example/

README

CRUDP Integration Guide

Overview

This guide explains how to integrate CRUDP into a Go project for isomorphic execution between server and WASM client. CRUDP automatically routes packets to handlers; business modules remain decoupled.

Project Structure

The example project follows this structure:

example/
├── modules/
│   ├── modules.go    # Handler instances collection & DI
│   └── users/
│       ├── user.go   # Shared: model + handler struct
│       ├── back.go   # Backend: server-side CRUD logic
│       └── front.go  # Frontend: WASM DOM updates
└── web/
    ├── client.go     # WASM entry point (Init CRUDP)
    └── server.go     # Server entry point (Init CRUDP)

Implementation Steps

1. Define Shared Entity

In CRUDP, your data model (Entity) is also your handler. This simplifies the design and ensures consistency.

• File: modules/user/user.go

All CRUD entities must implement:

• HandlerName() string: Unique name for registration.
• ValidateData(action byte, data ...any) error: Data validation logic.
• AllowedRoles(action byte) []byte: Access control (see ACCESS_CONTROL.md).

func (u *User) AllowedRoles(action byte) []byte {
    if action == 'r' { return []byte{'*'} } // Read: any authenticated user
    return []byte{'a'} // Write: only admins
}

2. Implement Backend Logic

Server-side CRUD operations receive *context.Context, *http.Request, and typed data.

• File: modules/user/back.go

Implement Create, Read, Update, or Delete methods as needed using build tags //go:build !wasm.

3. Implement Frontend Logic

WASM handlers update local state and DOM when receiving server responses.

• File: modules/user/front.go

Implement the same CRUD methods using build tags //go:build wasm.

4. Collect Modules

Each module exposes an Add() function returning its entities. Collect them in a central place.

• File: modules/modules.go

5. Server Entry Point

Initialize CRUDP, configure access control, and register routes.

• File: web/server.go

func main() {
    cp := crudp.New()
    cp.SetUserRoles(func(data ...any) []byte {
        return []byte{'*'} // Implement your role extraction logic
    })
    cp.RegisterHandlers(modules.Init()...)
    cp.RegisterRoutes(mux)
}

6. Client Entry Point

Initialize CRUDP and connect it to the global fetch handler.

• File: web/client.go

func main() {
    cp := crudp.New()
    cp.RegisterHandlers(modules.Init()...)
    cp.InitClient() // Intercepts fetch responses
    select {} // Keep WASM alive
}

Key Principles

• 📦 Decoupling: Business modules don't import CRUDP.
• 🔄 Isomorphic: Same handler struct, different logic per platform using build tags.
• ⚡ Automatic Routing: RESTful endpoints generated from handler names.
• 🛠️ Direct Initialization: No complex boilerplates; just New() + RegisterHandlers().