented in a single code block for easy copying.

Markdown

# Architecture Document
Generated: Tuesday, September 16, 2025

## System Overview
The Angular Clarity Boilerplate is a frontend-only, single-page application (SPA) template. It is designed to serve as a foundational starting point for developing enterprise-grade web applications. The system provides a pre-configured, modular, and scalable architecture using the Angular framework and is visually styled with the VMware Clarity Design System. Its primary purpose is to accelerate development by providing a structured and feature-rich starting point.

## Architecture Pattern
The boilerplate is built upon a **Component-Based Architecture**, which is fundamental to the Angular framework. The UI is composed of a tree of reusable and encapsulated components.

The overall architectural pattern follows best practices for scalable Angular applications, emphasizing a **Modular Design**. The application is segregated into a `CoreModule`, a `SharedModule`, and is designed for the addition of multiple `FeatureModules`. This structure promotes separation of concerns, reusability, and maintainability.

## Component Design (Frontend)

- **AppModule:** The root module of the application, responsible for bootstrapping the `AppComponent` and importing essential modules like the `CoreModule` and `AppRoutingModule`.

- **AppComponent:** The main application shell component. It contains the primary layout, including the Clarity header, sidebar navigation, and the main content area where routed components are displayed via `<router-outlet>`.

- **CoreModule:** This module is designed to be imported only once by the `AppModule`. It contains singleton services, route guards, and other one-time setup logic (e.g., HTTP interceptors). This pattern prevents services from being provided multiple times across the application.

- **SharedModule:** This module contains commonly used components, directives, and pipes that can be reused across different feature modules. It is imported by feature modules whenever they need access to these shared elements. It primarily exports common Angular modules (like `CommonModule`, `FormsModule`) and Clarity UI modules.

- **Feature Modules (Conceptual):** The architecture is designed for developers to create new feature modules (e.g., `DashboardModule`, `AdminModule`). These modules encapsulate all the components, services, and routing related to a specific business domain. They are typically **lazy-loaded** to improve initial application load performance.

## Data Architecture

### Primary Database
- Not applicable. As a frontend-only boilerplate, this project does not include a database. It is designed to connect to any backend with a data persistence layer.

