12. Glossary

A

Aggregate
: In Domain-Driven Design, a cluster of domain objects that can be treated as a single unit for data changes. An aggregate has one root entity through which all modifications must be made.

API Gateway
: A server that acts as an entry point for clients to access backend services. It handles tasks such as request routing, authentication, rate limiting, and load balancing.

arc42
: A template for documentation and communication of software and system architectures. It provides a consistent structure with 12 main sections covering all important aspects of architecture documentation.

Azure Container Apps (ACA)
: A managed container service from Microsoft Azure that enables deployment of containerized applications without managing underlying infrastructure.

AsyncAPI
: A specification for describing event-driven architectures and asynchronous APIs, similar to OpenAPI but for message-based communication.

B

Basket Service
: A microservice responsible for managing shopping carts and wishlists in the BookWorm e-commerce platform.

Building Block
: In architecture documentation, a component or module that encapsulates a specific functionality and can be combined with other building blocks to create larger systems.

Business Logic
: The part of a software application that encodes the real-world business rules and workflows that determine how data can be created, stored, and changed.

C

Catalog Service
: A microservice that manages the book inventory, including books, authors, categories, and related metadata in the BookWorm platform.

Chat Service
: A microservice providing real-time communication capabilities, including customer support chat and AI-powered chatbot functionality.

Circuit Breaker
: A design pattern that prevents cascading failures in distributed systems by monitoring for failures and temporarily disabling failing services.

Cloud-Native
: An approach to building and running applications that fully exploits the advantages of cloud computing, including scalability, resilience, and manageability.

Command Query Responsibility Segregation (CQRS)
: An architectural pattern that separates read and write operations into different models, optimizing each for their specific use cases.

Container
: A lightweight, portable unit that packages an application and its dependencies, enabling consistent deployment across different environments.

Correlation ID
: A unique identifier passed through all parts of a transaction or request flow, enabling tracing and debugging across distributed systems.

D

Domain-Driven Design (DDD)
: A software development approach that focuses on modeling the business domain and organizing code around business concepts rather than technical concerns.

Domain Event
: An event that represents something significant that happened in the business domain, used to communicate changes between different parts of the system.

Docker
: A platform for developing, shipping, and running applications using container technology.

E

Event Bus
: A messaging infrastructure that enables services to communicate through events in an asynchronous, decoupled manner.

Event-Driven Architecture
: An architectural pattern where components communicate through the production and consumption of events, enabling loose coupling and scalability.

Event Sourcing
: A pattern where state changes are stored as a sequence of events, providing a complete audit trail and enabling temporal queries.

Event Store
: A database optimized for storing and retrieving events in an event sourcing system.

Eventual Consistency
: A consistency model where the system will become consistent over time, often used in distributed systems to achieve better availability and partition tolerance.

G

Gemma 3
: An AI language model used in BookWorm for generating intelligent chatbot responses and natural language processing tasks.

gRPC
: A high-performance, language-agnostic remote procedure call (RPC) framework that uses HTTP/2 and Protocol Buffers.

H

Health Check
: An endpoint or mechanism that reports the operational status of a service, used for monitoring and load balancing decisions.

HybridCache
: A caching solution in .NET that combines multiple caching strategies for optimal performance and flexibility.

I

Inbox Pattern
: A messaging pattern that ensures exactly-once processing of incoming messages by storing them in a database before processing.

Infrastructure as Code (IaC)
: The practice of managing and provisioning infrastructure through machine-readable configuration files rather than manual processes.

Integration Test
: Testing that verifies the interaction between different components or services to ensure they work correctly together.

J

JWT (JSON Web Token)
: A compact, URL-safe token format used for securely transmitting information between parties as a JSON object.

K

Keycloak
: An open-source identity and access management solution that provides authentication and authorization services.

L

Load Balancer
: A component that distributes incoming requests across multiple server instances to ensure optimal resource utilization and high availability.

M

Microservices
: An architectural style where applications are built as a collection of loosely coupled, independently deployable services.

