Attribute Macro domain_model 

#[domain_model]

Marks a struct or enum as a domain model, enforcing DDD boundaries at compile time.

This macro:

• Implements DomainModel for the type
• Validates at compile-time that fields do not use forbidden infrastructure types

Usage

// Note: This example requires `modkit` crate which is not available in proc-macro doctest context
use modkit_macros::domain_model;

#[domain_model]
pub struct User {
    pub id: i64,
    pub email: String,
    pub active: bool,
}

Compile-Time Enforcement

If any field uses an infrastructure type (e.g., http::StatusCode, sqlx::Pool), the code will fail to compile with a clear error message:

use modkit_macros::domain_model;

#[domain_model]
pub struct BadModel {
    pub status: http::StatusCode,  // ERROR: forbidden crate 'http'
}

Forbidden Types

The macro blocks types from infrastructure crates:

• Database: sqlx::*, sea_orm::*
• HTTP/Web: http::*, axum::*, hyper::*
• External clients: reqwest::*, tonic::*
• File system: std::fs::*, tokio::fs::*
• Database-specific names: PgPool, MySqlPool, SqlitePool, DatabaseConnection