refactor(hermes): state->price_feed_metadata downcasting

hermes/src/aggregate.rs

@@ -426,7 +426,7 @@ where
 
 pub async fn is_ready(state: &State) -> bool {
     let metadata = state.aggregate_state.read().await;
-    let price_feeds_metadata = state.price_feeds_metadata.read().await;
+    let price_feeds_metadata = state.price_feed_meta.data.read().await;
 
     let has_completed_recently = match metadata.latest_completed_update_at.as_ref() {
         Some(latest_completed_update_time) => {
@@ -456,7 +456,7 @@ mod test {
         super::*,
         crate::{
             api::types::PriceFeedMetadata,
-            price_feeds_metadata::store_price_feeds_metadata,
+            price_feeds_metadata::PriceFeedMeta,
             state::test::setup_state,
         },
         futures::future::join_all,
@@ -809,15 +809,13 @@ mod test {
 
 
         // Add a dummy price feeds metadata
-        store_price_feeds_metadata(
-            &state,
-            &[PriceFeedMetadata {
+        state
+            .store_price_feeds_metadata(&[PriceFeedMetadata {
                 id:         PriceIdentifier::new([100; 32]),
                 attributes: Default::default(),
-            }],
-        )
-        .await
-        .unwrap();
+            }])
+            .await
+            .unwrap();
 
         // Check the state is ready
         assert!(is_ready(&state).await);

hermes/src/api.rs

@@ -26,15 +26,27 @@ mod rest;
 pub mod types;
 mod ws;
 
-#[derive(Clone)]
-pub struct ApiState {
-    pub state:     Arc<State>,
+pub struct ApiState<S = State> {
+    pub state:     Arc<S>,
     pub ws:        Arc<ws::WsState>,
     pub metrics:   Arc<metrics_middleware::Metrics>,
     pub update_tx: Sender<AggregationEvent>,
 }
 
-impl ApiState {
+/// Manually implement `Clone` as the derive macro will try and slap `Clone` on
+/// `State` which should not be Clone.
+impl<S> Clone for ApiState<S> {
+    fn clone(&self) -> Self {
+        Self {
+            state:     self.state.clone(),
+            ws:        self.ws.clone(),
+            metrics:   self.metrics.clone(),
+            update_tx: self.update_tx.clone(),
+        }
+    }
+}
+
+impl ApiState<State> {
     pub fn new(
         state: Arc<State>,
         ws_whitelist: Vec<IpNet>,

hermes/src/api/rest/v2/price_feeds_metadata.rs

@@ -6,8 +6,9 @@ use {
                 AssetType,
                 PriceFeedMetadata,
             },
+            ApiState,
         },
-        price_feeds_metadata::get_price_feeds_metadata,
+        price_feeds_metadata::PriceFeedMeta,
     },
     anyhow::Result,
     axum::{
@@ -46,19 +47,23 @@ pub struct PriceFeedsMetadataQueryParams {
         PriceFeedsMetadataQueryParams
     )
 )]
-pub async fn price_feeds_metadata(
-    State(state): State<crate::api::ApiState>,
+pub async fn price_feeds_metadata<S>(
+    State(state): State<ApiState<S>>,
     QsQuery(params): QsQuery<PriceFeedsMetadataQueryParams>,
-) -> Result<Json<Vec<PriceFeedMetadata>>, RestError> {
-    let price_feeds_metadata =
-        get_price_feeds_metadata(&state.state, params.query, params.asset_type)
-            .await
-            .map_err(|e| {
-                tracing::warn!("RPC connection error: {}", e);
-                RestError::RpcConnectionError {
-                    message: format!("RPC connection error: {}", e),
-                }
-            })?;
+) -> Result<Json<Vec<PriceFeedMetadata>>, RestError>
+where
+    S: PriceFeedMeta,
+{
+    let state = &state.state;
+    let price_feeds_metadata = state
+        .get_price_feeds_metadata(params.query, params.asset_type)
+        .await
+        .map_err(|e| {
+            tracing::warn!("RPC connection error: {}", e);
+            RestError::RpcConnectionError {
+                message: format!("RPC connection error: {}", e),
+            }
+        })?;
 
