rusmes-proto

Core protocol types for the RusMES mail server. This crate defines the foundational data types used across all other RusMES crates. It has no I/O dependencies and is designed to be lightweight.

Modules

Key Types

Mail

The central mail envelope wrapping a message with routing metadata:

• Envelope sender/recipients (separate from message headers)
• Processing state (Root, Transport, LocalDelivery, Error, Ghost, Custom)
• Attributes map for inter-mailet communication
• Remote client information (IP, hostname)
• split() method for partial-recipient processing

MailAddress

Type-safe email address with validation:

• Local part (1-64 chars, no @)
• Domain (1-255 chars, lowercase normalized)
• FromStr implementation for parsing "user@example.com"

MimeMessage

Message representation with streaming support:

• MessageBody::Small(Bytes) for messages <1MB
• MessageBody::Large(...) placeholder for streaming large messages
• HeaderMap for message headers

Dependencies

• serde - serialization
• uuid - unique IDs
• bytes - efficient byte buffers
• thiserror - error types

Usage

use rusmes_proto::{Mail, MailAddress, MimeMessage, MessageBody, HeaderMap, MailState};
use bytes::Bytes;

let sender: MailAddress = "sender@example.com".parse().unwrap();
let recipient: MailAddress = "recipient@example.com".parse().unwrap();
let message = MimeMessage::new(
    HeaderMap::new(),
    MessageBody::Small(Bytes::from("Hello, World!")),
);

let mail = Mail::new(Some(sender), vec![recipient], message, None, None);
assert_eq!(mail.state, MailState::Root);

Tests

cargo test -p rusmes-proto   # 10 tests