From 78c2a9ef52483fc56da129ef6f6a7562f418c546 Mon Sep 17 00:00:00 2001
From: Michael Vines <mvines@gmail.com>
Date: Fri, 22 Jan 2021 19:11:41 -0800
Subject: [PATCH] Fetch blockhash for each transaction simulation to avoid
 stale blockhashes

---
 stake-o-matic/src/main.rs | 13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/stake-o-matic/src/main.rs b/stake-o-matic/src/main.rs
index 58df7916aa..996b55a952 100644
--- a/stake-o-matic/src/main.rs
+++ b/stake-o-matic/src/main.rs
@@ -463,16 +463,11 @@ fn simulate_transactions(
     rpc_client: &RpcClient,
     candidate_transactions: Vec<(Transaction, String)>,
 ) -> client_error::Result<Vec<(Transaction, String)>> {
-    let (blockhash, _fee_calculator) = rpc_client.get_recent_blockhash()?;
-
-    info!(
-        "Simulating {} transactions with blockhash {}",
-        candidate_transactions.len(),
-        blockhash
-    );
+    info!("Simulating {} transactions", candidate_transactions.len(),);
     let mut simulated_transactions = vec![];
     for (mut transaction, memo) in candidate_transactions {
-        transaction.message.recent_blockhash = blockhash;
+        transaction.message.recent_blockhash =
+            retry_rpc_operation(10, || rpc_client.get_recent_blockhash())?.0;
 
         let sim_result = rpc_client.simulate_transaction_with_config(
             &transaction,
@@ -511,7 +506,7 @@ fn transact(
     );
 
     let (blockhash, fee_calculator, last_valid_slot) = rpc_client
-        .get_recent_blockhash_with_commitment(CommitmentConfig::max())?
+        .get_recent_blockhash_with_commitment(rpc_client.commitment())?
         .value;
     info!("{} transactions to send", transactions.len());