Cli: expose last-valid-slot in solana fees

cli/src/cli.rs

@@ -1655,7 +1655,7 @@ pub fn process_command(config: &CliConfig) -> ProcessResult {
             seed,
             program_id,
         } => process_create_address_with_seed(config, from_pubkey.as_ref(), &seed, &program_id),
-        CliCommand::Fees => process_fees(&rpc_client),
+        CliCommand::Fees => process_fees(&rpc_client, config),
         CliCommand::GetBlockTime { slot } => process_get_block_time(&rpc_client, config, *slot),
         CliCommand::GetGenesisHash => process_get_genesis_hash(&rpc_client),
         CliCommand::GetEpochInfo { commitment_config } => {

cli/src/cli_output.rs

@@ -900,6 +900,7 @@ impl fmt::Display for CliSignOnlyData {
 }
 
 #[derive(Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
 pub struct CliSignature {
     pub signature: String,
 }
@@ -913,6 +914,7 @@ impl fmt::Display for CliSignature {
 }
 
 #[derive(Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
 pub struct CliAccountBalances {
     pub accounts: Vec<RpcAccountBalance>,
 }
@@ -937,6 +939,7 @@ impl fmt::Display for CliAccountBalances {
 }
 
 #[derive(Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
 pub struct CliSupply {
     pub total: u64,
     pub circulating: u64,
@@ -981,3 +984,25 @@ impl fmt::Display for CliSupply {
         Ok(())
     }
 }
+
+#[derive(Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct CliFees {
+    pub slot: Slot,
+    pub blockhash: String,
+    pub lamports_per_signature: u64,
+    pub last_valid_slot: Slot,
+}
+
+impl fmt::Display for CliFees {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        writeln_name_value(f, "Blockhash:", &self.blockhash)?;
+        writeln_name_value(
+            f,
+            "Lamports per signature:",
+            &self.lamports_per_signature.to_string(),
+        )?;
+        writeln_name_value(f, "Last valid slot:", &self.last_valid_slot.to_string())?;
+        Ok(())
+    }
+}

cli/src/cluster_query.rs

@@ -597,13 +597,16 @@ pub fn process_cluster_version(rpc_client: &RpcClient) -> ProcessResult {
     Ok(remote_version.solana_core)
 }
 
-pub fn process_fees(rpc_client: &RpcClient) -> ProcessResult {
-    let (recent_blockhash, fee_calculator) = rpc_client.get_recent_blockhash()?;
-
-    Ok(format!(
-        "blockhash: {}\nlamports per signature: {}",
-        recent_blockhash, fee_calculator.lamports_per_signature
-    ))
+pub fn process_fees(rpc_client: &RpcClient, config: &CliConfig) -> ProcessResult {
+    let result = rpc_client.get_recent_blockhash_with_commitment(CommitmentConfig::default())?;
+    let (recent_blockhash, fee_calculator, last_valid_slot) = result.value;
+    let fees = CliFees {
+        slot: result.context.slot,
+        blockhash: recent_blockhash.to_string(),
+        lamports_per_signature: fee_calculator.lamports_per_signature,
+        last_valid_slot,
+    };
+    Ok(config.output_format.formatted_string(&fees))
 }
 
 pub fn process_leader_schedule(rpc_client: &RpcClient) -> ProcessResult {