fix(api): Healtcheck and api fixes (#360)

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---------

Signed-off-by: Danil <[email protected]>
Co-authored-by: Fedor Sakharov <[email protected]>

api/src/lib.rs

@@ -32,13 +32,21 @@ impl From<UserWithdrawal> for WithdrawalResponse {
 pub async fn run_server(pool: PgPool) {
     let app = Router::new()
         .route("/withdrawals/:from", get(get_withdrawals))
+        .route("/health", get(health))
         .with_state(pool);
 
     // run our app with hyper, listening globally on port 3000
     let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await.unwrap();
     axum::serve(listener, app).await.unwrap();
 }
 
+async fn health(State(pool): State<PgPool>) -> Result<&'static str, StatusCode> {
+    pool.acquire()
+        .await
+        .map_err(|_| StatusCode::INTERNAL_SERVER_ERROR)?;
+    Ok("ok")
+}
+
 async fn get_withdrawals(
     Path(from): Path<Address>,
     State(pool): State<PgPool>,

bin/withdrawal-finalizer/src/main.rs

@@ -15,7 +15,10 @@ use ethers::{
     types::U256,
 };
 use eyre::{anyhow, Result};
-use sqlx::{postgres::PgConnectOptions, ConnectOptions, PgConnection, PgPool};
+use sqlx::{
+    postgres::{PgConnectOptions, PgPoolOptions},
+    ConnectOptions, PgConnection,
+};
 
 use chain_events::{BlockEvents, L2EventsListener};
 use client::{l1bridge::codegen::IL1Bridge, zksync_contract::codegen::IZkSync, ZksyncMiddleware};
@@ -177,7 +180,10 @@ async fn main() -> Result<()> {
     let options =
         PgConnectOptions::from_str(config.database_url.as_str())?.disable_statement_logging();
 
-    let pgpool = PgPool::connect_with(options).await?;
+    let pgpool = PgPoolOptions::new()
+        .acquire_timeout(Duration::from_secs(2))
+        .connect_with(options)
+        .await?;
 
     let from_l2_block = start_from_l2_block(
         client_l2.clone(),