gear-mesh-derive

Procedural macro for deriving GearMesh trait on Rust types.

This crate provides the #[derive(GearMesh)] macro that automatically implements type conversion for Rust structs and enums.

Overview

The derive macro analyzes your Rust types and generates the necessary metadata for TypeScript code generation, including:

• Type structure and fields
• Generic parameters
• Documentation comments
• Validation rules
• Serde attributes

Usage

Add this to your Cargo.toml:

[dependencies]
gear-mesh = "0.1"

Then derive GearMesh on your types:

use gear_mesh::GearMesh;

#[derive(GearMesh)]
pub struct User {
    pub id: i32,
    pub name: String,
    pub email: String,
}

Attributes

Type-level Attributes

• #[gear_mesh(branded)] - Generate as a Branded Type
• #[gear_mesh(validate)] - Enable validation
• #[gear_mesh(bigint = "auto")] - Auto-detect BigInt types

Field-level Attributes

• #[validate(range(min = 0, max = 100))] - Numeric range validation
• #[validate(length(min = 1, max = 20))] - String length validation
• #[validate(email)] - Email format validation
• #[validate(url)] - URL format validation
• #[validate(pattern = "regex")] - Regex pattern validation

Example

use gear_mesh::GearMesh;

/// User ID (Branded Type)
#[derive(GearMesh)]
#[gear_mesh(branded)]
pub struct UserId(pub i32);

/// User information
#[derive(GearMesh)]
pub struct User {
    /// User's unique identifier
    pub id: UserId,
    
    /// User's display name
    #[validate(length(min = 1, max = 20))]
    pub name: String,
    
    /// User's email address
    #[validate(email)]
    pub email: String,
    
    /// User's age
    #[validate(range(min = 0, max = 150))]
    pub age: Option<i32>,
}

Implementation Details

The macro:

1. Parses the Rust type using syn
2. Extracts type information, docs, and attributes
3. Converts to GearMeshType intermediate representation
4. Serializes to JSON for runtime access
5. Implements the GearMeshExport trait
6. Registers the type with inventory for automatic collection

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE)
• MIT license (LICENSE-MIT)

at your option.