### Data Model (Client-Side)
- Data models will be defined using **TypeScript interfaces or classes** within feature modules. These models will represent the structure of data objects retrieved from or sent to the backend API.
- **Example `User` model:**
  ```typescript
  export interface User {
    id: number;
    name: string;
    email: string;
    role: 'admin' | 'user';
  }
Data Flow
API Call: A component's method calls a function in its corresponding service (e.g., userService.getUsers()).

Service Layer: The service uses Angular's HttpClient to make an HTTP request to the backend API.

Data Retrieval: The service receives the HTTP response and typically returns an Observable of the data, typed with the appropriate TypeScript interface.

Component Update: The component subscribes to the Observable. Once the data is received, it updates its local state, triggering Angular's change detection to re-render the template and display the new data.

API Design (Backend Communication)
This boilerplate is backend-agnostic. It is designed to communicate with any backend that exposes a RESTful or GraphQL API.

Communication Protocol
HTTP/HTTPS: Communication is handled via standard HTTP requests using Angular's HttpClient service.

Example Service Implementation
An example of a service making API calls:
// in user.service.ts
import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';
import { User } from '../models/user.model';
import { environment } from '../../environments/environment';

@Injectable({
  providedIn: 'root'
})
export class UserService {
  private apiUrl = `${environment.apiBaseUrl}/users`;

  constructor(private http: HttpClient) { }

  getUsers(): Observable<User[]> {
    return this.http.get<User[]>(this.apiUrl);
  }

  getUserById(id: number): Observable<User> {
    return this.http.get<User>(`${this.apiUrl}/${id}`);
  }
}

Error Handling
HTTP interceptors can be provided in the CoreModule to handle API errors globally (e.g., logging errors, redirecting on 401 Unauthorized responses).

Security Architecture
Authentication: Authentication logic (e.g., handling JWTs, interacting with OAuth providers) should be encapsulated within an AuthService provided in the CoreModule.

Authorization (Route Guards): The architecture uses Angular's Route Guards to protect routes. An AuthGuard can be implemented to prevent unauthorized users from accessing certain parts of the application.

Client-Side Security: The boilerplate does not inherently protect against all client-side vulnerabilities. Developers should follow best practices for preventing XSS and CSRF attacks.

Scalability Considerations
Lazy Loading: The architecture strongly encourages the use of lazy-loaded feature modules. This ensures that the initial application bundle size remains small, leading to faster load times. As new features are added, they do not impact the initial load performance.

Modular Design: The strict separation of concerns into Core, Shared, and Feature modules makes the codebase easier to manage, test, and scale as the application grows in complexity.

State Management: For applications with complex state, a state management library like NgRx or Akita can be easily integrated into this architecture without requiring significant refactoring.

---

## ARCHITECTURE UPDATE - 2025-10-09 05:02:10



# Architecture Document Update
Generated: 2025-10-09T05:00:52.000Z

## Simple Notes Taking App Feature Overview
This new feature extends the existing Angular Clarity Boilerplate to implement a "Simple Notes Taking App". The primary goal is to provide users with core functionalities for creating, viewing, editing, and deleting notes, as detailed in the `analysis_document.md` (US-001 to US-005, US-006) and `requirements_document.md` (FR-001 to FR-006). This will be achieved by integrating a new feature module into the existing application shell, adhering strictly to the boilerplate's modular architecture (FR-002 in base requirements) and the Clarity Design System (FR-003 in base requirements).

## Feature Architecture for Notes Taking App
The "Simple Notes Taking App" functionality will be encapsulated within a dedicated, lazy-loaded Angular `NotesModule`. This design choice aligns with the existing boilerplate's modular architecture (FR-002, NFR-003 in base `requirements_document.md`) and directly addresses the need for scalability and maintainability (NFR-004, NFR-006 in updated `requirements_document.md`). This module will manage its own routes, components, and services, ensuring clear separation of concerns and optimizing bundle size by loading code only when requested by the user, for example, via a new navigation item in the sidebar (FR-005 in base requirements).

## Notes Feature Module Components
Within the `NotesModule`, the following key components and services will be developed:
-   **`NotesListComponent`**: This component will be responsible for displaying a tabular or list view of all notes (FR-002 in updated `requirements_document.md`). It will leverage Clarity Data Grids (`clr-dg-row`, `clr-dg-cell`) or list components to maintain UI consistency (FR-003 in base `requirements_document.md`). It will offer navigation to individual note details (UI-003) and provide an entry point for creating new notes (UI-002).
-   **`NoteDetailComponent`**: This component will display the full title and content of a single selected note (FR-003 in updated `requirements_document.md`, UI-003). It will include actions for editing and deleting the note.
-   **`NoteFormComponent`**: A reusable component designed for both creating new notes (FR-001) and editing existing ones (FR-004). It will utilize Clarity form controls such as `clr-input` for the title and `clr-textarea` for the content, ensuring consistency with the boilerplate's UI/UX (UI-004).
-   **`NotesService`**: This injectable service will act as the primary interface for all business logic and data access operations related to `Note` entities (FR-001 to FR-006). It will abstract interactions with the backend API using Angular's `HttpClient`, promoting a clean separation between the UI and data layers (API Requirements in base `requirements_document.md`). It will manage local state for notes, possibly using RxJS `BehaviorSubject` to provide data streams to components.

## Note Data Model
The core data entity for the "Simple Notes Taking App" is the `Note`. It will be defined as a TypeScript interface to ensure strong typing and adhere to the boilerplate's data requirements for client-side entity modeling. This model directly maps to the `Note` entity described in the updated `requirements_document.md` (Data Requirements).

