From 60206c6b2beb93d89980145fbe215c8a706110a5 Mon Sep 17 00:00:00 2001
From: Paul Hauner <paul@paulhauner.com>
Date: Tue, 11 Jul 2023 15:04:56 +1000
Subject: [PATCH] Add flag to enable/disable BP in HTTP API

---
 beacon_node/http_api/src/lib.rs        |  7 ++++++-
 beacon_node/http_api/src/test_utils.rs |  1 +
 beacon_node/src/cli.rs                 | 10 ++++++++++
 beacon_node/src/config.rs              |  4 ++++
 lighthouse/tests/beacon_node.rs        | 16 ++++++++++++++++
 5 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/beacon_node/http_api/src/lib.rs b/beacon_node/http_api/src/lib.rs
index c3ca7c3d3a6..4cc9408d4bf 100644
--- a/beacon_node/http_api/src/lib.rs
+++ b/beacon_node/http_api/src/lib.rs
@@ -126,6 +126,7 @@ pub struct Config {
     pub allow_sync_stalled: bool,
     pub spec_fork_name: Option<ForkName>,
     pub data_dir: PathBuf,
+    pub enable_beacon_processor: bool,
 }
 
 impl Default for Config {
@@ -139,6 +140,7 @@ impl Default for Config {
             allow_sync_stalled: false,
             spec_fork_name: None,
             data_dir: PathBuf::from(DEFAULT_ROOT_DIR),
+            enable_beacon_processor: true,
         }
     }
 }
@@ -488,7 +490,10 @@ pub fn serve<T: BeaconChainTypes>(
     let app_start_filter = warp::any().map(move || app_start);
 
     // Create a `warp` filter that provides access the `TaskSpawner`.
-    let beacon_processor_send = ctx.beacon_processor_send.clone();
+    let beacon_processor_send = ctx
+        .beacon_processor_send
+        .clone()
+        .filter(|_| config.enable_beacon_processor);
     let task_spawner_filter =
         warp::any().map(move || TaskSpawner::new(beacon_processor_send.clone()));
 
diff --git a/beacon_node/http_api/src/test_utils.rs b/beacon_node/http_api/src/test_utils.rs
index aa6b0311753..28dc5a403c9 100644
--- a/beacon_node/http_api/src/test_utils.rs
+++ b/beacon_node/http_api/src/test_utils.rs
@@ -220,6 +220,7 @@ pub async fn create_api_server_on_port<T: BeaconChainTypes>(
             allow_sync_stalled: false,
             data_dir: std::path::PathBuf::from(DEFAULT_ROOT_DIR),
             spec_fork_name: None,
+            enable_beacon_processor: true,
         },
         chain: Some(chain),
         network_senders: Some(network_senders),
diff --git a/beacon_node/src/cli.rs b/beacon_node/src/cli.rs
index 32d49a680d8..26c1661f715 100644
--- a/beacon_node/src/cli.rs
+++ b/beacon_node/src/cli.rs
@@ -382,6 +382,16 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                     stalled. This is useful for very small testnets. TESTING ONLY. DO NOT USE ON \
                     MAINNET.")
         )
+        .arg(
+            Arg::with_name("http-enable-beacon-processor")
+                .long("http-enable-beacon-processor")
+                .help("The beacon processor is a scheduler which provides quality-of-service and \
+                    DoS protection. When set to \"true\", HTTP API requests will queued and scheduled \
+                    alongside other tasks. When set to \"false\", HTTP API responses will be executed \
+                    immediately.")
+                .takes_value(true)
+                .default_value("true")
+        )
         /* Prometheus metrics HTTP server related arguments */
         .arg(
             Arg::with_name("metrics")
diff --git a/beacon_node/src/config.rs b/beacon_node/src/config.rs
index bdae325805f..bc5c4010b48 100644
--- a/beacon_node/src/config.rs
+++ b/beacon_node/src/config.rs
@@ -4,6 +4,7 @@ use beacon_chain::chain_config::{
 };
 use clap::ArgMatches;
 use clap_utils::flags::DISABLE_MALLOC_TUNING_FLAG;
+use clap_utils::parse_required;
 use client::{ClientConfig, ClientGenesis};
 use directory::{DEFAULT_BEACON_NODE_DIR, DEFAULT_NETWORK_DIR, DEFAULT_ROOT_DIR};
 use environment::RuntimeContext;
@@ -148,6 +149,9 @@ pub fn get_config<E: EthSpec>(
         client_config.http_api.allow_sync_stalled = true;
     }
 
+    client_config.http_api.enable_beacon_processor =
+        parse_required(cli_args, "http-enable-beacon-processor")?;
+
     if let Some(cache_size) = clap_utils::parse_optional(cli_args, "shuffling-cache-size")? {
         client_config.chain.shuffling_cache_size = cache_size;
     }
diff --git a/lighthouse/tests/beacon_node.rs b/lighthouse/tests/beacon_node.rs
index a4c70e0a583..e4236385289 100644
--- a/lighthouse/tests/beacon_node.rs
+++ b/lighthouse/tests/beacon_node.rs
@@ -1464,6 +1464,22 @@ fn http_allow_sync_stalled_flag() {
         .with_config(|config| assert_eq!(config.http_api.allow_sync_stalled, true));
 }
 #[test]
+fn http_enable_beacon_processor() {
+    CommandLineTest::new()
+        .run_with_zero_port()
+        .with_config(|config| assert_eq!(config.http_api.enable_beacon_processor, true));
+
+    CommandLineTest::new()
+        .flag("http-enable-beacon-processor", Some("true"))
+        .run_with_zero_port()
+        .with_config(|config| assert_eq!(config.http_api.enable_beacon_processor, true));
+
+    CommandLineTest::new()
+        .flag("http-enable-beacon-processor", Some("false"))
+        .run_with_zero_port()
+        .with_config(|config| assert_eq!(config.http_api.enable_beacon_processor, false));
+}
+#[test]
 fn http_tls_flags() {
     let dir = TempDir::new().expect("Unable to create temporary directory");
     CommandLineTest::new()