Abstract payjoin into well reasoned functions

Author: DanGould

mutiny-core/src/lib.rs

@@ -1502,61 +1502,26 @@ impl<S: MutinyStorage> MutinyWallet<S> {
             return Err(MutinyError::WalletOperationFailed);
         };
 
-        let (pj, ohttp) = {
-            use crate::payjoin::{OHTTP_RELAYS, PAYJOIN_DIR};
-            use anyhow::anyhow;
-
-            let ohttp_keys = crate::payjoin::fetch_ohttp_keys(
-                OHTTP_RELAYS[0].to_owned(),
-                PAYJOIN_DIR.to_owned(),
-            )
-            .await
-            .map_err(|e| anyhow!("Payjoin OHTTP fetch error {}", e))?;
-
-            let ohttp = base64::encode_config(
-                ohttp_keys
-                    .encode()
-                    .map_err(|_| MutinyError::PayjoinConfigError)?,
-                base64::URL_SAFE_NO_PAD,
-            );
-            let mut enroller = pj::receive::v2::Enroller::from_directory_config(
-                PAYJOIN_DIR.to_owned(),
-                ohttp_keys,
-                OHTTP_RELAYS[0].to_owned(), // TODO pick ohttp relay at random
-            );
-
-            // enroll client
-            let (req, context) = enroller.extract_req().unwrap();
-            let http_client = reqwest::Client::builder().build().unwrap();
-            let ohttp_response = http_client
-                .post(req.url)
-                .header("Content-Type", "message/ohttp-req")
-                .body(req.body)
-                .send()
-                .await
-                .map_err(|_| MutinyError::PayjoinCreateRequest)?;
-            let ohttp_response = ohttp_response.bytes().await.unwrap();
-            let enrolled = enroller
-                .process_res(ohttp_response.as_ref(), context)
-                .map_err(|_| MutinyError::PayjoinCreateRequest)?;
-            let session = self
-                .node_manager
-                .storage
-                .persist_payjoin(enrolled.clone())?;
-            let pj_uri = enrolled.fallback_target();
-            log_debug!(self.logger, "{pj_uri}");
-            let wallet = self.node_manager.wallet.clone();
-            let stop = self.node_manager.stop.clone();
-            let storage = Arc::new(self.node_manager.storage.clone());
-            // run await payjoin task in the background as it'll keep polling the relay
-            let logger = self.logger.clone();
-            utils::spawn(async move {
-                match NodeManager::receive_payjoin(wallet, stop, storage, session).await {
-                    Ok(pj_txid) => log_info!(logger, "Received payjoin txid: {}", pj_txid),
-                    Err(e) => log_error!(logger, "Payjoin error: {e}"),
-                }
-            });
-            (Some(pj_uri), Some(ohttp))
+        let (pj, ohttp) = match self.node_manager.start_payjoin_session().await {
+            Ok((enrolled, ohttp_keys)) => {
+                let session = self
+                    .node_manager
+                    .storage
+                    .persist_payjoin(enrolled.clone())?;
+                let pj_uri = session.enrolled.fallback_target();
+                self.node_manager.spawn_payjoin_receiver(session);
+                let ohttp = base64::encode_config(
+                    ohttp_keys
+                        .encode()
+                        .map_err(|_| MutinyError::PayjoinConfigError)?,
+                    base64::URL_SAFE_NO_PAD,
+                );
+                (Some(pj_uri), Some(ohttp))
+            }
+            Err(e) => {
+                log_error!(self.logger, "Error enrolling payjoin: {e}");
+                (None, None)
+            }
         };
 
         Ok(MutinyBip21RawMaterials {

mutiny-core/src/nodemanager.rs

@@ -3,7 +3,7 @@ use crate::event::HTLCStatus;
 use crate::labels::LabelStorage;
 use crate::ldkstorage::CHANNEL_CLOSURE_PREFIX;
 use crate::logging::LOGGING_KEY;
-use crate::payjoin::PayjoinStorage;
+use crate::payjoin::{Error as PayjoinError, PayjoinStorage};
 use crate::utils::{sleep, spawn};
 use crate::ActivityItem;
 use crate::MutinyInvoice;
@@ -55,7 +55,9 @@ use lightning::util::logger::*;
 use lightning::{log_debug, log_error, log_info, log_trace, log_warn};
 use lightning_invoice::Bolt11Invoice;
 use lightning_transaction_sync::EsploraSyncClient;
+use payjoin::receive::v2::Enrolled;
 use payjoin::Uri;
+use pj::OhttpKeys;
 use reqwest::Client;
 use serde::{Deserialize, Serialize};
 use serde_json::Value;
@@ -633,15 +635,7 @@ impl<S: MutinyStorage> NodeManager<S> {
     pub(crate) fn resume_payjoins(nm: Arc<NodeManager<S>>) {
         let all = nm.storage.get_payjoins().unwrap_or_default();
         for payjoin in all {
-            let wallet = nm.wallet.clone();
-            let stop = nm.stop.clone();
-            let storage = Arc::new(nm.storage.clone());
-            utils::spawn(async move {
-                let pj_txid = Self::receive_payjoin(wallet, stop, storage, payjoin)
-                    .await
-                    .unwrap();
-                log::info!("Received payjoin txid: {}", pj_txid);
-            });
+            nm.clone().spawn_payjoin_receiver(payjoin);
         }
     }
 
