nostr: add support to ephemeral gift wrap

Signed-off-by: Yuki Kishimoto <[email protected]>

CHANGELOG.md

@@ -48,6 +48,7 @@
 * nostr: add `JsonUtil::try_as_json` method ([Yuki Kishimoto])
 * nostr: add `public_key` field to `TagStandard::Event` ([Yuki Kishimoto])
 * nostr: add support to `nrelay` NIP-19 entity ([Yuki Kishimoto])
+* nostr: add support to ephemeral gift wrap ([Yuki Kishimoto])
 * pool: allow to set event limits per kind ([Yuki Kishimoto])
 * pool: log warn when high latency ([Yuki Kishimoto])
 * sdk: add support to automatic authentication to relays (NIP-42) ([Yuki Kishimoto])

bindings/nostr-ffi/src/nips/nip59.rs

@@ -19,12 +19,14 @@ pub fn gift_wrap(
     sender_keys: &Keys,
     receiver_pubkey: &PublicKey,
     rumor: &UnsignedEvent,
+    ephemeral: bool,
     expiration: Option<Arc<Timestamp>>,
 ) -> Result<Event> {
     Ok(EventBuilder::gift_wrap(
         sender_keys.deref(),
         receiver_pubkey.deref(),
         rumor.deref().clone(),
+        ephemeral,
         expiration.map(|t| **t),
     )?
     .into())
@@ -37,12 +39,16 @@ pub fn gift_wrap(
 pub fn gift_wrap_from_seal(
     receiver: &PublicKey,
     seal: &Event,
+    ephemeral: bool,
     expiration: Option<Arc<Timestamp>>,
 ) -> Result<Event> {
-    Ok(
-        EventBuilder::gift_wrap_from_seal(receiver.deref(), seal.deref(), expiration.map(|t| **t))?
-            .into(),
-    )
+    Ok(EventBuilder::gift_wrap_from_seal(
+        receiver.deref(),
+        seal.deref(),
+        ephemeral,
+        expiration.map(|t| **t),
+    )?
+    .into())
 }
 
 /// Unwrapped Gift Wrap

bindings/nostr-js/src/event/builder.rs

@@ -561,11 +561,13 @@ impl JsEventBuilder {
     pub fn gift_wrap_from_seal(
         receiver: &JsPublicKey,
         seal: &JsEvent,
+        ephemeral: bool,
         expiration: Option<JsTimestamp>,
     ) -> Result<JsEvent> {
         Ok(EventBuilder::gift_wrap_from_seal(
             receiver.deref(),
             seal.deref(),
+            ephemeral,
             expiration.map(|t| *t),
         )
         .map_err(into_err)?
@@ -580,12 +582,14 @@ impl JsEventBuilder {
         sender_keys: &JsKeys,
         receiver: &JsPublicKey,
         rumor: &JsUnsignedEvent,
+        ephemeral: bool,
         expiration: Option<JsTimestamp>,
     ) -> Result<JsEvent> {
         Ok(EventBuilder::gift_wrap(
             sender_keys.deref(),
             receiver.deref(),
             rumor.deref().clone(),
+            ephemeral,
             expiration.map(|t| *t),
         )
         .map_err(into_err)?

bindings/nostr-sdk-js/src/database.rs

@@ -54,6 +54,7 @@ impl JsNostrDatabase {
     pub async fn save_event(&self, event: &JsEvent) -> Result<bool> {
         self.inner.save_event(event).await.map_err(into_err)
     }
+
     /// Get list of relays that have seen the [`EventId`]
     #[wasm_bindgen(js_name = eventSeenOnRelays)]
     pub async fn event_seen_on_relays(

crates/nostr-sdk/src/client/mod.rs

@@ -1240,7 +1240,7 @@ impl Client {
         S: Into<String>,
     {
         let rumor: EventBuilder = EventBuilder::private_msg_rumor(receiver, message, reply_to);
-        self.gift_wrap(receiver, rumor, None).await
+        self.gift_wrap(receiver, rumor, false, None).await
     }
 
