client/: get_transaction_count() now returns a Result

bench-tps/src/bench.rs

@@ -54,14 +54,14 @@ pub fn sample_tx_count(
 ) {
     let client = create_client(v.client_facing_addr(), FULLNODE_PORT_RANGE);
     let mut now = Instant::now();
-    let mut initial_tx_count = client.transaction_count();
+    let mut initial_tx_count = client.get_transaction_count().expect("transaction count");
     let mut max_tps = 0.0;
     let mut total;
 
     let log_prefix = format!("{:21}:", v.tpu.to_string());
 
     loop {
-        let tx_count = client.transaction_count();
+        let tx_count = client.get_transaction_count().expect("transaction count");
         assert!(
             tx_count >= initial_tx_count,
             "expected tx_count({}) >= initial_tx_count({})",

bench-tps/src/main.rs

@@ -106,7 +106,7 @@ fn main() {
     let mut blockhash = client.get_recent_blockhash();
     println!("Got last ID {:?}", blockhash);
 
-    let first_tx_count = client.transaction_count();
+    let first_tx_count = client.get_transaction_count().expect("transaction count");
     println!("Initial transaction count {}", first_tx_count);
 
     let exit_signal = Arc::new(AtomicBool::new(false));

client/src/rpc_client.rs

@@ -102,23 +102,28 @@ impl RpcClient {
 
     /// Request the transaction count.  If the response packet is dropped by the network,
     /// this method will try again 5 times.
-    pub fn transaction_count(&self) -> u64 {
-        debug!("transaction_count");
-        for _tries in 0..5 {
+    pub fn get_transaction_count(&self) -> Result<u64, Box<dyn error::Error>> {
+        debug!("get_transaction_count");
+
+        let mut num_retries = 5;
+        loop {
             let response = self.client.send(&RpcRequest::GetTransactionCount, None, 0);
 
             match response {
                 Ok(value) => {
                     debug!("transaction_count response: {:?}", value);
                     let transaction_count = value.as_u64().unwrap();
-                    return transaction_count;
+                    return Ok(transaction_count);
                 }
-                Err(error) => {
-                    debug!("transaction_count failed: {:?}", error);
+                Err(err) => {
+                    debug!("transaction_count failed: {:?}", err);
+                    num_retries -= 1;
+                    if num_retries == 0 {
+                        return Err(err);
+                    }
                 }
-            };
+            }
         }
-        0
     }
 
     /// Request the last Entry ID from the server without blocking.

client/src/thin_client.rs

@@ -15,7 +15,7 @@ use solana_sdk::signature::{Keypair, KeypairUtil, Signature};
 use solana_sdk::system_transaction::SystemTransaction;
 use solana_sdk::timing;
 use solana_sdk::transaction::Transaction;
-use std;
+use std::error;
 use std::io;
 use std::net::{SocketAddr, UdpSocket};
 use std::time::{Duration, Instant};
@@ -141,8 +141,8 @@ impl ThinClient {
         self.rpc_client.get_balance(pubkey)
     }
 
-    pub fn transaction_count(&self) -> u64 {
-        self.rpc_client.transaction_count()
+    pub fn get_transaction_count(&self) -> Result<u64, Box<dyn error::Error>> {
+        self.rpc_client.get_transaction_count()
     }
 
     pub fn try_get_recent_blockhash(&self, num_retries: u64) -> Option<Hash> {

tests/thin_client.rs

@@ -25,7 +25,7 @@ fn test_thin_client_basic() {
 
     let client = create_client(leader_data.client_facing_addr(), FULLNODE_PORT_RANGE);
 
-    let transaction_count = client.transaction_count();
+    let transaction_count = client.get_transaction_count().unwrap();
     assert_eq!(transaction_count, 0);
 
     let blockhash = client.get_recent_blockhash();
@@ -40,7 +40,7 @@ fn test_thin_client_basic() {
     let balance = client.get_balance(&bob_pubkey);
     assert_eq!(balance.unwrap(), 500);
 
-    let transaction_count = client.transaction_count();
+    let transaction_count = client.get_transaction_count().unwrap();
     assert_eq!(transaction_count, 1);
     server.close().unwrap();
     remove_dir_all(ledger_path).unwrap();
@@ -144,7 +144,7 @@ fn test_transaction_count() {
         transactions_socket,
         Duration::from_secs(2),
     );
-    assert_eq!(client.transaction_count(), 0);
+    client.get_transaction_count().unwrap_err();
 }
 
 #[test]