Network sync refactoring (part 3) (#11347)

* Move `light.v1.proto` schema into new crate `sc-network-light`

* Move `sc_network::light_client_requests` and submodule to `sc_network_light::light_client_requests`

* Fix apparently outdated reference in documentation and visibility modifier

* Fix rustdoc check

* Update lock file

substrate/Cargo.lock

@@ -8509,6 +8509,7 @@ dependencies = [
  "sc-client-api",
  "sc-consensus",
  "sc-network-common",
+ "sc-network-light",
  "sc-network-sync",
  "sc-peerset",
  "sc-utils",
@@ -8564,6 +8565,25 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "sc-network-light"
+version = "0.10.0-dev"
+dependencies = [
+ "futures",
+ "libp2p",
+ "log",
+ "parity-scale-codec",
+ "prost",
+ "prost-build",
+ "sc-client-api",
+ "sc-network-common",
+ "sc-peerset",
+ "sp-blockchain",
+ "sp-core",
+ "sp-runtime",
+ "thiserror",
+]
+
 [[package]]
 name = "sc-network-sync"
 version = "0.10.0-dev"

substrate/Cargo.toml

@@ -42,8 +42,9 @@ members = [
 	"client/informant",
 	"client/keystore",
 	"client/network",
-	"client/network/common",
 	"client/network-gossip",
+	"client/network/common",
+	"client/network/light",
 	"client/network/sync",
 	"client/network/test",
 	"client/offchain",

substrate/client/network/Cargo.toml

@@ -51,6 +51,7 @@ sc-block-builder = { version = "0.10.0-dev", path = "../block-builder" }
 sc-client-api = { version = "4.0.0-dev", path = "../api" }
 sc-consensus = { version = "0.10.0-dev", path = "../consensus/common" }
 sc-network-common = { version = "0.10.0-dev", path = "./common" }
+sc-network-light = { version = "0.10.0-dev", path = "./light" }
 sc-network-sync = { version = "0.10.0-dev", path = "./sync" }
 sc-peerset = { version = "4.0.0-dev", path = "../peerset" }
 sc-utils = { version = "4.0.0-dev", path = "../utils" }

substrate/client/network/build.rs

@@ -1,4 +1,4 @@
-const PROTOS: &[&str] = &["src/schema/light.v1.proto", "src/schema/bitswap.v1.2.0.proto"];
+const PROTOS: &[&str] = &["src/schema/bitswap.v1.2.0.proto"];
 
 fn main() {
 	prost_build::compile_protos(PROTOS, &["src/schema"]).unwrap();

substrate/client/network/light/Cargo.toml

@@ -0,0 +1,33 @@
+[package]
+description = "Substrate light network protocol"
+name = "sc-network-light"
+version = "0.10.0-dev"
+license = "GPL-3.0-or-later WITH Classpath-exception-2.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2021"
+homepage = "https://substrate.io"
+repository = "https://github.com/paritytech/substrate/"
+documentation = "https://docs.rs/sc-network-light"
+readme = "README.md"
+
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
+
+[build-dependencies]
+prost-build = "0.9"
+
+[dependencies]
+codec = { package = "parity-scale-codec", version = "3.0.0", features = [
+    "derive",
+] }
+futures = "0.3.21"
+libp2p = "0.44.0"
+log = "0.4.16"
+prost = "0.9"
+sp-blockchain = { version = "4.0.0-dev", path = "../../../primitives/blockchain" }
+sc-client-api = { version = "4.0.0-dev", path = "../../api" }
+sc-network-common = { version = "0.10.0-dev", path = "../common" }
+sc-peerset = { version = "4.0.0-dev", path = "../../peerset" }
+sp-core = { version = "6.0.0", path = "../../../primitives/core" }
+sp-runtime = { version = "6.0.0", path = "../../../primitives/runtime" }
+thiserror = "1.0"

substrate/client/network/light/build.rs

@@ -0,0 +1,5 @@
+const PROTOS: &[&str] = &["src/schema/light.v1.proto"];
+
+fn main() {
+	prost_build::compile_protos(PROTOS, &["src/schema"]).unwrap();
+}

substrate/client/network/light/src/lib.rs

@@ -0,0 +1,22 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2017-2022 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! Light client data structures of the networking layer.
+
+pub mod light_client_requests;
+mod schema;

substrate/client/network/light/src/light_client_requests/handler.rs

@@ -22,9 +22,10 @@
 //! `crate::request_responses::RequestResponsesBehaviour` with
 //! [`LightClientRequestHandler`](handler::LightClientRequestHandler).
 
