Understanding Feature

Overview

Features in FlexBase are organized around CRUD operations (Create, Read, Update, Delete) with two distinct patterns: Command-based operations for data modification and Query-based operations for data retrieval.

Feature Categories

1. Command-Based Features (Data Modification)

These features use Controllers and Handlers to modify data:

Insert Features - Create New Data

• Purpose: Add new entities to the system

• Flow: Controller → Service → Command Handler → Domain Model → Database

• Example: AddOrder, CreateProduct, RegisterUser

• HTTP Method: POST

Update Features - Modify Existing Data

• Purpose: Update existing entities

• Flow: Controller → Service → Command Handler → Domain Model → Database

• Example: UpdateOrder, EditProduct, ModifyUser

• HTTP Method: PUT

Delete Features - Remove Data

• Purpose: Permanently remove entities

• Flow: Controller → Service → Command Handler → Domain Model → Database

• Example: DeleteOrder, RemoveProduct, DeactivateUser

• HTTP Method: DELETE

Soft Delete Features - Mark as Deleted

• Purpose: Mark entities as deleted without removing them

• Flow: Controller → Service → Command Handler → Domain Model → Database

• Example: SoftDeleteOrder, ArchiveProduct, DeactivateUser

• HTTP Method: PUT

2. Query-Based Features (Data Retrieval)

These features use Controllers and Query projects to retrieve data:

GetById Features - Retrieve Single Entity by ID

• Purpose: Get one specific entity by its unique identifier

• Flow: Controller → Service → Query Handler → Database → Response

• Example: GetOrderById, GetProductById, GetUserById

• HTTP Method: GET

GetSingle Features - Retrieve Single Entity by Criteria

• Purpose: Get one entity based on specific criteria

• Flow: Controller → Service → Query Handler → Database → Response

• Example: GetOrderByNumber, GetProductBySku, GetUserByEmail

• HTTP Method: GET

GetList Features - Retrieve Multiple Entities

• Purpose: Get a collection of entities

• Flow: Controller → Service → Query Handler → Database → Response

• Example: GetOrders, GetProducts, GetUsers

• HTTP Method: GET

GetPagedList Features - Retrieve Paginated Results

• Purpose: Get entities with pagination support

• Flow: Controller → Service → Query Handler → Database → Response

• Example: GetOrdersPaged, GetProductsPaged, GetUsersPaged

• HTTP Method: GET

Control Flow Comparison

Command Flow (Insert/Update/Delete/SoftDelete)

API Request → Controller → Service → Command Handler → Domain Model → Database → Event Publishing → Response

Key Characteristics:

• Modifies data in the system

• Uses Command Handlers for business logic

• Publishes events after successful operations

• Returns success/failure status

Eventual vs Non-Eventual Provision

Non-Eventual (Synchronous) Flow:

API Request → Controller → Service → Command Handler → Domain Model → Database → Response

• Immediate Response: User gets response after data is saved

• Synchronous Processing: All operations complete before response

• Use Case: Critical operations requiring immediate confirmation

• Example: Payment processing, user registration

Eventual (Asynchronous) Flow:

API Request → Controller → Service → Command Handler → Domain Model → Database → Event Publishing → Response

• Immediate Acknowledgment: User gets acknowledgment, processing continues in background

• Asynchronous Processing: Events trigger additional processing

• Use Case: Operations that can be processed later

• Example: Email notifications, report generation, data synchronization

Query Flow (GetById/GetSingle/GetList/GetPagedList)

API Request → Controller → Service → Query Handler → Database → Response

Key Characteristics:

• Reads data from the system

• Uses Query Handlers for data retrieval

• No events published (read-only operations)

• Returns data or empty results

Implementation Pattern

Command Features

• Controller: YourEntityController_Add.cs, YourEntityController_Update.cs

• Handler: AddYourEntityHandler.cs, UpdateYourEntityHandler.cs

• Message: AddYourEntityCommand.cs, UpdateYourEntityCommand.cs

• DTO: AddYourEntityDto.cs, UpdateYourEntityDto.cs

Query Features

• Controller: YourEntityController_GetById.cs, YourEntityController_GetList.cs

• Query: GetYourEntityByIdQuery.cs, GetYourEntityListQuery.cs

• DTO: GetYourEntityDto.cs, YourEntityListDto.cs

Benefits of This Approach

• Clear Separation: Commands modify data, Queries retrieve data

• Scalability: Can scale read and write operations independently

• Maintainability: Each feature has a single responsibility

• Testability: Easy to test each component in isolation

• Performance: Optimized for different operation types

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Next Steps: Learn how to implement these features in your FlexBase applications by exploring the specific feature implementation guides! 🚀