Introduce OffersMessageFlow

Author: shaavan

lightning/src/offers/flow.rs

@@ -0,0 +1,91 @@
+// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
+
+//! Provides data structures and functions for creating and managing Offers messages,
+//! facilitating communication, and handling Bolt12 messages and payments.
+
+use crate::ln::inbound_payment;
+use crate::onion_message::async_payments::AsyncPaymentsMessage;
+use crate::onion_message::messenger::{MessageRouter, MessageSendInstructions};
+use crate::onion_message::offers::OffersMessage;
+use crate::sign::EntropySource;
+use crate::sync::Mutex;
+use bitcoin::constants::ChainHash;
+use bitcoin::secp256k1::{PublicKey, Secp256k1};
+use bitcoin::{secp256k1, Network};
+
+use core::ops::Deref;
+use core::sync::atomic::AtomicUsize;
+
+#[cfg(feature = "dnssec")]
+use crate::onion_message::dns_resolution::DNSResolverMessage;
+
+pub struct OffersMessageFlow<ES: Deref, MR: Deref>
+where
+	ES::Target: EntropySource,
+	MR::Target: MessageRouter,
+{
+	chain_hash: ChainHash,
+	message_router: MR,
+
+	our_network_pubkey: PublicKey,
+	highest_seen_timestamp: AtomicUsize,
+	inbound_payment_key: inbound_payment::ExpandedKey,
+
+	secp_ctx: Secp256k1<secp256k1::All>,
+	entropy_source: ES,
+
+	#[cfg(not(any(test, feature = "_test_utils")))]
+	pending_offers_messages: Mutex<Vec<(OffersMessage, MessageSendInstructions)>>,
+	#[cfg(any(test, feature = "_test_utils"))]
+	pub(crate) pending_offers_messages: Mutex<Vec<(OffersMessage, MessageSendInstructions)>>,
+
+	pending_async_payments_messages: Mutex<Vec<(AsyncPaymentsMessage, MessageSendInstructions)>>,
+
+	#[cfg(feature = "dnssec")]
+	pending_dns_onion_messages: Mutex<Vec<(DNSResolverMessage, MessageSendInstructions)>>,
+}
+
+impl<ES: Deref, MR: Deref> OffersMessageFlow<ES, MR>
+where
+	ES::Target: EntropySource,
+	MR::Target: MessageRouter,
+{
+	/// Creates a new [`OffersMessageFlow`]
+	pub fn new(
+		network: Network, message_router: MR, our_network_pubkey: PublicKey,
+		current_timestamp: u32, inbound_payment_key: inbound_payment::ExpandedKey,
+		entropy_source: ES,
+	) -> Self {
+		let mut secp_ctx = Secp256k1::new();
+		secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
+
+		Self {
+			chain_hash: ChainHash::using_genesis_block(network),
+			message_router,
+
+			our_network_pubkey,
+			highest_seen_timestamp: AtomicUsize::new(current_timestamp as usize),
+			inbound_payment_key,
+
+			secp_ctx,
+			entropy_source,
+
+			pending_offers_messages: Mutex::new(Vec::new()),
+			pending_async_payments_messages: Mutex::new(Vec::new()),
+			#[cfg(feature = "dnssec")]
+			pending_dns_onion_messages: Mutex::new(Vec::new()),
+		}
+	}
+
+	/// Gets the node_id held by this OffersMessageFlow
+	pub fn get_our_node_id(&self) -> PublicKey {
+		self.our_network_pubkey
+	}
+}

lightning/src/offers/mod.rs

@@ -14,6 +14,7 @@
 
 #[macro_use]
 pub mod offer;
+pub mod flow;
 
 pub mod invoice;
 pub mod invoice_error;