From 2ce48420e71fc58d6406c15ae44bbc7ea987677a Mon Sep 17 00:00:00 2001
From: Tristan <122918260+TAdev0@users.noreply.github.com>
Date: Tue, 5 Dec 2023 20:12:13 +0100
Subject: [PATCH] FEAT: add healthCheck to KKRT Net API (#662)

* healthCheck

* health-check

* health-check
---
 crates/eth-rpc/src/api/net_api.rs     |  5 +++++
 crates/eth-rpc/src/rpc.rs             |  4 ++--
 crates/eth-rpc/src/servers/net_rpc.rs | 25 +++++++++++++++++++------
 crates/eth-rpc/tests/integration.rs   |  8 ++++++++
 4 files changed, 34 insertions(+), 8 deletions(-)

diff --git a/crates/eth-rpc/src/api/net_api.rs b/crates/eth-rpc/src/api/net_api.rs
index a63e918d3..648a204af 100644
--- a/crates/eth-rpc/src/api/net_api.rs
+++ b/crates/eth-rpc/src/api/net_api.rs
@@ -19,4 +19,9 @@ pub trait NetApi {
     /// Otherwise false.
     #[method(name = "listening")]
     fn listening(&self) -> Result<bool>;
+
+    /// Returns true if Kakarot RPC_URL is reachable.
+    /// Otherwise throw an EthApiError.
+    #[method(name = "health")]
+    async fn health(&self) -> Result<bool>;
 }
diff --git a/crates/eth-rpc/src/rpc.rs b/crates/eth-rpc/src/rpc.rs
index be86e3227..a4b5c7ccf 100644
--- a/crates/eth-rpc/src/rpc.rs
+++ b/crates/eth-rpc/src/rpc.rs
@@ -33,9 +33,9 @@ pub struct KakarotRpcModuleBuilder<P: Provider + Send + Sync + 'static> {
 impl<P: Provider + Send + Sync + 'static> KakarotRpcModuleBuilder<P> {
     pub fn new(kakarot_client: Arc<KakarotClient<P>>) -> Self {
         let eth_rpc_module = KakarotEthRpc::new(kakarot_client.clone()).into_rpc();
-        let alchemy_rpc_module = AlchemyRpc::new(kakarot_client).into_rpc();
+        let alchemy_rpc_module = AlchemyRpc::new(kakarot_client.clone()).into_rpc();
         let web3_rpc_module = Web3Rpc::default().into_rpc();
-        let net_rpc_module = NetRpc::default().into_rpc();
+        let net_rpc_module = NetRpc::new(kakarot_client.clone()).into_rpc();
 
         let mut modules: HashMap<KakarotRpcModule, Methods> = HashMap::new();
 
diff --git a/crates/eth-rpc/src/servers/net_rpc.rs b/crates/eth-rpc/src/servers/net_rpc.rs
index 9202dff6a..28cfe6826 100644
--- a/crates/eth-rpc/src/servers/net_rpc.rs
+++ b/crates/eth-rpc/src/servers/net_rpc.rs
@@ -1,22 +1,28 @@
 use jsonrpsee::core::{async_trait, RpcResult as Result};
 use kakarot_rpc_core::client::constants::CHAIN_ID;
+use kakarot_rpc_core::client::errors::EthApiError;
+use kakarot_rpc_core::client::KakarotClient;
 use reth_primitives::U64;
 use reth_rpc_types::PeerCount;
 
+use starknet::providers::Provider;
+use std::sync::Arc;
+
 use crate::api::net_api::NetApiServer;
 
 /// The RPC module for the implementing Net api
-#[derive(Default)]
-pub struct NetRpc {}
+pub struct NetRpc<P: Provider + Send + Sync + 'static> {
+    pub kakarot_client: Arc<KakarotClient<P>>,
+}
 
-impl NetRpc {
-    pub const fn new() -> Self {
-        Self {}
+impl<P: Provider + Send + Sync> NetRpc<P> {
+    pub fn new(kakarot_client: Arc<KakarotClient<P>>) -> Self {
+        Self { kakarot_client }
     }
 }
 
 #[async_trait]
-impl NetApiServer for NetRpc {
+impl<P: Provider + Send + Sync + 'static> NetApiServer for NetRpc<P> {
     fn version(&self) -> Result<U64> {
         Ok(CHAIN_ID.into())
     }
@@ -30,4 +36,11 @@ impl NetApiServer for NetRpc {
         // Kakarot RPC currently does not support peer-to-peer connections
         Ok(false)
     }
+
+    async fn health(&self) -> Result<bool> {
+        // Calls starknet block_number method to check if it resolves
+        self.kakarot_client.starknet_provider().block_number().await.map_err(EthApiError::from)?;
+
+        Ok(true)
+    }
 }
diff --git a/crates/eth-rpc/tests/integration.rs b/crates/eth-rpc/tests/integration.rs
index bf9964f29..6cfcae7b1 100644
--- a/crates/eth-rpc/tests/integration.rs
+++ b/crates/eth-rpc/tests/integration.rs
@@ -32,6 +32,14 @@ mod integration_tests {
     async fn test_erc20(#[future] katana: Katana) {
         let (server_addr, server_handle) =
             start_kakarot_rpc_server(&katana).await.expect("Error setting up Kakarot RPC server");
+
+        let reqwest_client = reqwest::Client::new();
+        let _res = reqwest_client
+            .post(format!("http://localhost:{}/net_health", server_addr.port()))
+            .send()
+            .await
+            .expect("net_health: health check failed");
+
         let wallet: LocalWallet = SigningKey::from_slice(katana.eoa().private_key().as_ref())
             .expect("EOA Private Key should be used to init a LocalWallet")
             .into();