More clean up

node/cli/Cargo.toml

@@ -23,11 +23,8 @@ crate-type = ["cdylib", "rlib"]
 
 [dependencies]
 log = "0.4.8"
-tokio = { version = "0.1.22", optional = true }
 futures = "0.1.29"
-exit-future = { version = "0.1.4", optional = true }
 jsonrpc-core = "13.2.0"
-substrate-cli = { path = "../../core/cli", optional = true }
 codec = { package = "parity-scale-codec", version = "1.0.0" }
 sr-io = { path = "../../core/sr-io" }
 client = { package = "substrate-client", path = "../../core/client" }
@@ -51,7 +48,6 @@ sr-primitives = { path = "../../core/sr-primitives" }
 node-executor = { path = "../executor" }
 substrate-telemetry = { package = "substrate-telemetry", path = "../../core/telemetry" }
 structopt = "0.3.3"
-transaction-factory = { path = "../../test-utils/transaction-factory", optional = true }
 keyring = { package = "substrate-keyring", path = "../../core/keyring" }
 indices = { package = "srml-indices", path = "../../srml/indices" }
 timestamp = { package = "srml-timestamp", path = "../../srml/timestamp", default-features = false }
@@ -66,19 +62,24 @@ im_online = { package = "srml-im-online", path = "../../srml/im-online", default
 serde = { version = "1.0.101", features = [ "derive" ] }
 client_db = { package = "substrate-client-db", path = "../../core/client/db", default-features = false }
 offchain = { package = "substrate-offchain", path = "../../core/offchain" }
+
+# CLI-specific dependencies
+tokio = { version = "0.1.22", optional = true }
+exit-future = { version = "0.1.4", optional = true }
+substrate-cli = { path = "../../core/cli", optional = true }
+transaction-factory = { path = "../../test-utils/transaction-factory", optional = true }
 ctrlc = { version = "3.1.3", features = ["termination"], optional = true }
 
 # WASM-specific dependencies
 libp2p = { version = "0.12.0", default-features = false, optional = true }
-clear_on_drop = { version = "0.2.3", features = ["no_cc"], optional = true }
+clear_on_drop = { version = "0.2.3", features = ["no_cc"], optional = true }	# Imported just for the `no_cc` feature
 console_error_panic_hook = { version = "0.1.1", optional = true }
 console_log = { version = "0.1.2", optional = true }
 js-sys = { version = "0.3.22", optional = true }
 wasm-bindgen = { version = "0.2.45", optional = true }
 wasm-bindgen-futures = { version = "0.3.22", optional = true }
 kvdb-memorydb = { git = "https://github.com/paritytech/parity-common", rev="b0317f649ab2c665b7987b8475878fc4d2e1f81d", optional = true }
-# TODO: need the feature
-rand6 = { package = "rand", version = "0.6", features = ["wasm-bindgen"] }
+rand6 = { package = "rand", version = "0.6", features = ["wasm-bindgen"], optional = true }	# Imported just for the `wasm-bindgen` feature
 
 [dev-dependencies]
 keystore = { package = "substrate-keystore", path = "../../core/keystore" }
@@ -95,7 +96,23 @@ vergen = "3.0.4"
 
 [features]
 default = ["cli"]
-# TODO: docs
-browser = ["clear_on_drop", "console_error_panic_hook", "console_log", "js-sys", "libp2p", "wasm-bindgen", "wasm-bindgen-futures", "kvdb-memorydb", "rand/wasm-bindgen"]
-# TODO: docs
-cli = ["substrate-cli", "transaction-factory", "tokio", "exit-future", "ctrlc", "client_db/kvdb-rocksdb"]
+browser = [
+	"clear_on_drop",
+	"console_error_panic_hook",
+	"console_log",
+	"js-sys",
+	"libp2p",
+	"wasm-bindgen",
+	"wasm-bindgen-futures",
+	"kvdb-memorydb",
+	"rand/wasm-bindgen",
+	"rand6"
+]
+cli = [
+	"substrate-cli",
+	"transaction-factory",
+	"tokio",
+	"exit-future",
+	"ctrlc",
+	"client_db/kvdb-rocksdb"
+]

