Pull Eth2Config during bootstrap

beacon_node/beacon_chain/Cargo.toml

@@ -5,6 +5,7 @@ authors = ["Paul Hauner <paul@paulhauner.com>", "Age Manning <Age@AgeManning.com
 edition = "2018"
 
 [dependencies]
+eth2_config = { path = "../../eth2/utils/eth2_config" }
 store = { path = "../store" }
 parking_lot = "0.7"
 lazy_static = "1.3.0"

beacon_node/beacon_chain/src/bootstrapper.rs

@@ -1,3 +1,4 @@
+use eth2_config::Eth2Config;
 use eth2_libp2p::{
     multiaddr::{Multiaddr, Protocol},
     Enr,
@@ -74,6 +75,11 @@ impl Bootstrapper {
         }
     }
 
+    /// Returns the servers Eth2Config.
+    pub fn eth2_config(&self) -> Result<Eth2Config, String> {
+        get_eth2_config(self.url.clone()).map_err(|e| format!("Unable to get Eth2Config: {:?}", e))
+    }
+
     /// Returns the servers ENR address.
     pub fn enr(&self) -> Result<Enr, String> {
         get_enr(self.url.clone()).map_err(|e| format!("Unable to get ENR: {:?}", e))
@@ -129,6 +135,19 @@ fn get_slots_per_epoch(mut url: Url) -> Result<Slot, Error> {
         .map_err(Into::into)
 }
 
+fn get_eth2_config(mut url: Url) -> Result<Eth2Config, Error> {
+    url.path_segments_mut()
+        .map(|mut url| {
+            url.push("spec").push("eth2_config");
+        })
+        .map_err(|_| Error::InvalidUrl)?;
+
+    reqwest::get(url)?
+        .error_for_status()?
+        .json()
+        .map_err(Into::into)
+}
+
 fn get_finalized_slot(mut url: Url, slots_per_epoch: u64) -> Result<Slot, Error> {
     url.path_segments_mut()
         .map(|mut url| {

beacon_node/client/src/lib.rs

@@ -162,6 +162,7 @@ where
                 beacon_chain.clone(),
                 network.clone(),
                 client_config.db_path().expect("unable to read datadir"),
+                eth2_config.clone(),
                 &log,
             ) {
                 Ok(s) => Some(s),

beacon_node/rest_api/Cargo.toml

@@ -27,5 +27,6 @@ exit-future = "0.1.3"
 tokio = "0.1.17"
 url = "2.0"
 lazy_static = "1.3.0"
+eth2_config = { path = "../../eth2/utils/eth2_config" }
 lighthouse_metrics = { path = "../../eth2/utils/lighthouse_metrics" }
 slot_clock = { path = "../../eth2/utils/slot_clock" }

beacon_node/rest_api/src/lib.rs

@@ -13,6 +13,7 @@ mod url_query;
 
 use beacon_chain::{BeaconChain, BeaconChainTypes};
 use client_network::Service as NetworkService;
+use eth2_config::Eth2Config;
 use hyper::rt::Future;
 use hyper::service::service_fn_ok;
 use hyper::{Body, Method, Response, Server, StatusCode};
@@ -79,6 +80,7 @@ pub fn start_server<T: BeaconChainTypes>(
     beacon_chain: Arc<BeaconChain<T>>,
     network_service: Arc<NetworkService<T>>,
     db_path: PathBuf,
+    eth2_config: Eth2Config,
     log: &slog::Logger,
 ) -> Result<exit_future::Signal, hyper::Error> {
     let log = log.new(o!("Service" => "Api"));
@@ -100,12 +102,14 @@ pub fn start_server<T: BeaconChainTypes>(
     // Clone our stateful objects, for use in service closure.
     let server_log = log.clone();
     let server_bc = beacon_chain.clone();
+    let eth2_config = Arc::new(eth2_config);
 
     let service = move || {
         let log = server_log.clone();
         let beacon_chain = server_bc.clone();
         let db_path = db_path.clone();
         let network_service = network_service.clone();
+        let eth2_config = eth2_config.clone();
 
