CLI: Support retrieving past leader schedules (bp #14304) (#14311)

* clap-utils: Add epoch validator

(cherry picked from commit a709850ee4)

* CLI: Support displaying past leader schedules

(cherry picked from commit bd761e2a52)

Co-authored-by: Trent Nelson <trent@solana.com>

clap-utils/src/input_validators.rs

@@ -1,7 +1,7 @@
 use crate::keypair::{parse_keypair_path, KeypairUrl, ASK_KEYWORD};
 use chrono::DateTime;
 use solana_sdk::{
-    clock::Slot,
+    clock::{Epoch, Slot},
     hash::Hash,
     pubkey::Pubkey,
     signature::{read_keypair_file, Signature},
@@ -148,6 +148,13 @@ where
     }
 }
 
+pub fn is_epoch<T>(epoch: T) -> Result<(), String>
+where
+    T: AsRef<str> + Display,
+{
+    is_parsable_generic::<Epoch, _>(epoch)
+}
+
 pub fn is_slot<T>(slot: T) -> Result<(), String>
 where
     T: AsRef<str> + Display,

cli/src/cli.rs

@@ -118,7 +118,9 @@ pub enum CliCommand {
     LargestAccounts {
         filter: Option<RpcLargestAccountsFilter>,
     },
-    LeaderSchedule,
+    LeaderSchedule {
+        epoch: Option<Epoch>,
+    },
     LiveSlots,
     Logs {
         filter: RpcTransactionLogsFilter,
@@ -582,10 +584,7 @@ pub fn parse_command(
         ("supply", Some(matches)) => parse_supply(matches),
         ("total-supply", Some(matches)) => parse_total_supply(matches),
         ("transaction-count", Some(matches)) => parse_get_transaction_count(matches),
-        ("leader-schedule", Some(_matches)) => Ok(CliCommandInfo {
-            command: CliCommand::LeaderSchedule,
-            signers: vec![],
-        }),
+        ("leader-schedule", Some(matches)) => parse_leader_schedule(matches),
         ("ping", Some(matches)) => parse_cluster_ping(matches, default_signer, wallet_manager),
         ("live-slots", Some(_matches)) => Ok(CliCommandInfo {
             command: CliCommand::LiveSlots,
@@ -1562,7 +1561,7 @@ pub fn process_command(config: &CliConfig) -> ProcessResult {
         CliCommand::Inflation(inflation_subcommand) => {
             process_inflation_subcommand(&rpc_client, config, inflation_subcommand)
         }
-        CliCommand::LeaderSchedule => process_leader_schedule(&rpc_client),
+        CliCommand::LeaderSchedule { epoch } => process_leader_schedule(&rpc_client, *epoch),
         CliCommand::LiveSlots => process_live_slots(&config),
         CliCommand::Logs { filter } => process_logs(&config, filter),
         CliCommand::Ping {

cli/src/cluster_query.rs

@@ -132,7 +132,17 @@ impl ClusterQuerySubCommands for App<'_, '_> {
                     .help("Slot number of the block to query")
             )
         )
-        .subcommand(SubCommand::with_name("leader-schedule").about("Display leader schedule"))
+        .subcommand(SubCommand::with_name("leader-schedule")
+            .about("Display leader schedule")
+            .arg(
+                Arg::with_name("epoch")
+                    .long("epoch")
+                    .takes_value(true)
+                    .value_name("EPOCH")
+                    .validator(is_epoch)
+                    .help("Epoch to show leader schedule for. (default: current)")
+            )
+        )
         .subcommand(
             SubCommand::with_name("epoch-info")
             .about("Get information about the current epoch")
@@ -713,9 +723,23 @@ pub fn process_first_available_block(rpc_client: &RpcClient) -> ProcessResult {
     Ok(format!("{}", first_available_block))
 }
 
-pub fn process_leader_schedule(rpc_client: &RpcClient) -> ProcessResult {
+pub fn parse_leader_schedule(matches: &ArgMatches<'_>) -> Result<CliCommandInfo, CliError> {
+    let epoch = value_of(matches, "epoch");
+    Ok(CliCommandInfo {
+        command: CliCommand::LeaderSchedule { epoch },
+        signers: vec![],
+    })
+}
+
+pub fn process_leader_schedule(rpc_client: &RpcClient, epoch: Option<Epoch>) -> ProcessResult {
     let epoch_info = rpc_client.get_epoch_info()?;
-    let first_slot_in_epoch = epoch_info.absolute_slot - epoch_info.slot_index;
+    let epoch = epoch.unwrap_or(epoch_info.epoch);
+    if epoch > epoch_info.epoch {
+        return Err(format!("Epoch {} is in the future", epoch).into());
+    }
+
+    let epoch_schedule = rpc_client.get_epoch_schedule()?;
+    let first_slot_in_epoch = epoch_schedule.get_first_slot_in_epoch(epoch);
 
     let leader_schedule = rpc_client.get_leader_schedule(Some(first_slot_in_epoch))?;
     if leader_schedule.is_none() {