@@ -734,6 +728,33 @@ impl<S: MutinyStorage> NodeManager<S> {
         Err(MutinyError::WalletOperationFailed)
     }
 
+    pub async fn start_payjoin_session(&self) -> Result<(Enrolled, OhttpKeys), PayjoinError> {
+        use crate::payjoin::{OHTTP_RELAYS, PAYJOIN_DIR};
+
+        let ohttp_keys =
+            crate::payjoin::fetch_ohttp_keys(OHTTP_RELAYS[0].to_owned(), PAYJOIN_DIR.to_owned())
+                .await?;
+        let http_client = reqwest::Client::builder().build()?;
+
+        let mut enroller = payjoin::receive::v2::Enroller::from_directory_config(
+            PAYJOIN_DIR.to_owned(),
+            ohttp_keys.clone(),
+            OHTTP_RELAYS[0].to_owned(), // TODO pick ohttp relay at random
+        );
+        let (req, context) = enroller.extract_req()?;
+        let ohttp_response = http_client
+            .post(req.url)
+            .header("Content-Type", "message/ohttp-req")
+            .body(req.body)
+            .send()
+            .await?;
+        let ohttp_response = ohttp_response.bytes().await?;
+        Ok((
+            enroller.process_res(ohttp_response.as_ref(), context)?,
+            ohttp_keys,
+        ))
+    }
+
     // Send v1 payjoin request
     pub async fn send_payjoin(
         &self,
@@ -809,15 +830,26 @@ impl<S: MutinyStorage> NodeManager<S> {
         Ok(txid)
     }
 
+    pub fn spawn_payjoin_receiver(&self, session: crate::payjoin::Session) {
+        let logger = self.logger.clone();
+        let wallet = self.wallet.clone();
+        let stop = self.stop.clone();
+        let storage = Arc::new(self.storage.clone());
+        utils::spawn(async move {
+            match Self::receive_payjoin(wallet, stop, storage, session).await {
+                Ok(txid) => log_info!(logger, "Received payjoin txid: {txid}"),
+                Err(e) => log_error!(logger, "Error receiving payjoin: {e}"),
+            };
+        });
+    }
+
     /// Poll the payjoin relay to maintain a payjoin session and create a payjoin proposal.
-    pub async fn receive_payjoin(
+    async fn receive_payjoin(
         wallet: Arc<OnChainWallet<S>>,
         stop: Arc<AtomicBool>,
         storage: Arc<S>,
         mut session: crate::payjoin::Session,
     ) -> Result<Txid, MutinyError> {
-        use crate::payjoin::Error as PayjoinError;
-
         let http_client = reqwest::Client::builder()
             .build()
             .map_err(PayjoinError::Reqwest)?;

mutiny-core/src/payjoin.rs

@@ -69,10 +69,7 @@ impl<S: MutinyStorage> PayjoinStorage for S {
     }
 }
 
-pub async fn fetch_ohttp_keys(
-    _ohttp_relay: Url,
-    directory: Url,
-) -> Result<OhttpKeys, Box<dyn std::error::Error>> {
+pub async fn fetch_ohttp_keys(_ohttp_relay: Url, directory: Url) -> Result<OhttpKeys, Error> {
     let http_client = reqwest::Client::builder().build()?;
 
     let ohttp_keys_res = http_client
@@ -81,14 +78,15 @@ pub async fn fetch_ohttp_keys(
         .await?
         .bytes()
         .await?;
-    Ok(OhttpKeys::decode(ohttp_keys_res.as_ref())?)
+    Ok(OhttpKeys::decode(ohttp_keys_res.as_ref()).map_err(|_| Error::OhttpDecodeFailed)?)
 }
 
 #[derive(Debug)]
 pub enum Error {
     Reqwest(reqwest::Error),
     ReceiverStateMachine(String),
     Txid(bitcoin::hashes::hex::Error),
+    OhttpDecodeFailed,
     Shutdown,
     SessionExpired,
 }
@@ -101,6 +99,7 @@ impl std::fmt::Display for Error {
             Error::Reqwest(e) => write!(f, "Reqwest error: {}", e),
             Error::ReceiverStateMachine(e) => write!(f, "Payjoin state machine error: {}", e),
             Error::Txid(e) => write!(f, "Payjoin txid error: {}", e),
+            Error::OhttpDecodeFailed => write!(f, "Failed to decode ohttp keys"),
             Error::Shutdown => write!(f, "Payjoin stopped by application shutdown"),
             Error::SessionExpired => write!(f, "Payjoin session expired. Create a new payment request and have the sender try again."),
         }