connect to substrate using ws (paritytech#417)

bridges/relays/ethereum/src/cli.yml

@@ -24,7 +24,7 @@ subcommands:
             - sub-port: &sub-port
                 long: sub-port
                 value_name: SUB_PORT
-                help: Connect to Substrate node at given port.
+                help: Connect to Substrate node websocket server at given port.
                 takes_value: true
             - sub-tx-mode:
                 long: sub-tx-mode

bridges/relays/substrate-client/Cargo.toml

@@ -8,7 +8,7 @@ license = "GPL-3.0-or-later WITH Classpath-exception-2.0"
 [dependencies]
 async-trait = "0.1.40"
 codec = { package = "parity-scale-codec", version = "1.3.4" }
-jsonrpsee = { git = "https://github.com/svyatonik/jsonrpsee.git", branch = "shared-client-in-rpc-api", default-features = false, features = ["http"] }
+jsonrpsee = { git = "https://github.com/svyatonik/jsonrpsee.git", branch = "shared-client-in-rpc-api", default-features = false, features = ["ws"] }
 log = "0.4.11"
 num-traits = "0.2"
 

bridges/relays/substrate-client/src/client.rs

@@ -22,7 +22,7 @@ use crate::{ConnectionParams, Result};
 
 use jsonrpsee::common::DeserializeOwned;
 use jsonrpsee::raw::RawClient;
-use jsonrpsee::transport::http::HttpTransportClient;
+use jsonrpsee::transport::ws::WsTransportClient;
 use jsonrpsee::Client as RpcClient;
 use num_traits::Zero;
 use sp_core::Bytes;
@@ -49,10 +49,10 @@ impl<C: Chain> std::fmt::Debug for Client<C> {
 }
 
 impl<C: Chain> Client<C> {
-	/// Returns client that is able to call RPCs on Substrate node.
+	/// Returns client that is able to call RPCs on Substrate node over websocket connection.
 	pub async fn new(params: ConnectionParams) -> Result<Self> {
-		let uri = format!("http://{}:{}", params.host, params.port);
-		let transport = HttpTransportClient::new(&uri);
+		let uri = format!("ws://{}:{}", params.host, params.port);
+		let transport = WsTransportClient::new(&uri).await?;
 		let raw_client = RawClient::new(transport);
 		let client: RpcClient = raw_client.into();
 

bridges/relays/substrate-client/src/error.rs

@@ -17,6 +17,7 @@
 //! Substrate node RPC errors.
 
 use jsonrpsee::client::RequestError;
+use jsonrpsee::transport::ws::WsNewDnsError;
 use relay_utils::MaybeConnectionError;
 
 /// Result type used by Substrate client.
@@ -26,13 +27,21 @@ pub type Result<T> = std::result::Result<T, Error>;
 /// a Substrate node through RPC.
 #[derive(Debug)]
 pub enum Error {
+	/// Web socket connection error.
+	WsConnectionError(WsNewDnsError),
 	/// An error that can occur when making an HTTP request to
-	/// an JSON-RPC client.
+	/// an JSON-RPC server.
 	Request(RequestError),
-	/// The response from the client could not be SCALE decoded.
+	/// The response from the server could not be SCALE decoded.
 	ResponseParseFailed(codec::Error),
 }
 
+impl From<WsNewDnsError> for Error {
+	fn from(error: WsNewDnsError) -> Self {
+		Error::WsConnectionError(error)
+	}
+}
+
 impl From<RequestError> for Error {
 	fn from(error: RequestError) -> Self {
 		Error::Request(error)
@@ -54,6 +63,7 @@ impl From<Error> for String {
 impl ToString for Error {
 	fn to_string(&self) -> String {
 		match self {
+			Self::WsConnectionError(e) => e.to_string(),
 			Self::Request(e) => e.to_string(),
 			Self::ResponseParseFailed(e) => e.what().to_string(),
 		}

bridges/relays/substrate-client/src/lib.rs

@@ -30,20 +30,20 @@ pub use crate::client::{Client, OpaqueGrandpaAuthoritiesSet};
 pub use crate::error::{Error, Result};
 pub use bp_runtime::{BlockNumberOf, Chain as ChainBase, HashOf, HeaderOf};
 
-/// Substrate connection params.
+/// Substrate-over-websocket connection params.
 #[derive(Debug, Clone)]
 pub struct ConnectionParams {
-	/// Substrate RPC host.
+	/// Websocket server hostname.
 	pub host: String,
-	/// Substrate RPC port.
+	/// Websocket server TCP port.
 	pub port: u16,
 }
 
 impl Default for ConnectionParams {
 	fn default() -> Self {
 		ConnectionParams {
 			host: "localhost".into(),
-			port: 9933,
+			port: 9944,
 		}
 	}
 }

bridges/relays/substrate/src/cli.rs

@@ -76,7 +76,7 @@ macro_rules! declare_chain_options {
 				#[doc = "Connect to " $chain " node at given host."]
 				#[structopt(long)]
 				pub [<$chain_prefix _host>]: String,
-				#[doc = "Connect to " $chain " node at given port."]
+				#[doc = "Connect to " $chain " node websocket server at given port."]
 				#[structopt(long)]
 				pub [<$chain_prefix _port>]: u16,
 			}