feat: add cln payment processor

Author: Joseph Goulden

.gitignore

@@ -2,3 +2,4 @@
 nostr.db
 nostr.db-*
 justfile
+result

Cargo.lock

@@ -58,6 +58,7 @@ nostr = { version = "0.18.0", default-features = false, features = ["base", "nip
 log = "0.4"
 [target.'cfg(all(not(target_env = "msvc"), not(target_os = "openbsd")))'.dependencies]
 tikv-jemallocator = "0.5"
+cln-rpc = "0.1.9"
 
 [dev-dependencies]
 anyhow = "1"

Cargo.toml

@@ -203,18 +203,24 @@ limit_scrapers = false
 # Enable pay to relay
 #enabled = false
 
+# Node interface to use
+#processor = "ClnRest/LNBits"
+
 # The cost to be admitted to relay
 #admission_cost = 4200
 
 # The cost in sats per post
 #cost_per_event = 0
 
-# Url of lnbits api
+# Url of node api
 #node_url = "<node url>"
 
 # LNBits api secret
 #api_secret = "<ln bits api>"
 
+# Path to CLN rune
+#rune_path = "<rune path>"
+
 # Nostr direct message on signup
 #direct_message=false
 

config.toml

@@ -98,6 +98,7 @@ pub struct PayToRelay {
     pub direct_message: bool, // Send direct message to user with invoice and terms
     pub secret_key: Option<String>,
     pub processor: Processor,
+    pub rune_path: Option<String>, // To access clightning API
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -247,17 +248,25 @@ impl Settings {
 
         // Validate pay to relay settings
         if settings.pay_to_relay.enabled {
-            assert_ne!(settings.pay_to_relay.api_secret, "");
+            if settings.pay_to_relay.processor == Processor::ClnRest {
+                assert!(settings
+                    .pay_to_relay
+                    .rune_path
+                    .as_ref()
+                    .is_some_and(|path| path != "<rune path>"));
+            } else if settings.pay_to_relay.processor == Processor::LNBits {
+                assert_ne!(settings.pay_to_relay.api_secret, "");
+            }
             // Should check that url is valid
             assert_ne!(settings.pay_to_relay.node_url, "");
             assert_ne!(settings.pay_to_relay.terms_message, "");
 
             if settings.pay_to_relay.direct_message {
-                assert_ne!(
-                    settings.pay_to_relay.secret_key,
-                    Some("<nostr nsec>".to_string())
-                );
-                assert!(settings.pay_to_relay.secret_key.is_some());
+                assert!(settings
+                    .pay_to_relay
+                    .secret_key
+                    .as_ref()
+                    .is_some_and(|key| key != "<nostr nsec>"));
             }
         }
 
@@ -309,7 +318,7 @@ impl Default for Settings {
                 event_persist_buffer: 4096,
                 event_kind_blacklist: None,
                 event_kind_allowlist: None,
-                limit_scrapers: false
+                limit_scrapers: false,
             },
             authorization: Authorization {
                 pubkey_whitelist: None, // Allow any address to publish
@@ -323,6 +332,7 @@ impl Default for Settings {
                 terms_message: "".to_string(),
                 node_url: "".to_string(),
                 api_secret: "".to_string(),
+                rune_path: None,
                 sign_ups: false,
                 direct_message: false,
                 secret_key: None,

src/config.rs

@@ -42,7 +42,7 @@ pub enum Error {
     CommandUnknownError,
     #[error("SQL error")]
     SqlError(rusqlite::Error),
-    #[error("Config error")]
+    #[error("Config error : {0}")]
     ConfigError(config::ConfigError),
     #[error("Data directory does not exist")]
     DatabaseDirError,