node/cli/browser-demo/README.md

@@ -3,7 +3,7 @@
 ```sh
 cargo install wasm-pack		# If necessary
 
-# From the `node-browser` directory (parent from this README)
+# From the `node/cli` directory (parent from this README)
 wasm-pack build --target web --out-dir ./demo/pkg --no-typescript --release -- --no-default-features --features "browser"
 
 xdg-open index.html

node/cli/src/browser.rs

@@ -25,6 +25,8 @@ use substrate_service::{AbstractService, RpcSession, Roles as ServiceRoles, Conf
 use wasm_bindgen::prelude::*;
 
 /// Starts the client.
+///
+/// You must pass a libp2p transport that supports .
 #[wasm_bindgen]
 pub fn start_client(wasm_ext: wasm_ext::ffi::Transport) -> Result<Client, JsValue> {
 	start_inner(wasm_ext)
@@ -35,35 +37,40 @@ fn start_inner(wasm_ext: wasm_ext::ffi::Transport) -> Result<Client, Box<dyn std
 	console_error_panic_hook::set_once();
 	console_log::init_with_level(log::Level::Info);
 
-	let wasm_ext = wasm_ext::ExtTransport::new(wasm_ext);
-
-	let chain_spec = ChainSpec::FlamingFir.load().map_err(|e| format!("{:?}", e))?;
-	let mut config = Configuration::<(), _, _>::default_with_spec(chain_spec);
-	config.network.transport = network::config::TransportConfig::Normal {
-		wasm_external_transport: Some(wasm_ext.clone()),
-		enable_mdns: false,
-	};
-	config.telemetry_external_transport = Some(wasm_ext);
-	config.roles = ServiceRoles::FULL;
-	config.name = "Browser node".to_string();
-	config.database = {
-		let db = Arc::new(kvdb_memorydb::create(10));
-		DatabaseConfig::Custom(db)
+	// Build the configuration to pass to the service.
+	let config = {
+		let wasm_ext = wasm_ext::ExtTransport::new(wasm_ext);
+		let chain_spec = ChainSpec::FlamingFir.load().map_err(|e| format!("{:?}", e))?;
+		let mut config = Configuration::<(), _, _>::default_with_spec(chain_spec);
+		config.network.transport = network::config::TransportConfig::Normal {
+			wasm_external_transport: Some(wasm_ext.clone()),
+			enable_mdns: false,
+		};
+		config.telemetry_external_transport = Some(wasm_ext);
+		config.roles = ServiceRoles::LIGHT;
+		config.name = "Browser node".to_string();
+		config.database = {
+			let db = Arc::new(kvdb_memorydb::create(10));
+			DatabaseConfig::Custom(db)
+		};
+		config
 	};
 
-	//info!("{}", version.name);
+	info!("Substrate browser node");
 	info!("  version {}", config.full_version());
 	info!("  by Parity Technologies, 2017-2019");
 	info!("Chain specification: {}", config.chain_spec.name());
 	info!("Node name: {}", config.name);
 	info!("Roles: {:?}", config.roles);
 
-	let mut service = new_full!(config)
-		.map_err(|e: String| format!("{:?}", e))?.0;
-
-	/*let informant = substrate_cli::informant::build(&service);
-	wasm_bindgen_futures::spawn_local(informant);*/
+	// Create the service. This is the most heavy initialization step.
+	let mut service = crate::service::new_light(config).map_err(|e| format!("{:?}", e))?;
 
+	// We now dispatch a background task responsible for processing the service.
+	//
+	// The main action performed by the code below consists in polling the service with
+	// `service.poll()`.
+	// The rest consists in handling RPC requests.
 	let (rpc_send_tx, mut rpc_send_rx) = mpsc::unbounded::<RpcMessage>();
 	wasm_bindgen_futures::spawn_local(futures::future::poll_fn(move || {
 		loop {

node/cli/src/lib.rs

@@ -15,6 +15,16 @@
 // along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
 
 //! Substrate CLI library.
+//!
+//! This package has two Cargo features:
+//!
+//! - `cli` (default): exposes functions that parse command-line options, then start and run the
+//! node as a CLI application.
+//!
+//! - `browser`: exposes the content of the `browser` module, which consists of exported symbols
+//! that are meant to be passed through the `wasm-bindgen` utility and called from JavaScript.
+//! Despite its name the produced WASM can theoretically also be used from NodeJS, although this
+//! hasn't been tested.
 
 #![warn(missing_docs)]
 #![warn(unused_extern_crates)]