```typescript
interface Note {
  id: string; // Unique identifier (UUID recommended for frontend, matches backend PK)
  title: string; // Title of the note (FR-001, max 100 chars, required)
  content: string; // Body content of the note (FR-001, optional, multiline)
  createdAt: string; // ISO 8601 timestamp when the note was created (auto-generated)
  updatedAt: string; // ISO 8601 timestamp when the note was last updated (auto-updated)
  // userId?: string; // Optional: if user authentication (FR-007) is implemented
}
```

## Data Flow for Notes
1.  **Initialization/Fetching**: When `NotesListComponent` is loaded, it subscribes to the `NotesService` to fetch the list of all notes. The `NotesService` makes a GET request to `/api/notes`.
2.  **Creation**: `NoteFormComponent` (in create mode) gathers user input for `title` and `content`. Upon submission, it calls `NotesService.createNote()`, which sends a POST request to `/api/notes`. The service then updates its internal state (e.g., a `BehaviorSubject`) and notifies subscribing components.
3.  **Viewing Detail**: Clicking a note in `NotesListComponent` navigates to `NoteDetailComponent`. This component retrieves the note `id` from the route parameters and calls `NotesService.getNoteById()`, which performs a GET request to `/api/notes/{id}`.
4.  **Updating**: From `NoteDetailComponent`, an 'Edit' action leads to `NoteFormComponent` (in edit mode), pre-filled with the note's data. Upon submission, it calls `NotesService.updateNote()`, sending a PUT request to `/api/notes/{id}`. The service updates its state and notifies components.
5.  **Deletion**: From `NotesListComponent` or `NoteDetailComponent`, a 'Delete' action triggers `NotesService.deleteNote()`, sending a DELETE request to `/api/notes/{id}`. The service removes the note from its state and notifies components. All backend interactions will utilize Angular's `HttpClient` as per the boilerplate's API Requirements.

## Notes API Endpoints
The backend API will expose the following RESTful endpoints for note management, handling JSON data as per the boilerplate's API requirements and the updated `requirements_document.md` (Data Requirements):

-   **GET `/api/notes`**: Retrieves a list of all notes.
    -   **Response**: `Array<Note>` (e.g., `[ { id: '...', title: '...', content: '...', createdAt: '...', updatedAt: '...' } ]`)
-   **GET `/api/notes/{id}`**: Retrieves a single note by its unique ID.
    -   **Parameters**: `id` (path parameter, e.g., UUID)
    -   **Response**: `Note` (e.g., `{ id: '...', title: '...', content: '...', createdAt: '...', updatedAt: '...' }`)
-   **POST `/api/notes`**: Creates a new note.
    -   **Request Body**: `Omit<Note, 'id' | 'createdAt' | 'updatedAt'>` (e.g., `{ title: 'New Note', content: 'This is some content.' }`)
    -   **Response**: `Note` (the newly created note with generated `id`, `createdAt`, `updatedAt`)
-   **PUT `/api/notes/{id}`**: Updates an existing note identified by its ID.
    -   **Parameters**: `id` (path parameter)
    -   **Request Body**: `Partial<Note>` (e.g., `{ title: 'Updated Title' }` or `{ content: 'New content.' }`)
    -   **Response**: `Note` (the updated note)
-   **DELETE `/api/notes/{id}`**: Deletes a note by its unique ID.
    -   **Parameters**: `id` (path parameter)
    -   **Response**: `void` (or a status indicating success, e.g., `204 No Content`)

## Notes Feature Security Considerations
Security for the notes feature will build upon the boilerplate's foundational security practices and address specific requirements from `requirements_document.md` (NFR-005).
-   **Input Validation & Sanitization**: All user inputs (note title and content) will be validated on the frontend `NoteFormComponent` (e.g., title required, max length) and, critically, sanitized on the backend to prevent common vulnerabilities like Cross-Site Scripting (XSS) and SQL Injection (NFR-005 in updated `requirements_document.md`).
-   **HTTPS**: All communication between the Angular frontend and the backend API will be encrypted using HTTPS to protect data in transit (NFR-005).
-   **Authentication/Authorization (Future)**: If the stretch goals for user authentication (FR-007, FR-008) are implemented, then a `CoreModule` `AuthService` and `HttpInterceptors` will manage JWTs or other session tokens. The backend will enforce that users can only access/modify their own notes, preventing unauthorized access (NFR-005).

## Notes Feature Scalability
The design of the notes feature significantly contributes to the overall scalability of the application (NFR-004 in updated `requirements_document.md`).
-   **Lazy Loading**: Implementing the notes functionality within a lazy-loaded `NotesModule` ensures that the related code is only loaded when activated, keeping the initial application bundle size small and improving initial load performance (NFR-001 in base `requirements_document.md`).