src/error.rs

@@ -0,0 +1,137 @@
+use std::{fs, str::FromStr};
+
+use async_trait::async_trait;
+use cln_rpc::{
+    model::{
+        requests::InvoiceRequest,
+        responses::{InvoiceResponse, ListinvoicesInvoicesStatus, ListinvoicesResponse},
+    },
+    primitives::{Amount, AmountOrAny},
+};
+use config::ConfigError;
+use http::{header::CONTENT_TYPE, HeaderValue, Uri};
+use hyper::{client::HttpConnector, Client};
+use hyper_rustls::HttpsConnector;
+use nostr::Keys;
+use rand::random;
+
+use crate::{
+    config::Settings,
+    error::{Error, Result},
+};
+
+use super::{InvoiceInfo, InvoiceStatus, PaymentProcessor};
+
+#[derive(Clone)]
+pub struct ClnRestPaymentProcessor {
+    client: hyper::Client<HttpsConnector<HttpConnector>, hyper::Body>,
+    settings: Settings,
+    rune_header: HeaderValue,
+}
+
+impl ClnRestPaymentProcessor {
+    pub fn new(settings: &Settings) -> Result<Self> {
+        let rune_path = settings
+            .pay_to_relay
+            .rune_path
+            .clone()
+            .ok_or(ConfigError::NotFound("rune_path".to_string()))?;
+        let rune = String::from_utf8(fs::read(rune_path)?)
+            .map_err(|_| ConfigError::Message("Rune should be UTF8".to_string()))?;
+        let mut rune_header = HeaderValue::from_str(&rune.trim())
+            .map_err(|_| ConfigError::Message("Invalid Rune header".to_string()))?;
+        rune_header.set_sensitive(true);
+
+        let https = hyper_rustls::HttpsConnectorBuilder::new()
+            .with_native_roots()
+            .https_only()
+            .enable_http1()
+            .build();
+        let client = Client::builder().build::<_, hyper::Body>(https);
+
+        Ok(Self {
+            client,
+            settings: settings.clone(),
+            rune_header,
+        })
+    }
+}
+
+#[async_trait]
+impl PaymentProcessor for ClnRestPaymentProcessor {
+    async fn get_invoice(&self, key: &Keys, amount: u64) -> Result<InvoiceInfo, Error> {
+        let random_number: u16 = random();
+        let memo = format!("{}: {}", random_number, key.public_key());
+
+        let body = InvoiceRequest {
+            cltv: None,
+            deschashonly: None,
+            expiry: None,
+            preimage: None,
+            exposeprivatechannels: None,
+            fallbacks: None,
+            amount_msat: AmountOrAny::Amount(Amount::from_sat(amount)),
+            description: memo.clone(),
+            label: "Nostr".to_string(),
+        };
+        let uri = Uri::from_str(&format!(
+            "{}/v1/invoice",
+            &self.settings.pay_to_relay.node_url
+        ))
+        .map_err(|_| ConfigError::Message("Bad node URL".to_string()))?;
+
+        let req = hyper::Request::builder()
+            .method(hyper::Method::POST)
+            .uri(uri)
+            .header(CONTENT_TYPE, HeaderValue::from_static("application/json"))
+            .header("Rune", self.rune_header.clone())
+            .body(hyper::Body::from(serde_json::to_string(&body)?))
+            .expect("request builder");
+
+        let res = self.client.request(req).await?;
+
+        let body = hyper::body::to_bytes(res.into_body()).await?;
+        let invoice_response: InvoiceResponse = serde_json::from_slice(&body)?;
+
+        Ok(InvoiceInfo {
+            pubkey: key.public_key().to_string(),
+            payment_hash: invoice_response.payment_hash.to_string(),
+            bolt11: invoice_response.bolt11,
+            amount,
+            memo,
+            status: InvoiceStatus::Unpaid,
+            confirmed_at: None,
+        })
+    }
+
+    async fn check_invoice(&self, payment_hash: &str) -> Result<InvoiceStatus, Error> {
+        let uri = Uri::from_str(&format!(
+            "{}/v1/listinvoices?payment_hash={}",
+            &self.settings.pay_to_relay.node_url, payment_hash
+        ))
+        .map_err(|_| ConfigError::Message("Bad node URL".to_string()))?;
+
+        let req = hyper::Request::builder()
+            .method(hyper::Method::POST)
+            .uri(uri)
+            .header(CONTENT_TYPE, HeaderValue::from_static("application/json"))
+            .header("Rune", self.rune_header.clone())
+            .body(hyper::Body::empty())
+            .expect("request builder");
+
+        let res = self.client.request(req).await?;
+
+        let body = hyper::body::to_bytes(res.into_body()).await?;
+        let invoice_response: ListinvoicesResponse = serde_json::from_slice(&body)?;
+        let invoice = invoice_response
+            .invoices
+            .first()
+            .ok_or(Error::CustomError("Invoice not found".to_string()))?;
+        let status = match invoice.status {
+            ListinvoicesInvoicesStatus::PAID => InvoiceStatus::Paid,
+            ListinvoicesInvoicesStatus::UNPAID => InvoiceStatus::Unpaid,
+            ListinvoicesInvoicesStatus::EXPIRED => InvoiceStatus::Expired,
+        };
+        Ok(status)
+    }
+}