From 30d40e9a32b6fde5159408d4d60fd2875bed348e Mon Sep 17 00:00:00 2001
From: Michael Vines <mvines@gmail.com>
Date: Fri, 17 Jan 2020 21:32:18 -0700
Subject: [PATCH] If a bad RPC node is selected try another one instead of
 aborting

---
 validator/src/main.rs | 47 +++++++++++++++++++++++++------------------
 1 file changed, 27 insertions(+), 20 deletions(-)

diff --git a/validator/src/main.rs b/validator/src/main.rs
index 61329fe14..499823708 100644
--- a/validator/src/main.rs
+++ b/validator/src/main.rs
@@ -197,7 +197,7 @@ fn get_rpc_addr(
     node: &Node,
     identity_keypair: &Arc<Keypair>,
     entrypoint_gossip: &SocketAddr,
-) -> (Pubkey, SocketAddr) {
+) -> (RpcClient, SocketAddr) {
     let mut cluster_info = ClusterInfo::new(node.info.clone(), identity_keypair.clone());
     cluster_info.set_entrypoint(ContactInfo::new_gossip_entry_point(entrypoint_gossip));
     let cluster_info = Arc::new(RwLock::new(cluster_info));
@@ -211,7 +211,7 @@ fn get_rpc_addr(
         &exit,
     );
 
-    let (id, rpc_addr) = loop {
+    let (rpc_client, rpc_addr) = loop {
         info!(
             "Searching for RPC service...\n{}",
             cluster_info.read().unwrap().contact_info_trace()
@@ -227,16 +227,30 @@ fn get_rpc_addr(
             .any(|contact_info| contact_info.gossip == *entrypoint_gossip);
 
         if found_entrypoint & !rpc_peers.is_empty() {
-            // Prefer the entrypoint's RPC service if present, otherwise pick a node at random
-            if let Some(contact_info) = rpc_peers
-                .iter()
-                .find(|contact_info| contact_info.gossip == *entrypoint_gossip)
-            {
-                break (contact_info.id, contact_info.rpc);
-            }
+            let (id, rpc_addr) = {
+                // Prefer the entrypoint's RPC service if present, otherwise pick a node at random
+                if let Some(contact_info) = rpc_peers
+                    .iter()
+                    .find(|contact_info| contact_info.gossip == *entrypoint_gossip)
+                {
+                    (contact_info.id, contact_info.rpc)
+                } else {
+                    let i = thread_rng().gen_range(0, rpc_peers.len());
+                    (rpc_peers[i].id, rpc_peers[i].rpc)
+                }
+            };
 
-            let i = thread_rng().gen_range(0, rpc_peers.len());
-            break (rpc_peers[i].id, rpc_peers[i].rpc);
+            info!("Contacting RPC port of node {}: {:?}", id, rpc_addr);
+            let rpc_client = RpcClient::new_socket(rpc_addr);
+            match rpc_client.get_version() {
+                Ok(rpc_version) => {
+                    info!("RPC node version: {}", rpc_version.solana_core);
+                    break (rpc_client, rpc_addr);
+                }
+                Err(err) => {
+                    warn!("Failed to get RPC version: {}", err);
+                }
+            }
         }
 
         sleep(Duration::from_secs(1));
@@ -245,7 +259,7 @@ fn get_rpc_addr(
     exit.store(true, Ordering::Relaxed);
     gossip_service.join().unwrap();
 
-    (id, rpc_addr)
+    (rpc_client, rpc_addr)
 }
 
 fn check_vote_account(
@@ -807,15 +821,8 @@ pub fn main() {
         );
 
         if !no_genesis_fetch {
-            let (rpc_node_id, rpc_addr) =
+            let (rpc_client, rpc_addr) =
                 get_rpc_addr(&node, &identity_keypair, &cluster_entrypoint.gossip);
-            info!("Using RPC from node {}: {:?}", rpc_node_id, rpc_addr);
-            let rpc_client = RpcClient::new_socket(rpc_addr);
-            let rpc_version = rpc_client.get_version().unwrap_or_else(|err| {
-                error!("Failed to get version: {}", err);
-                exit(1);
-            });
-            info!("RPC node version: {}", rpc_version.solana_core);
 
             download_ledger(&rpc_addr, &ledger_path, no_snapshot_fetch).unwrap_or_else(|err| {
                 error!("Failed to initialize ledger: {}", err);