-   **API-First Approach**: The frontend's reliance on a well-defined RESTful API contract allows the backend notes service to scale independently. The backend can be stateless (for notes API), utilize caching mechanisms, and be deployed across multiple instances to handle increased load without affecting the frontend architecture. (NFR-004).
-   **Data Model Extensibility**: The `Note` data model is simple yet designed for extensibility. Future features like tags, categories, or search functionality can be added by extending the `Note` interface and corresponding backend data schema, without requiring a complete rewrite of the core notes logic (NFR-004).


---

## ARCHITECTURE UPDATE - 2025-10-09 05:02:21



# Architecture Document Update - Simple Notes Taking App
Generated: 2025-10-09T05:05:00Z

## System Overview
The "Simple Notes Taking App" will be built as a **client-server application** consisting of a responsive web frontend (Single Page Application - SPA) and a RESTful API backend, supported by a persistent relational database. The core functionality revolves around CRUD (Create, Read, Update, Delete) operations for user notes. Future enhancements, such as user authentication, are considered in the design for scalability.

## Architecture Pattern
**Client-Server / N-Tier Architecture**
This pattern provides a clear separation of concerns, enabling independent development, deployment, and scaling of each component:
-   **Presentation Tier (Frontend SPA):** Handles user interface and user interaction logic. Communicates with the Application Tier via RESTful API calls.
-   **Application Tier (Backend RESTful API):** Contains the business logic, handles API requests, orchestrates data operations, and interacts with the Data Tier.
-   **Data Tier (Database):** Responsible for persistent storage and retrieval of application data.

This separation enhances maintainability, testability, and allows for horizontal scaling of the backend API.

## Component Design

### Frontend (Angular SPA)
Building upon the Angular context of the base project, the frontend will leverage a modular, component-based structure.

-   **`AppModule`**: The root module, bootstrapping the application.
-   **`CoreModule`**: (Imported once in `AppModule`) Provides singleton services (e.g., `HttpClient` for API interaction, global error handling, authentication service if implemented) and application-wide configurations.
-   **`SharedModule`**: (Imported by feature modules) Contains reusable UI components (e.g., custom buttons, modals, loaders), directives, and pipes that do not depend on singleton services.
-   **`NotesModule`**: A lazy-loaded feature module encapsulating all note-related functionality.
    -   `NoteListComponent`: Displays a list of notes with titles and content previews.
    -   `NoteDetailComponent`: Shows the full title and content of a single note.
    -   `NoteFormComponent`: Used for creating new notes and editing existing ones.
    -   `NotesService`: Handles API calls specific to notes (`GET`, `POST`, `PUT`, `DELETE`).
-   **`AuthModule` (Stretch Goal):** A lazy-loaded feature module for user registration and login.
    -   `RegisterComponent`, `LoginComponent`
    -   `AuthService`: Handles user authentication API calls.

### Backend (Python/Flask REST API)
The backend will follow a layered design for clarity and maintainability.

-   **`app.py` (Main Application Entry):** Initializes Flask app, registers blueprints.
-   **`blueprints/` (API Layer):** Organizes API endpoints (e.g., `notes_bp.py`, `auth_bp.py`).
    -   **Controllers/Routes:** Handle incoming HTTP requests, perform input validation, call appropriate services, and return JSON responses.
-   **`services/` (Service Layer):** Contains business logic for notes management and user authentication.
    -   `note_service.py`: Implements CRUD logic for notes, interacting with the repository.
    -   `auth_service.py`: (If implemented) Handles user registration, login, and password hashing.
-   **`repositories/` (Data Access Layer):** Abstracts database interactions.
    -   `note_repository.py`: Provides methods for `Note` entity persistence (e.g., `get_all`, `get_by_id`, `create`, `update`, `delete`).
    -   `user_repository.py`: (If implemented) Provides methods for `User` entity persistence.
-   **`models/` (Data Models):** Defines SQLAlchemy models for `Note` and `User` entities.
-   **`utils/`:** Common utilities like error handlers, input validators, etc.

## Data Architecture

### Primary Database: PostgreSQL (Production), SQLite (Development)
-   **Rationale:** PostgreSQL is chosen for its robustness, reliability, and advanced features suitable for production environments. SQLite offers a lightweight, file-based database ideal for local development and testing, simplifying setup.

### Entity Relationship Diagram (Conceptual)