     Ok(Json(price_feeds_metadata))
 }

hermes/src/network/pythnet.rs

@@ -17,7 +17,7 @@ use {
             GuardianSetData,
         },
         price_feeds_metadata::{
-            store_price_feeds_metadata,
+            PriceFeedMeta,
             DEFAULT_PRICE_FEEDS_CACHE_UPDATE_INTERVAL,
         },
         state::State,
@@ -353,13 +353,18 @@ pub async fn spawn(opts: RunOptions, state: Arc<State>) -> Result<()> {
 }
 
 
-pub async fn fetch_and_store_price_feeds_metadata(
-    state: &State,
+pub async fn fetch_and_store_price_feeds_metadata<S>(
+    state: &S,
     mapping_address: &Pubkey,
     rpc_client: &RpcClient,
-) -> Result<Vec<PriceFeedMetadata>> {
+) -> Result<Vec<PriceFeedMetadata>>
+where
+    S: PriceFeedMeta,
+{
     let price_feeds_metadata = fetch_price_feeds_metadata(mapping_address, rpc_client).await?;
-    store_price_feeds_metadata(state, &price_feeds_metadata).await?;
+    state
+        .store_price_feeds_metadata(&price_feeds_metadata)
+        .await?;
     Ok(price_feeds_metadata)
 }
 

hermes/src/price_feeds_metadata.rs

@@ -7,49 +7,88 @@ use {
         state::State,
     },
     anyhow::Result,
+    tokio::sync::RwLock,
 };
 
 pub const DEFAULT_PRICE_FEEDS_CACHE_UPDATE_INTERVAL: u64 = 600;
 
-pub async fn retrieve_price_feeds_metadata(state: &State) -> Result<Vec<PriceFeedMetadata>> {
-    let price_feeds_metadata = state.price_feeds_metadata.read().await;
-    Ok(price_feeds_metadata.clone())
+pub struct PriceFeedMetaState {
+    pub data: RwLock<Vec<PriceFeedMetadata>>,
 }
 
-pub async fn store_price_feeds_metadata(
-    state: &State,
-    price_feeds_metadata: &[PriceFeedMetadata],
-) -> Result<()> {
-    let mut price_feeds_metadata_write_guard = state.price_feeds_metadata.write().await;
-    *price_feeds_metadata_write_guard = price_feeds_metadata.to_vec();
-    Ok(())
+impl PriceFeedMetaState {
+    pub fn new() -> Self {
+        Self {
+            data: RwLock::new(Vec::new()),
+        }
+    }
 }
 
+/// Allow downcasting State into CacheState for functions that depend on the `Cache` service.
+impl<'a> From<&'a State> for &'a PriceFeedMetaState {
+    fn from(state: &'a State) -> &'a PriceFeedMetaState {
+        &state.price_feed_meta
+    }
+}
+
+pub trait PriceFeedMeta {
+    async fn retrieve_price_feeds_metadata(&self) -> Result<Vec<PriceFeedMetadata>>;
+    async fn store_price_feeds_metadata(
+        &self,
+        price_feeds_metadata: &[PriceFeedMetadata],
+    ) -> Result<()>;
+    async fn get_price_feeds_metadata(
+        &self,
+        query: Option<String>,
+        asset_type: Option<AssetType>,
+    ) -> Result<Vec<PriceFeedMetadata>>;
+}
 
-pub async fn get_price_feeds_metadata(
-    state: &State,
-    query: Option<String>,
-    asset_type: Option<AssetType>,
-) -> Result<Vec<PriceFeedMetadata>> {
-    let mut price_feeds_metadata = retrieve_price_feeds_metadata(state).await?;
-
-    // Filter by query if provided
-    if let Some(query_str) = &query {
-        price_feeds_metadata.retain(|feed| {
-            feed.attributes.get("symbol").map_or(false, |symbol| {
-                symbol.to_lowercase().contains(&query_str.to_lowercase())
-            })
-        });
+impl<T> PriceFeedMeta for T
+where
+    for<'a> &'a T: Into<&'a PriceFeedMetaState>,
+    T: Sync,
+{
+    async fn retrieve_price_feeds_metadata(&self) -> Result<Vec<PriceFeedMetadata>> {
+        let price_feeds_metadata = self.into().data.read().await;
+        Ok(price_feeds_metadata.clone())
     }
 
