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Your First CRUD API

30 minutes BEGINNER

Build your first REST API with Create, Read, Update, and Delete operations. Learn the fundamentals of GEMVC 4-layer architecture step by step.

What You'll Learn

API Service Layer

Create URL endpoints and validate requests

Controller Layer

Orchestrate business logic

Model & Table Layers

Handle data logic and database operations

Video Coming Soon...

Understanding the 4-Layer Architecture

GEMVC uses a clean 4-layer architecture pattern. Each layer has a specific responsibility, and requests flow from top to bottom:

API Layer
↓
Controller Layer
↓
Model Layer
↓
Table Layer

Follow the guides below to learn how to create each layer and build a complete CRUD API.

1

Create API Service

Layer 1: API Endpoints

The API Service Layer is the entry point for all HTTP requests. It handles URL endpoints, request validation, and authentication before delegating to the Controller layer.

Responsibilities:

  • • Define request schemas (definePostSchema(), defineGetSchema())
  • • Handle authentication ($request->auth())
  • • Validate incoming data
  • • Delegate to Controller layer
Learn to Create API Service
2

Create Controller

Layer 2: Business Logic Orchestration

The Controller Layer orchestrates business logic and coordinates between different models. It maps request data to models and handles the request/response flow.

Responsibilities:

  • • Orchestrate business logic flow
  • • Map request data to models (mapPostToObject())
  • • Coordinate multiple models if needed
  • • Handle request/response flow
  • • Delegate to Model layer
Learn to Create Controller
3

Create Model

Layer 3: Data Logic & Validations

The Model Layer contains business validations, data transformations, and error handling. It extends the Table layer and adds business logic on top of database operations.

Responsibilities:

  • • Business validations (e.g., duplicate email check)
  • • Data transformations (e.g., password hashing)
  • • Error handling and response formatting
  • • Uses Table layer methods for database operations
  • • Returns JsonResponse objects
Learn to Create Model
4

Create Table

Layer 4: Database Access & Queries

The Table Layer provides database access, query methods, and schema definition. It defines the database table structure and provides a fluent query builder interface.

Responsibilities:

  • • Define database table structure
  • • Define properties matching database columns
  • • Provide query methods (selectById(), selectByEmail())
  • • Use fluent query builder (select()->where()->limit()->run())
  • • Define schema constraints (indexes, unique keys)
Learn to Create Table

Request Flow Example

Here's how a request flows through all 4 layers:

1
API Service
POST /api/User/create → Validates schema → Calls Controller
2
Controller
Maps POST data to Model → Calls Model method
3
Model
Validates business rules → Transforms data → Calls Table
4
Table
Executes database query → Returns data → Response flows back up

🚀 Ready to Build Your First API?

Start with the API Service layer and work your way down through Controller, Model, and Table. Follow each guide to build a complete CRUD API!

Start: Create API Service Back to Learning Hub View Technical Docs