connect to substrate using ws (#417)

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(),
 		}