apollo_network_benchmark: moved peerID creation files

crates/apollo_network_benchmark/Cargo.toml

@@ -10,6 +10,7 @@ description = "Benchmarking tool for the Apollo Network"
 testing = []
 
 [dependencies]
+anyhow.workspace = true
 apollo_metrics.workspace = true
 apollo_network.workspace = true
 clap = { workspace = true, features = ["derive", "env"] }

crates/apollo_network_benchmark/src/bin/apollo_network_benchmark_node/stress_test_node.rs

@@ -31,7 +31,8 @@ pub struct BroadcastNetworkStressTestNode {
 impl BroadcastNetworkStressTestNode {
     /// Creates network configuration from arguments
     fn create_network_config(args: &NodeArgs) -> NetworkConfig {
-        let peer_private_key = create_peer_private_key(args.runner.id);
+        let peer_private_key =
+            apollo_network_benchmark::peer_key::private_key_from_node_id(args.runner.id);
 
         let mut network_config = NetworkConfig {
             port: args.runner.p2p_port,
@@ -236,17 +237,3 @@ pub async fn race_and_kill_tasks(spawned_tasks: Vec<JoinHandle<()>>) {
         task.abort();
     }
 }
-
-fn create_peer_private_key(peer_index: u64) -> [u8; 32] {
-    let array = peer_index.to_le_bytes();
-    assert_eq!(array.len(), 8);
-    let mut private_key = [0u8; 32];
-    private_key[0..8].copy_from_slice(&array);
-
-    // Log the secret key
-    let peer_private_key_hex =
-        private_key.iter().map(|byte| format!("{byte:02x}")).collect::<String>();
-    info!("Secret Key: {peer_private_key_hex:#?}");
-
-    private_key
-}

crates/apollo_network_benchmark/src/lib.rs

@@ -1,2 +1,3 @@
 pub mod metrics;
 pub mod node_args;
+pub mod peer_key;

crates/apollo_network_benchmark/src/peer_key.rs

@@ -0,0 +1,18 @@
+use anyhow::Context;
+use libp2p::identity::Keypair;
+
+/// Derives a deterministic ed25519 private key from a node index.
+/// The index is written as little-endian bytes into the first 8 bytes of a 32-byte seed.
+pub fn private_key_from_node_id(node_id: u64) -> [u8; 32] {
+    let mut key = [0u8; 32];
+    key[..8].copy_from_slice(&node_id.to_le_bytes());
+    key
+}
+
+/// Returns the PeerId string for a given node index.
+pub fn peer_id_from_node_id(node_id: u64) -> anyhow::Result<String> {
+    let secret_key_bytes = private_key_from_node_id(node_id);
+    let keypair = Keypair::ed25519_from_bytes(secret_key_bytes)
+        .context("Failed to derive keypair from node id")?;
+    Ok(keypair.public().to_peer_id().to_string())
+}