Add beacon_chain_sim

tests/beacon_chain_sim/src/main.rs

@@ -0,0 +1,77 @@
+use node_test_rig::{
+    environment::{EnvironmentBuilder, RuntimeContext},
+    testing_client_config, ClientConfig, LocalBeaconNode, ProductionClient,
+};
+use types::EthSpec;
+
+pub type BeaconNode<E> = LocalBeaconNode<ProductionClient<E>>;
+
+fn main() {
+    match simulation(4) {
+        Ok(()) => println!("Simulation exited successfully"),
+        Err(e) => println!("Simulation exited with error: {}", e),
+    }
+}
+
+fn simulation(num_nodes: usize) -> Result<(), String> {
+    if num_nodes < 1 {
+        return Err("Must have at least one node".into());
+    }
+
+    let mut env = EnvironmentBuilder::minimal()
+        .async_logger("debug")?
+        .multi_threaded_tokio_runtime()?
+        .build()?;
+
+    let base_config = testing_client_config();
+
+    let boot_node =
+        BeaconNode::production(env.service_context("boot_node".into()), base_config.clone());
+
+    let nodes = (1..num_nodes)
+        .map(|i| {
+            let context = env.service_context(format!("node_{}", i));
+            new_with_bootnode_via_enr(context, &boot_node, base_config.clone())
+        })
+        .collect::<Vec<_>>();
+
+    env.block_until_ctrl_c()?;
+
+    Ok(())
+}
+
+// TODO: this function does not result in nodes connecting to each other. Age to investigate?
+fn new_with_bootnode_via_enr<E: EthSpec>(
+    context: RuntimeContext<E>,
+    boot_node: &BeaconNode<E>,
+    base_config: ClientConfig,
+) -> BeaconNode<E> {
+    let mut config = base_config;
+    config.network.boot_nodes.push(
+        boot_node
+            .client
+            .enr()
+            .expect("bootnode must have a network"),
+    );
+
+    BeaconNode::production(context, config)
+}
+
+fn new_with_bootnode_via_multiaddr<E: EthSpec>(
+    context: RuntimeContext<E>,
+    boot_node: &BeaconNode<E>,
+    base_config: ClientConfig,
+) -> BeaconNode<E> {
+    let mut config = base_config;
+    config.network.libp2p_nodes.push(
+        boot_node
+            .client
+            .libp2p_listen_addresses()
+            .expect("bootnode must have a network")
+            .first()
+            .expect("bootnode must have at least one listen addr")
+            .clone(),
+    );
+
+    BeaconNode::production(context, config)
+}