Message Broker
: A software component that enables communication between different applications or services through message passing.

MongoDB
: A document-oriented NoSQL database used in BookWorm for storing chat messages and conversations.

N

.NET Aspire
: Microsoft's cloud-native development framework that provides tools and libraries for building distributed applications.

Nomic Embed Text
: An AI service used in BookWorm for generating text embeddings to enable semantic search capabilities.

O

OAuth 2.0
: An authorization framework that enables applications to obtain limited access to user accounts on behalf of the user.

OpenAPI
: A specification for describing REST APIs, providing a standard way to document API endpoints, parameters, and responses.

OpenID Connect (OIDC)
: An identity layer built on top of OAuth 2.0 that provides authentication services.

Ordering Service
: A microservice responsible for managing the complete order lifecycle, from creation to fulfillment, in the BookWorm platform.

Outbox Pattern
: A messaging pattern that ensures reliable event publishing by storing events in the same database transaction as business data changes.

P

PostgreSQL
: An open-source relational database management system used as the primary database for most BookWorm services.

Q

Quality Attribute
: A measurable characteristic of a system that indicates how well it satisfies stakeholder needs, such as performance, security, or maintainability.

Quality Scenario
: A structured description of a quality requirement that includes stimulus, environment, artifact, response, and response measure.

R

Rating Service
: A microservice that handles book reviews, ratings, and recommendation algorithms in the BookWorm platform.

Redis
: An in-memory data structure store used for caching and session management in BookWorm.

Resilience
: The ability of a system to handle and recover from failures, continuing to provide service even when some components fail.

S

Saga Pattern
: A design pattern for managing distributed transactions across multiple services, providing consistency without requiring distributed locks.

Scalability
: The ability of a system to handle increased load by adding resources to the system, either horizontally (more instances) or vertically (more powerful instances).

SendGrid
: A cloud-based email delivery service used by BookWorm for sending notifications and communications.

Service Discovery
: A mechanism that enables services in a distributed system to find and communicate with each other without hardcoded addresses.

SignalR
: A library for adding real-time web functionality to applications, enabling server-side code to push content to clients instantly.

T

Telemetry
: The automatic collection and transmission of data from remote sources for monitoring and analysis purposes.

Technical Debt
: The cost of additional rework caused by choosing easy solutions now instead of better approaches that would take longer.

U

Ubiquitous Language
: A common language shared by domain experts and developers within a specific bounded context in Domain-Driven Design.

Unit Test
: Testing individual components or modules in isolation to verify they work correctly according to their specifications.

V

Vertical Slice Architecture
: An architectural approach that organizes code by feature rather than by technical layer, grouping all code for a feature together.

VuePress
: A static site generator optimized for creating documentation websites, used for generating BookWorm's architecture documentation.

W

WebSocket
: A communication protocol that provides full-duplex communication channels over a single TCP connection, used for real-time features.

Y

YARP (Yet Another Reverse Proxy)
: A Microsoft library for creating reverse proxy and API gateway solutions in .NET applications.

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Domain-Specific Terms

BookWorm Business Domain

Author
: A person who writes books available in the BookWorm catalog. Authors can have multiple books and biographical information.

Book
: A product in the BookWorm catalog with properties like title, description, price, category, and availability status.

Category
: A classification system for organizing books by genre, subject, or other criteria in the catalog.

Conversation
: A chat session between customers and support agents or AI chatbots in the communication system.

Customer
: A user of the BookWorm platform who can browse, purchase, and review books.

Inventory
: The available stock quantity for each book in the catalog, managed through inventory reservation and updates.

Order
: A customer's request to purchase one or more books, including shipping and payment information.

Participant
: An entity (customer, agent, or bot) that can participate in chat conversations.

Review
: Customer feedback and rating for a book, contributing to the overall book rating and recommendations.

Shopping Cart
: A temporary collection of books a customer intends to purchase, managed by the basket service.

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This glossary provides definitions for terms used throughout the BookWorm architecture documentation. It serves as a reference for developers, stakeholders, and anyone working with or studying the system.