Architecture

API

• Controllers (CardController)
• Requests (input DTOs + validation)
• Responses (output DTOs)

Application

• Contract (CardResponse, CardSummary)
• Interfaces (ICardService, ICardResolver, ICardDataProvider, ICardResponseFactory, IMatrixProvider)

Domain

• Enums (EnActionFlag, EnCardType, EnCardStatus)
• Exceptions (DomainValidationException)
• Mappers (ActionFlagMapper)
• Models (CardDetails)
• Parsers (MatrixParser)
• Providers (MatrixProvider)
• Validators (MatrixValidator)

Infrastructure

• Data providers (KafkaCardDataProvider, SqlCardDataProvider, SampleCardDataProvider + DTOs)
• Mappers (CardDataMapper)
• Middleware (ApiKeyMiddleware, CorrelationIdLoggingMiddleware, IssueHandlingMiddleware)
• Services (CardService, CardResolver, CardResponseFactory)

Configuration

• API behavior (ConfigureApiBehavior)
• Logging (LoggingSetup, LogPathResolver)
• Security (KeyOption)
• Swagger (ConfigureSwaggerOptions)

Testing

• /tests — unit and integration tests (CardResolverTests, ApiKeyMiddlewareTests, etc.)

Other

• appsettings.*.json — environment config
• launchSettings.json — run/debug profiles
• Dockerfile, compose.yaml — containerization
• Program.cs — entry point