-use crate::{schema, PeerId};
+use crate::schema;
 use codec::{self, Decode, Encode};
 use futures::{channel::mpsc, prelude::*};
+use libp2p::PeerId;
 use log::{debug, trace};
 use prost::Message;
 use sc_client_api::{ProofProvider, StorageProof};
@@ -55,7 +56,7 @@ where
 	B: Block,
 	Client: ProofProvider<B> + Send + Sync + 'static,
 {
-	/// Create a new [`sc_network_sync::block_request_handler::BlockRequestHandler`].
+	/// Create a new [`LightClientRequestHandler`].
 	pub fn new(protocol_id: &ProtocolId, client: Arc<Client>) -> (Self, ProtocolConfig) {
 		// For now due to lack of data on light client request handling in production systems, this
 		// value is chosen to match the block request limit.

substrate/client/network/light/src/schema.rs

@@ -0,0 +1,25 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2017-2022 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! Include sources generated from protobuf definitions.
+
+pub(crate) mod v1 {
+	pub(crate) mod light {
+		include!(concat!(env!("OUT_DIR"), "/api.v1.light.rs"));
+	}
+}

substrate/client/network/src/config.rs

@@ -122,10 +122,10 @@ where
 	/// Request response configuration for the light client request protocol.
 	///
 	/// Can be constructed either via
-	/// [`crate::light_client_requests::generate_protocol_config`] allowing outgoing but not
-	/// incoming requests, or constructed via
-	/// [`crate::light_client_requests::handler::LightClientRequestHandler::new`] allowing
-	/// both outgoing and incoming requests.
+	/// [`sc_network_light::light_client_requests::generate_protocol_config`] allowing outgoing but
+	/// not incoming requests, or constructed via
+	/// [`sc_network_light::light_client_requests::handler::LightClientRequestHandler::new`]
+	/// allowing both outgoing and incoming requests.
 	pub light_client_request_protocol_config: RequestResponseConfig,
 
 	/// Request response configuration for the state request protocol.

substrate/client/network/src/lib.rs

@@ -257,7 +257,6 @@ mod utils;
 pub mod bitswap;
 pub mod config;
 pub mod error;
-pub mod light_client_requests;
 pub mod network_state;
 pub mod transactions;
 
@@ -267,6 +266,7 @@ pub use protocol::{
 	event::{DhtEvent, Event, ObservedRole},
 	PeerInfo,
 };
+pub use sc_network_light::light_client_requests;
 pub use sc_network_sync::{
 	block_request_handler,
 	state::StateDownloadProgress,

substrate/client/network/src/schema.rs

@@ -18,12 +18,6 @@
 
 //! Include sources generated from protobuf definitions.
 
-pub mod v1 {
-	pub mod light {
-		include!(concat!(env!("OUT_DIR"), "/api.v1.light.rs"));
-	}
-}
-
 pub mod bitswap {
 	include!(concat!(env!("OUT_DIR"), "/bitswap.message.rs"));
 }

substrate/client/network/src/service/tests.rs

@@ -17,13 +17,13 @@
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
 use crate::{
-	config, light_client_requests::handler::LightClientRequestHandler,
-	state_request_handler::StateRequestHandler, Event, NetworkService, NetworkWorker,
+	config, state_request_handler::StateRequestHandler, Event, NetworkService, NetworkWorker,
 };
 
 use futures::prelude::*;
 use libp2p::PeerId;
 use sc_network_common::config::ProtocolId;
+use sc_network_light::light_client_requests::handler::LightClientRequestHandler;
 use sc_network_sync::block_request_handler::BlockRequestHandler;
 use sp_runtime::traits::{Block as BlockT, Header as _};
 use std::{borrow::Cow, sync::Arc, time::Duration};

substrate/client/network/sync/src/block_request_handler.rs

@@ -75,9 +75,7 @@ pub fn generate_protocol_config(protocol_id: &ProtocolId) -> ProtocolConfig {
 }
 
 /// Generate the block protocol name from chain specific protocol identifier.
-// Visibility `pub(crate)` to allow `crate::light_client_requests::sender` to generate block request
-// protocol name and send block requests.
-pub(crate) fn generate_protocol_name(protocol_id: &ProtocolId) -> String {
+fn generate_protocol_name(protocol_id: &ProtocolId) -> String {
 	format!("/{}/sync/2", protocol_id.as_ref())
 }