Struct lightning::onion_message::OnionMessenger

pub struct OnionMessenger<ES: Deref, NS: Deref, L: Deref, CMH: Deref>where
    ES::Target: EntropySource,
    NS::Target: NodeSigner,
    L::Target: Logger,
    CMH::Target: CustomOnionMessageHandler,{ /* private fields */ }

A sender, receiver and forwarder of onion messages. In upcoming releases, this object will be used to retrieve invoices and fulfill invoice requests from offers. Currently, only sending and receiving custom onion messages is supported.

Example

// Create the onion messenger. This must use the same `keys_manager` as is passed to your
// ChannelManager.
let onion_messenger = OnionMessenger::new(&keys_manager, &keys_manager, logger, &your_custom_message_handler);

impl Writeable for YourCustomMessage {
	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
		// Write your custom onion message to `w`
	}
}
impl CustomOnionMessageContents for YourCustomMessage {
	fn tlv_type(&self) -> u64 {
		your_custom_message_type
	}
}
// Send a custom onion message to a node id.
let intermediate_hops = [hop_node_id1, hop_node_id2];
let reply_path = None;
let message = OnionMessageContents::Custom(your_custom_message);
onion_messenger.send_onion_message(&intermediate_hops, Destination::Node(destination_node_id), message, reply_path);

// Create a blinded path to yourself, for someone to send an onion message to.
let hops = [hop_node_id3, hop_node_id4, your_node_id];
let blinded_path = BlindedPath::new(&hops, &keys_manager, &secp_ctx).unwrap();

// Send a custom onion message to a blinded path.
let reply_path = None;
let message = OnionMessageContents::Custom(your_custom_message);
onion_messenger.send_onion_message(&intermediate_hops, Destination::BlindedPath(blinded_path), message, reply_path);

Implementations

impl<ES: Deref, NS: Deref, L: Deref, CMH: Deref> OnionMessenger<ES, NS, L, CMH>where ES::Target: EntropySource, NS::Target: NodeSigner, L::Target: Logger, CMH::Target: CustomOnionMessageHandler,

pub fn new( entropy_source: ES, node_signer: NS, logger: L, custom_handler: CMH ) -> Self

Constructs a new OnionMessenger to send, forward, and delegate received onion messages to their respective handlers.

pub fn send_onion_message<T: CustomOnionMessageContents>( &self, intermediate_nodes: &[PublicKey], destination: Destination, message: OnionMessageContents<T>, reply_path: Option<BlindedPath> ) -> Result<(), SendError>

Send an onion message with contents message to destination, routing it through intermediate_nodes. See OnionMessenger for example usage.

Trait Implementations

impl<ES: Deref, NS: Deref, L: Deref, CMH: Deref> OnionMessageHandler for OnionMessenger<ES, NS, L, CMH>where ES::Target: EntropySource, NS::Target: NodeSigner, L::Target: Logger, CMH::Target: CustomOnionMessageHandler + Sized,

fn handle_onion_message(&self, _peer_node_id: &PublicKey, msg: &OnionMessage)

Handle an incoming onion message. Currently, if a message was destined for us we will log, but soon we’ll delegate the onion message to a handler that can generate invoices or send payments.

fn peer_connected( &self, their_node_id: &PublicKey, init: &Init, _inbound: bool ) -> Result<(), ()>

Called when a connection is established with a peer. Can be used to track which peers advertise onion message support and are online.

fn peer_disconnected(&self, their_node_id: &PublicKey)

Indicates a connection to the peer failed/an existing connection was lost. Allows handlers to drop and refuse to forward onion messages to this peer.

fn provided_node_features(&self) -> NodeFeatures

Gets the node feature flags which this handler itself supports. All available handlers are queried similarly and their feature flags are OR’d together to form the NodeFeatures which are broadcasted in our NodeAnnouncement message.

fn provided_init_features(&self, _their_node_id: &PublicKey) -> InitFeatures

Gets the init feature flags which should be sent to the given peer. All available handlers are queried similarly and their feature flags are OR’d together to form the InitFeatures which are sent in our Init message.

impl<ES: Deref, NS: Deref, L: Deref, CMH: Deref> OnionMessageProvider for OnionMessenger<ES, NS, L, CMH>where ES::Target: EntropySource, NS::Target: NodeSigner, L::Target: Logger, CMH::Target: CustomOnionMessageHandler,

fn next_onion_message_for_peer( &self, peer_node_id: PublicKey ) -> Option<OnionMessage>

Gets the next pending onion message for the peer with the given node id.