-    // Filter by asset_type if provided
-    if let Some(asset_type) = &asset_type {
-        price_feeds_metadata.retain(|feed| {
-            feed.attributes.get("asset_type").map_or(false, |type_str| {
-                type_str.to_lowercase() == asset_type.to_string().to_lowercase()
-            })
-        });
+    async fn store_price_feeds_metadata(
+        &self,
+        price_feeds_metadata: &[PriceFeedMetadata],
+    ) -> Result<()> {
+        let mut price_feeds_metadata_write_guard = self.into().data.write().await;
+        *price_feeds_metadata_write_guard = price_feeds_metadata.to_vec();
+        Ok(())
     }
 
-    Ok(price_feeds_metadata)
+
+    async fn get_price_feeds_metadata(
+        &self,
+        query: Option<String>,
+        asset_type: Option<AssetType>,
+    ) -> Result<Vec<PriceFeedMetadata>> {
+        let mut price_feeds_metadata = self.retrieve_price_feeds_metadata().await?;
+
+        // Filter by query if provided
+        if let Some(query_str) = &query {
+            price_feeds_metadata.retain(|feed| {
+                feed.attributes.get("symbol").map_or(false, |symbol| {
+                    symbol.to_lowercase().contains(&query_str.to_lowercase())
+                })
+            });
+        }
+
+        // Filter by asset_type if provided
+        if let Some(asset_type) = &asset_type {
+            price_feeds_metadata.retain(|feed| {
+                feed.attributes.get("asset_type").map_or(false, |type_str| {
+                    type_str.to_lowercase() == asset_type.to_string().to_lowercase()
+                })
+            });
+        }
+
+        Ok(price_feeds_metadata)
+    }
 }

hermes/src/state.rs

@@ -10,8 +10,8 @@ use {
             AggregateState,
             AggregationEvent,
         },
-        api::types::PriceFeedMetadata,
         network::wormhole::GuardianSet,
+        price_feeds_metadata::PriceFeedMetaState,
     },
     prometheus_client::registry::Registry,
     reqwest::Url,
@@ -38,6 +38,9 @@ pub struct State {
     /// State for the `Benchmarks` service for looking up historical updates.
     pub benchmarks: BenchmarksState,
 
+    /// State for the `PriceFeedMeta` service for looking up metadata related to Pyth price feeds.
+    pub price_feed_meta: PriceFeedMetaState,
+
     /// Sequence numbers of lately observed Vaas. Store uses this set
     /// to ignore the previously observed Vaas as a performance boost.
     pub observed_vaa_seqs: RwLock<BTreeSet<u64>>,
@@ -53,9 +56,6 @@ pub struct State {
 
     /// Metrics registry
     pub metrics_registry: RwLock<Registry>,
-
-    /// Price feeds metadata
-    pub price_feeds_metadata: RwLock<Vec<PriceFeedMetadata>>,
 }
 
 impl State {
@@ -66,14 +66,14 @@ impl State {
     ) -> Arc<Self> {
         let mut metrics_registry = Registry::default();
         Arc::new(Self {
-            cache:                CacheState::new(cache_size),
-            benchmarks:           BenchmarksState::new(benchmarks_endpoint),
-            observed_vaa_seqs:    RwLock::new(Default::default()),
-            guardian_set:         RwLock::new(Default::default()),
-            api_update_tx:        update_tx,
-            aggregate_state:      RwLock::new(AggregateState::new(&mut metrics_registry)),
-            metrics_registry:     RwLock::new(metrics_registry),
-            price_feeds_metadata: RwLock::new(Default::default()),
+            cache:             CacheState::new(cache_size),
+            benchmarks:        BenchmarksState::new(benchmarks_endpoint),
+            price_feed_meta:   PriceFeedMetaState::new(),
+            observed_vaa_seqs: RwLock::new(Default::default()),
+            guardian_set:      RwLock::new(Default::default()),
+            api_update_tx:     update_tx,
+            aggregate_state:   RwLock::new(AggregateState::new(&mut metrics_registry)),
+            metrics_registry:  RwLock::new(metrics_registry),
         })
     }
 }