pulse-schema-derive 0.1.0-alpha.1

# pulse-schema-derive

Rust proc-macro attributes for generating [Pulse Schema Language (PSL)](https://github.com/Sansa-Organisation/pulse) from native Rust types.

## Overview

Write your schemas as standard Rust structs, enums, and traits — the proc macros emit canonical `.psl` files at compile time, giving you type-safe schema definitions verified by the Rust compiler.

## Quick Start

Add to your `Cargo.toml`:

```toml
[dependencies]
pulse-schema-derive = "0.1"
```

Define your schema:

```rust
use pulse_schema_derive::{pulse_type, pulse_enum, pulse_error, pulse_service, collection, auth};

#[pulse_type]
#[collection]
struct User {
    id: String,
    name: String,
    age: i32,
    preferences: Vec<String>,
    avatar: Vec<u8>,
    is_active: bool,
    optional_bio: Option<String>,
}

#[pulse_enum]
enum Role {
    Admin,
    Moderator,
    User,
}

#[pulse_error]
enum ProfileError {
    NotFound { id: String },
    ValidationFailed { message: String },
}

#[pulse_service]
trait UserService {
    #[auth("bearer")]
    fn create_user(name: String, age: i32) -> Result<User, ProfileError>;
}
```

Running `cargo build` generates a `schema.psl` file:

```psl
@collection
message User {
  id: string;
  name: string;
  age: int;
  preferences: string[];
  avatar: bytes;
  is_active: boolean;
  optional_bio: string?;
}

enum Role {
  Admin,
  Moderator,
  User,
}

error ProfileError {
  NotFound {
    id: string;
  },
  ValidationFailed {
    message: string;
  },
}

service UserService {
  @auth("bearer")
  rpc create_user(name: string, age: int) -> User ! ProfileError;
}
```

## Type Mappings

| Rust Type | PSL Type |
|-----------|----------|
| `String` | `string` |
| `i32`, `i64`, `u32`, `u64` | `int` |
| `f32`, `f64` | `float` |
| `bool` | `boolean` |
| `Vec<u8>` | `bytes` |
| `Vec<T>` | `T[]` |
| `Option<T>` | `T?` |
| `HashMap<K, V>` | `map<K, V>` |
| `Result<T, E>` | `-> T ! E` (in services) |

## Attributes

| Attribute | Target | PSL |
|-----------|--------|-----|
| `#[pulse_type]` | struct | `message Name { ... }` |
| `#[pulse_enum]` | enum | `enum Name { ... }` |
| `#[pulse_error]` | enum | `error Name { ... }` |
| `#[pulse_service]` | trait | `service Name { ... }` |
| `#[collection]` | struct | `@collection` |
| `#[auth("...")]` | fn | `@auth("...")` |

## Cross-Format Compatibility

This crate produces identical PSL output to the TypeScript DSL (`@pulse/schema`). Both are on-ramps to native PSL — the canonical format used for codegen, validation, and database mapping.

## License

MIT