Updates

reference_jsonrpsee_crate_examples/ws_pubsub_with_params.rs

@@ -0,0 +1,138 @@
+// Copyright 2019-2021 Parity Technologies (UK) Ltd.
+//
+// Permission is hereby granted, free of charge, to any
+// person obtaining a copy of this software and associated
+// documentation files (the "Software"), to deal in the
+// Software without restriction, including without
+// limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of
+// the Software, and to permit persons to whom the Software
+// is furnished to do so, subject to the following
+// conditions:
+//
+// The above copyright notice and this permission notice
+// shall be included in all copies or substantial portions
+// of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+// TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+// PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+// SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+// IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+use std::net::SocketAddr;
+use std::time::Duration;
+
+use futures::{Stream, StreamExt};
+use jsonrpsee::core::Serialize;
+use jsonrpsee::core::client::{Subscription, SubscriptionClientT};
+use jsonrpsee::server::{RpcModule, Server, ServerConfig, TrySendError};
+use jsonrpsee::ws_client::WsClientBuilder;
+use jsonrpsee::{PendingSubscriptionSink, rpc_params};
+use tokio::time::interval;
+use tokio_stream::wrappers::IntervalStream;
+
+#[tokio::main]
+async fn main() -> anyhow::Result<()> {
+	tracing_subscriber::FmtSubscriber::builder()
+		.with_env_filter(tracing_subscriber::EnvFilter::from_default_env())
+		.try_init()
+		.expect("setting default subscriber failed");
+
+	let addr = run_server().await?;
+	let url = format!("ws://{}", addr);
+
+	let client = WsClientBuilder::default().build(&url).await?;
+
+	// Subscription with a single parameter
+	let mut sub_params_one: Subscription<Option<char>> =
+		client.subscribe("sub_one_param", rpc_params![3], "unsub_one_param").await?;
+	tracing::info!("subscription with one param: {:?}", sub_params_one.next().await);
+
+	// Subscription with multiple parameters
+	let mut sub_params_two: Subscription<String> =
+		client.subscribe("sub_params_two", rpc_params![2, 5], "unsub_params_two").await?;
+	tracing::info!("subscription with two params: {:?}", sub_params_two.next().await);
+
+	Ok(())
+}
+
+async fn run_server() -> anyhow::Result<SocketAddr> {
+	const LETTERS: &str = "abcdefghijklmnopqrstuvxyz";
+	let config = ServerConfig::builder().set_message_buffer_capacity(10).build();
+	let server = Server::builder().set_config(config).build("127.0.0.1:0").await?;
+	let mut module = RpcModule::new(());
+	module
+		.register_subscription(
+			"sub_one_param",
+			"sub_one_param",
+			"unsub_one_param",
+			|params, pending, _, _| async move {
+				// we are doing this verbose way to get a customized reject error on the subscription.
+				let idx = match params.one::<usize>() {
+					Ok(p) => p,
+					Err(e) => {
+						let _ = pending.reject(e).await;
+						return Ok(());
+					}
+				};
+
+				let item = LETTERS.chars().nth(idx);
+
+				let interval = interval(Duration::from_millis(200));
+				let stream = IntervalStream::new(interval).map(move |_| item);
+
+				pipe_from_stream_and_drop(pending, stream).await.map_err(Into::into)
+			},
+		)
+		.unwrap();
+	module
+		.register_subscription("sub_params_two", "params_two", "unsub_params_two", |params, pending, _, _| async move {
+			let (one, two) = params.parse::<(usize, usize)>()?;
+
+			let item = &LETTERS[one..two];
+			let interval = interval(Duration::from_millis(200));
+			let stream = IntervalStream::new(interval).map(move |_| item);
+			pipe_from_stream_and_drop(pending, stream).await.map_err(Into::into)
+		})
+		.unwrap();
+
+	let addr = server.local_addr()?;
+	let handle = server.start(module);
+
+	// In this example we don't care about doing shutdown so let's it run forever.
+	// You may use the `ServerHandle` to shut it down or manage it yourself.
+	tokio::spawn(handle.stopped());
+
+	Ok(addr)
+}
+
+pub async fn pipe_from_stream_and_drop<T: Serialize>(
+	pending: PendingSubscriptionSink,
+	mut stream: impl Stream<Item = T> + Unpin,
+) -> Result<(), anyhow::Error> {
+	let mut sink = pending.accept().await?;
+
+	loop {
+		tokio::select! {
+			_ = sink.closed() => break Err(anyhow::anyhow!("Subscription was closed")),
+			maybe_item = stream.next() => {
+				let item = match maybe_item {
+					Some(item) => item,
+					None => break Err(anyhow::anyhow!("Subscription was closed")),
+				};
+				let msg = serde_json::value::to_raw_value(&item)?;
+				match sink.try_send(msg) {
+					Ok(_) => (),
+					Err(TrySendError::Closed(_)) => break Err(anyhow::anyhow!("Subscription was closed")),
+					// channel is full, let's be naive an just drop the message.
+					Err(TrySendError::Full(_)) => (),
+				}
+			}
+		}
+	}
+}