```mermaid
erDiagram
    User {
        INTEGER id PK
        VARCHAR username UNIQUE
        VARCHAR passwordHash
        DATETIME createdAt
    }
    Note {
        INTEGER id PK
        VARCHAR title
        TEXT content
        DATETIME createdAt
        DATETIME updatedAt
        INTEGER userId FK "User ||--o{ Note"
    }
```

### Entity Details
-   **Note Entity:**
    -   `id`: Primary Key, Integer, Auto-incrementing.
    -   `title`: String (VARCHAR), max 100 characters, NOT NULL.
    -   `content`: Text (TEXT), nullable.
    -   `createdAt`: Timestamp (DATETIME), auto-generated on creation.
    -   `updatedAt`: Timestamp (DATETIME), auto-updated on modification.
    -   `userId`: Foreign Key to `User.id`, nullable initially, becomes NOT NULL if user authentication is enforced for all notes.

-   **User Entity (Optional/Stretch Goal):**
    -   `id`: Primary Key, Integer, Auto-incrementing.
    -   `username`: String (VARCHAR), unique, NOT NULL.
    -   `email`: String (VARCHAR), unique, nullable.
    -   `passwordHash`: String (VARCHAR), NOT NULL (stores securely hashed passwords).
    -   `createdAt`: Timestamp (DATETIME), auto-generated on creation.

## API Design

**API Base URL:** `/api/v1`
**Data Format:** JSON

### Notes Endpoints
-   **`GET /api/v1/notes`**
    -   **Description:** Retrieve a list of all notes.
    -   **Response:** `200 OK` with `[{ "id": ..., "title": ..., "content": ..., "createdAt": ..., "updatedAt": ... }]`

-   **`GET /api/v1/notes/{id}`**
    -   **Description:** Retrieve a single note by its ID.
    -   **Parameters:** `id` (path parameter, integer).
    -   **Response:** `200 OK` with `{ "id": ..., "title": ..., "content": ..., "createdAt": ..., "updatedAt": ... }` or `404 Not Found` if note does not exist.

-   **`POST /api/v1/notes`**
    -   **Description:** Create a new note.
    -   **Request Body:** `{ "title": "string (required)", "content": "string (optional)" }`
    -   **Response:** `201 Created` with `{ "id": ..., "title": ..., "content": ..., "createdAt": ..., "updatedAt": ... }` or `400 Bad Request` for validation errors.

-   **`PUT /api/v1/notes/{id}`**
    -   **Description:** Update an existing note by its ID.
    -   **Parameters:** `id` (path parameter, integer).
    -   **Request Body:** `{ "title": "string (required)", "content": "string (optional)" }` (fields can be partial for patch semantics, but for simplicity, full update is assumed).
    -   **Response:** `200 OK` with updated note or `404 Not Found`, `400 Bad Request`.

-   **`DELETE /api/v1/notes/{id}`**
    -   **Description:** Delete a note by its ID.
    -   **Parameters:** `id` (path parameter, integer).
    -   **Response:** `204 No Content` on success, `404 Not Found` if note does not exist.

### Authentication Endpoints (Stretch Goal)
-   **`POST /api/v1/register`**
    -   **Description:** Register a new user.
    -   **Request Body:** `{ "username": "string", "password": "string" }`
    -   **Response:** `201 Created` or `400 Bad Request` (e.g., username taken).

-   **`POST /api/v1/login`**
    -   **Description:** Authenticate a user and provide an access token.
    -   **Request Body:** `{ "username": "string", "password": "string" }`
    -   **Response:** `200 OK` with `{ "access_token": "jwt_token" }` or `401 Unauthorized`.

## Security Architecture

-   **Input Validation & Sanitization:** All user inputs (note titles, content) will be validated and sanitized on both the frontend (Angular forms) and backend (Flask/Python) to prevent common vulnerabilities like Cross-Site Scripting (XSS) and SQL injection.
-   **HTTPS Enforcement:** All communication between the frontend and backend will be secured using HTTPS to encrypt data in transit.
-   **Password Hashing (if authentication implemented):** User passwords will never be stored in plaintext. Industry-standard hashing algorithms (e.g., bcrypt) with appropriate salts will be used to store password hashes.
-   **Authentication (JWT/Session - Stretch Goal):** If user authentication is implemented, JSON Web Tokens (JWT) or secure session management will be used to verify user identity for protected resources. Tokens will be transmitted via secure headers.
-   **Error Handling:** Generic error messages will be provided to avoid leaking sensitive system information to clients.

## Scalability Considerations

-   **Stateless Backend:** The Flask API will be designed to be stateless, meaning no session data is stored on the server. This allows for easy horizontal scaling by simply adding more instances of the API server behind a load balancer.
-   **Modular Frontend:** Angular's modular structure and lazy loading capabilities ensure that only necessary code is loaded, improving initial load times and overall performance, which is crucial for perceived scalability.