         // Create a simple handler for the router, inject our stateful objects into the request.
         service_fn_ok(move |mut req| {
@@ -118,6 +122,8 @@ pub fn start_server<T: BeaconChainTypes>(
             req.extensions_mut().insert::<DBPath>(db_path.clone());
             req.extensions_mut()
                 .insert::<Arc<NetworkService<T>>>(network_service.clone());
+            req.extensions_mut()
+                .insert::<Arc<Eth2Config>>(eth2_config.clone());
 
             let path = req.uri().path().to_string();
 
@@ -144,6 +150,7 @@ pub fn start_server<T: BeaconChainTypes>(
                 (&Method::GET, "/node/genesis_time") => node::get_genesis_time::<T>(req),
                 (&Method::GET, "/spec") => spec::get_spec::<T>(req),
                 (&Method::GET, "/spec/slots_per_epoch") => spec::get_slots_per_epoch::<T>(req),
+                (&Method::GET, "/spec/eth2_config") => spec::get_eth2_config::<T>(req),
                 _ => Err(ApiError::MethodNotAllowed(path.clone())),
             };
 

beacon_node/rest_api/src/spec.rs

@@ -1,6 +1,7 @@
 use super::{success_response, ApiResult};
 use crate::ApiError;
 use beacon_chain::{BeaconChain, BeaconChainTypes};
+use eth2_config::Eth2Config;
 use hyper::{Body, Request};
 use std::sync::Arc;
 use types::EthSpec;
@@ -18,6 +19,19 @@ pub fn get_spec<T: BeaconChainTypes + 'static>(req: Request<Body>) -> ApiResult
     Ok(success_response(Body::from(json)))
 }
 
+/// HTTP handler to return the full Eth2Config object.
+pub fn get_eth2_config<T: BeaconChainTypes + 'static>(req: Request<Body>) -> ApiResult {
+    let eth2_config = req
+        .extensions()
+        .get::<Arc<Eth2Config>>()
+        .ok_or_else(|| ApiError::ServerError("Eth2Config extension missing".to_string()))?;
+
+    let json: String = serde_json::to_string(eth2_config.as_ref())
+        .map_err(|e| ApiError::ServerError(format!("Unable to serialize Eth2Config: {:?}", e)))?;
+
+    Ok(success_response(Body::from(json)))
+}
+
 /// HTTP handler to return the full spec object.
 pub fn get_slots_per_epoch<T: BeaconChainTypes + 'static>(_req: Request<Body>) -> ApiResult {
     let json: String = serde_json::to_string(&T::EthSpec::slots_per_epoch())

beacon_node/src/config.rs

@@ -63,7 +63,13 @@ fn process_testnet_subcommand(
         builder.set_random_datadir()?;
     }
 
+    let is_bootstrap = cli_args.subcommand_name() == Some("bootstrap");
+
     if let Some(path_string) = cli_args.value_of("eth2-config") {
+        if is_bootstrap {
+            return Err("Cannot supply --eth2-config when using bootsrap".to_string());
+        }
+
         let path = path_string
             .parse::<PathBuf>()
             .map_err(|e| format!("Unable to parse eth2-config path: {:?}", e))?;
@@ -100,6 +106,7 @@ fn process_testnet_subcommand(
                 .and_then(|s| s.parse::<u16>().ok());
 
             builder.import_bootstrap_libp2p_address(server, port)?;
+            builder.import_bootstrap_eth2_config(server)?;
 
             builder.set_beacon_chain_start_method(BeaconChainStartMethod::HttpBootstrap {
                 server: server.to_string(),
@@ -252,6 +259,19 @@ impl<'a> ConfigBuilder<'a> {
         Ok(())
     }
 
+    /// Imports an `Eth2Config` from `server`, returning an error if this fails.
+    pub fn import_bootstrap_eth2_config(&mut self, server: &str) -> Result<()> {
+        let bootstrapper = Bootstrapper::from_server_string(server.to_string())?;
+
+        self.update_eth2_config(bootstrapper.eth2_config()?);
+
+        Ok(())
+    }
+
+    fn update_eth2_config(&mut self, eth2_config: Eth2Config) {
+        self.eth2_config = eth2_config;
+    }
+
     /// Reads the subcommand and tries to update `self.eth2_config` based up on the `--spec` flag.
     ///
     /// Returns an error if the `--spec` flag is not present in the given `cli_args`.