Add an endpoint to get the chain tip

firefly-cardanoconnect/src/main.rs

@@ -11,6 +11,7 @@ use config::{load_config, CardanoConnectConfig};
 use firefly_server::instrumentation;
 use persistence::Persistence;
 use routes::{
+    chain::get_chain_tip,
     health::health,
     streams::{
         create_listener, create_stream, delete_listener, delete_stream, get_listener, get_stream,
@@ -86,6 +87,7 @@ async fn main() -> Result<()> {
             "/api/eventstreams/:streamId/listeners/:listenerId",
             get(get_listener).delete(delete_listener),
         )
+        .api_route("/api/chain/tip", get(get_chain_tip))
         .route("/api/ws", axum::routing::get(handle_socket_upgrade))
         .with_state(state);
 

firefly-cardanoconnect/src/routes.rs

@@ -1,3 +1,4 @@
+pub mod chain;
 pub mod health;
 pub mod streams;
 pub mod transaction;

firefly-cardanoconnect/src/routes/chain.rs

@@ -0,0 +1,29 @@
+use axum::{extract::State, Json};
+use firefly_server::apitypes::{ApiError, ApiResult};
+use schemars::JsonSchema;
+use serde::Serialize;
+
+use crate::{blockchain::ChainSyncClient, AppState};
+
+#[derive(Serialize, JsonSchema)]
+#[serde(rename_all = "camelCase")]
+pub struct ChainTip {
+    pub block_height: Option<u64>,
+    pub block_slot: Option<u64>,
+    pub block_hash: String,
+}
+
+pub async fn get_chain_tip(
+    State(AppState { blockchain, .. }): State<AppState>,
+) -> ApiResult<Json<ChainTip>> {
+    let mut sync = blockchain.sync().await?;
+    let (_, tip) = sync.find_intersect(&[]).await?;
+    let Some(block) = sync.request_block(&tip).await? else {
+        return Err(ApiError::not_found("tip of chain not found"));
+    };
+    Ok(Json(ChainTip {
+        block_height: block.block_height,
+        block_slot: block.block_slot,
+        block_hash: block.block_hash,
+    }))
+}