Crate offline_protocol_transport 

Transport abstraction layer for the Offline Protocol SDK.

This crate defines the Transport trait and the transport state machines for BLE, the peer stream (the wifi_direct slot), Internet, Nostr, and Reticulum, plus the one Rust implementation of the peer-stream framing (stream_framing).

This crate performs no network or radio I/O

No sockets are opened and no radios are touched here. Each transport is a thread-safe protocol/queue engine — status, send/receive queues, metrics, and (for BLE) fragmentation state — driven from two sides:

• The protocol engine talks to the Transport trait: send() enqueues an outbound message, receive() dequeues an inbound one.
• A platform bridge (Swift/Kotlin via the UniFFI bindings, or any host program) owns the actual sockets, relays, and radios. It drains the outbound queue (get_next_message() / get_next_signed_event() / get_next_fragment()), performs the real I/O, reports the outcome (confirm_sent() / report_send_failure()), injects inbound bytes (on_data_received() / on_fragment_received()), and drives availability (on_status_changed()).

Without a platform bridge attached, send() queues messages that never go anywhere — and, BLE excepted, start() never makes a transport Available in the first place, so send() returns TransportNotAvailable. A pure-Rust consumer must play the bridge role itself: mark the transport available, drain the queues, and do its own I/O.

Most transports signal pending outbound work through a set_on_messages_available callback instead of requiring a poll timer; InternetTransport is the exception and must be polled.

All code in this crate is 100% safe Rust with no unsafe blocks.

Re-exports

pub use ble::BleTransport;

pub use ble::BleTransportBuilder;

pub use ble::FragmentEvictionCallback;

pub use ble::FragmentEvictionInfo;

pub use ble::PeerDevice;

pub use constants::DEFAULT_MAX_MESSAGE_SIZE;

pub use error::Error;

pub use error::Result;

pub use internet::InternetConfig;

pub use internet::InternetTransport;

pub use nostr::NostrConfig;

pub use nostr::NostrTransport;

pub use nostr::NostrTransportBuilder;

pub use nostr::SignedNostrEvent;

pub use nostr_crypto::routing_tag_for_address;

pub use nostr_crypto::NostrEvent;

pub use nostr_crypto::NostrKeypair;

pub use reticulum::ReticulumTransport;

pub use stream_framing::frame;

pub use stream_framing::CloseReason;

pub use stream_framing::PeerStreamReader;

pub use stream_framing::PreambleVerifier;

pub use stream_framing::StreamEvent;

pub use traits::Transport;

pub use traits::TransportStatus;

pub use types::LinkQuality;

pub use types::PeerLink;

pub use types::SharedCallback;

pub use types::TransportMetrics;

pub use types::TransportType;

pub use types::DEFAULT_LINK_QUALITY_WITHOUT_RSSI;

pub use wifi_direct::WifiDirectConfig;

pub use wifi_direct::WifiDirectPeer;

pub use wifi_direct::WifiDirectTransport;

Modules

ble

Bluetooth Low Energy (BLE) transport queue engine.

constants

Constants used throughout the offline-protocol-transport crate.

error

Transport layer errors.

internet

Internet transport (TCP/WebSocket relay) queue engine.

nostr

Nostr relay transport queue engine.

nostr_crypto

Nostr event creation and BIP-340 Schnorr signing.

reticulum

The gateway daemon transport’s queue engine.

stream_framing

Peer-stream framing: where a frame ends, and who the peer is.

traits

Transport trait definitions.

types

Transport types and data structures.

wifi_direct

The peer-stream transport: the queue engine behind the wifi_direct slot.