-   **Database Indexing:** Appropriate indexes will be created on frequently queried columns (e.g., `id`, `userId`, `createdAt` in the `Notes` table) to optimize database read performance.
-   **Containerization (Docker):** Packaging the frontend and backend into Docker containers facilitates consistent deployment and orchestration, enabling easy scaling with tools like Kubernetes or Docker Swarm in more complex scenarios.
-   **Future Caching:** For higher read loads, a caching layer (e.g., Redis) can be introduced for frequently accessed notes or lists.
-   **Cloud-Native Deployment:** The architecture is designed to be deployed on cloud platforms, leveraging their autoscaling features for both compute and database resources.



---

## ARCHITECTURE UPDATE - 2025-10-09 05:03:06



# Architecture Document Update - Simple Notes Taking App
Generated: 2025-10-09T05:45:00Z

## Operational Considerations
To ensure the robustness and smooth operation of the Simple Notes Taking App, the following operational aspects are integrated into the architecture design:

### Monitoring & Logging
Comprehensive monitoring and logging will be implemented across both frontend and backend to provide visibility into application health, performance, and potential issues. This aligns with NFR-001 (Performance) and NFR-003 (Reliability) by ensuring operational transparency.
-   **Backend Logging:** The Flask backend will leverage Python's built-in `logging` module. Logs will include application events (e.g., API requests received, database operations), errors, and warnings. Structured logging (e.g., JSON format) will be favored for easier parsing by log aggregation tools.
-   **Frontend Error Reporting:** Angular applications will utilize a global error handler to capture unhandled JavaScript exceptions and component errors. These errors can be reported to a centralized error tracking service (e.g., Sentry, Rollbar, or a custom backend endpoint) to alert developers of client-side issues.
-   **API Monitoring:** Key API endpoints (`/api/v1/notes` CRUD operations) will be monitored for metrics such as response times, error rates (e.g., 4xx, 5xx responses), and request throughput. This helps in proactively identifying performance degradation or service outages.
-   **Infrastructure Monitoring:** If deployed to cloud providers (e.g., AWS, Azure, GCP), platform-native monitoring services (e.g., AWS CloudWatch, Azure Monitor, Google Cloud Monitoring) will be configured to track resource utilization (CPU, memory, disk I/O, network traffic) of compute instances (containers) and database services.

### Health Checks & Readiness Probes
For containerized deployments and orchestration, health check endpoints will be implemented:
-   **Backend Health Endpoint (`/healthz` or `/status`):** A simple API endpoint that returns a 200 OK status if the application is running and can connect to its dependencies (e.g., database). This is crucial for load balancers and container orchestrators (like Kubernetes) to determine if a service instance is healthy and ready to receive traffic.

## Advanced Deployment Strategy
Expanding on the `Containerization (Docker)` and `Cloud-Native Deployment` aspects, a robust deployment strategy will involve:
-   **Orchestration (Future):** For production environments, container orchestration platforms such as **Kubernetes (K8s)** or cloud-specific services like AWS Elastic Container Service (ECS) or Azure Kubernetes Service (AKS) will be employed. These platforms provide advanced features like auto-scaling, self-healing capabilities, service discovery, and declarative management of application deployments.
-   **Continuous Integration/Continuous Deployment (CI/CD):** As detailed in the technology stack, automated pipelines (e.g., GitHub Actions) will be central to the deployment process. These pipelines will automate code building, testing, Docker image creation, and deployment to staging and production environments, ensuring rapid and reliable releases.
-   **Zero-Downtime Deployments:** With orchestration tools, strategies like blue/green deployments or rolling updates will be implemented to ensure that application updates occur without any service interruption, minimizing impact on users.
-   **Environment Management:** Strict separation of configurations for development, testing, staging, and production environments will be maintained. Environment-specific variables (e.g., database connection strings, API keys) will be managed securely (e.g., Kubernetes Secrets, AWS Secrets Manager) and injected into the application containers at runtime.