     /// Repost
@@ -1475,6 +1475,7 @@ impl Client {
         &self,
         receiver: PublicKey,
         rumor: EventBuilder,
+        ephemeral: bool,
         expiration: Option<Timestamp>,
     ) -> Result<(), Error> {
         // Compose rumor
@@ -1490,7 +1491,8 @@ impl Client {
         let seal: Event = self.sign_event_builder(seal).await?;
 
         // Compose gift wrap
-        let gift_wrap: Event = EventBuilder::gift_wrap_from_seal(&receiver, &seal, expiration)?;
+        let gift_wrap: Event =
+            EventBuilder::gift_wrap_from_seal(&receiver, &seal, ephemeral, expiration)?;
 
         // Send event
         self.send_event(gift_wrap).await?;

crates/nostr/src/event/builder.rs

@@ -1319,7 +1319,8 @@ impl EventBuilder {
     pub fn gift_wrap_from_seal(
         receiver: &PublicKey,
         seal: &Event,
-        expiration: Option<Timestamp>,
+        ephemeral: bool,
+        expiration: Option<Timestamp>, // TODO: remove this and add `EventBuilder::expiration`?
     ) -> Result<Event, Error> {
         if seal.kind != Kind::Seal {
             return Err(Error::WrongKind {
@@ -1343,7 +1344,13 @@ impl EventBuilder {
             tags.push(Tag::expiration(timestamp));
         }
 
-        Self::new(Kind::GiftWrap, content, tags)
+        let kind: Kind = if ephemeral {
+            Kind::EphemeralGiftWrap
+        } else {
+            Kind::GiftWrap
+        };
+
+        Self::new(kind, content, tags)
             .custom_created_at(Timestamp::tweaked(nip59::RANGE_RANDOM_TIMESTAMP_TWEAK))
             .to_event(&keys)
     }
@@ -1357,10 +1364,11 @@ impl EventBuilder {
         sender_keys: &Keys,
         receiver: &PublicKey,
         rumor: UnsignedEvent,
-        expiration: Option<Timestamp>,
+        ephemeral: bool,
+        expiration: Option<Timestamp>, // TODO: remove this and add `EventBuilder::expiration`?
     ) -> Result<Event, Error> {
         let seal: Event = Self::seal(sender_keys, receiver, rumor)?.to_event(sender_keys)?;
-        Self::gift_wrap_from_seal(receiver, &seal, expiration)
+        Self::gift_wrap_from_seal(receiver, &seal, ephemeral, expiration)
     }
 
     /// GiftWrapped Sealed Direct message

crates/nostr/src/event/kind.rs

@@ -137,6 +137,7 @@ kind_variants! {
     BadgeDefinition => 30009, "Badge Definition (NIP58)",
     Seal => 13, "Seal <https://github.com/nostr-protocol/nips/blob/master/59.md>",
     GiftWrap => 1059, "Gift Wrap <https://github.com/nostr-protocol/nips/blob/master/59.md>",
+    EphemeralGiftWrap => 21059, "Ephemeral Gift Wrap",
     PrivateDirectMessage => 14, "Private Direct message <https://github.com/nostr-protocol/nips/blob/master/17.md>",
     SetStall => 30017, "Set stall (NIP15)",
     SetProduct => 30018, "Set product (NIP15)",

crates/nostr/src/nips/nip59.rs

@@ -107,7 +107,7 @@ impl UnwrappedGift {
         C: Verification,
     {
         // Check event kind
-        if gift_wrap.kind != Kind::GiftWrap {
+        if gift_wrap.kind != Kind::GiftWrap && gift_wrap.kind != Kind::EphemeralGiftWrap {
             return Err(Error::NotGiftWrap);
         }
 
@@ -161,6 +161,7 @@ mod tests {
             &sender_keys,
             &receiver_keys.public_key(),
             rumor.clone(),
+            false,
             None,
         )
         .unwrap();