basalt-derive

Proc-macro crate for the Basalt Minecraft server. Generates Encode, Decode, and EncodedSize trait implementations for protocol packet structs and inner data types.

Macros

`#[packet(id = N)]`

Attribute macro for protocol packets. Generates all three trait impls plus a PACKET_ID constant:

#[derive(Debug, Clone, PartialEq)]
#[packet(id = 0x00)]
pub struct StatusRequest;

`#[derive(Encode, Decode, EncodedSize)]`

Standard derive macros for non-packet types (inline structs, enums, inner data structures):

#[derive(Debug, Encode, Decode, EncodedSize)]
pub struct PlayerPosition {
    pub x: f64,
    pub y: f64,
    pub z: f64,
    pub on_ground: bool,
}

Field attributes

Attribute	Effect
`#[field(varint)]`	Encode `i32` as VarInt (1-5 bytes)
`#[field(varlong)]`	Encode `i64` as VarLong (1-10 bytes)
`#[field(optional)]`	Boolean-prefixed `Option<T>`
`#[field(length = "varint")]`	VarInt length prefix for `Vec<T>`
`#[field(element = "varint")]`	Encode each element as VarInt
`#[field(rest)]`	Consume remaining bytes (last field only)

Variant attributes

#[variant(id = N)] on enum variants for discriminator-based dispatch. The discriminant is encoded as a VarInt.

License

Licensed under the Apache License, Version 2.0. See LICENSE for details.

basalt-derive 0.2.1