nostr: refactor NIP-17 relay list extraction functions to use impl Iterator

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

Author: yukibtc

crates/nostr/src/nips/nip17.rs

@@ -6,37 +6,26 @@
 //!
 //! <https://github.com/nostr-protocol/nips/blob/master/17.md>
 
-use alloc::boxed::Box;
-use core::iter;
-
-use crate::{Event, Kind, RelayUrl, TagStandard};
+use crate::{Event, RelayUrl, TagStandard};
 
 /// Extracts the relay list
-pub fn extract_relay_list<'a>(event: &'a Event) -> Box<dyn Iterator<Item = &'a RelayUrl> + 'a> {
-    if event.kind != Kind::InboxRelays {
-        return Box::new(iter::empty());
-    }
-
-    Box::new(event.tags.iter().filter_map(|tag| {
+pub fn extract_relay_list(event: &Event) -> impl Iterator<Item = &RelayUrl> {
+    event.tags.iter().filter_map(|tag| {
         if let Some(TagStandard::Relay(url)) = tag.as_standardized() {
             Some(url)
         } else {
             None
         }
-    }))
+    })
 }
 
 /// Extracts the relay list
-pub fn extract_owned_relay_list(event: Event) -> Box<dyn Iterator<Item = RelayUrl>> {
-    if event.kind != Kind::InboxRelays {
-        return Box::new(iter::empty());
-    }
-
-    Box::new(event.tags.into_iter().filter_map(|tag| {
+pub fn extract_owned_relay_list(event: Event) -> impl Iterator<Item = RelayUrl> {
+    event.tags.into_iter().filter_map(|tag| {
         if let Some(TagStandard::Relay(url)) = tag.to_standardized() {
             Some(url)
         } else {
             None
         }
-    }))
+    })
 }