feat(gossipsub): add getter function to obtain TopicScoreParams

Added a getter function to obtain `TopicScoreParams`. I need this function for testing which checks if scoring parameters are updated as expected.

Pull-Request: #4231.

protocols/gossipsub/CHANGELOG.md

@@ -1,4 +1,11 @@
-## 0.45.0 
+## 0.45.1 - unreleased
+
+- Add getter function to obtain `TopicScoreParams`.
+  See [PR 4231].
+
+[PR 4231]: https://github.com/libp2p/rust-libp2p/pull/4231
+
+## 0.45.0
 
 - Raise MSRV to 1.65.
   See [PR 3715].

protocols/gossipsub/Cargo.toml

@@ -3,7 +3,7 @@ name = "libp2p-gossipsub"
 edition = "2021"
 rust-version = { workspace = true }
 description = "Gossipsub protocol for libp2p"
-version = "0.45.0"
+version = "0.45.1"
 authors = ["Age Manning <Age@AgeManning.com>"]
 license = "MIT"
 repository = "https://github.com/libp2p/rust-libp2p"

protocols/gossipsub/src/behaviour.rs

@@ -930,6 +930,11 @@ where
         }
     }
 
+    /// Returns a scoring parameters for a topic if existent.
+    pub fn get_topic_params<H: Hasher>(&self, topic: &Topic<H>) -> Option<&TopicScoreParams> {
+        self.peer_score.as_ref()?.0.get_topic_params(&topic.hash())
+    }
+
     /// Sets the application specific score for a peer. Returns true if scoring is active and
     /// the peer is connected or if the score of the peer is not yet expired, false otherwise.
     pub fn set_application_score(&mut self, peer_id: &PeerId, new_score: f64) -> bool {

protocols/gossipsub/src/peer_score.rs

@@ -780,6 +780,11 @@ impl PeerScore {
         }
     }
 
+    /// Returns a scoring parameters for a topic if existent.
+    pub(crate) fn get_topic_params(&self, topic_hash: &TopicHash) -> Option<&TopicScoreParams> {
+        self.params.topics.get(topic_hash)
+    }
+
     /// Increments the "invalid message deliveries" counter for all scored topics the message
     /// is published in.
     fn mark_invalid_message_delivery(&mut self, peer_id: &PeerId, topic_hash: &TopicHash) {