jsonrpc_pubsub/
typed.rs

1//! PUB-SUB auto-serializing structures.
2
3use std::marker::PhantomData;
4use std::pin::Pin;
5
6use crate::subscription;
7use crate::types::{SinkResult, SubscriptionId, TransportError};
8
9use crate::core::futures::task::{Context, Poll};
10use crate::core::futures::{self, channel};
11use crate::core::{self, Error, Params, Value};
12
13/// New PUB-SUB subscriber.
14#[derive(Debug)]
15pub struct Subscriber<T, E = Error> {
16	subscriber: subscription::Subscriber,
17	_data: PhantomData<(T, E)>,
18}
19
20impl<T, E> Subscriber<T, E> {
21	/// Wrap non-typed subscriber.
22	pub fn new(subscriber: subscription::Subscriber) -> Self {
23		Subscriber {
24			subscriber,
25			_data: PhantomData,
26		}
27	}
28
29	/// Create new subscriber for tests.
30	pub fn new_test<M: Into<String>>(
31		method: M,
32	) -> (
33		Self,
34		crate::oneshot::Receiver<Result<SubscriptionId, Error>>,
35		channel::mpsc::UnboundedReceiver<String>,
36	) {
37		let (subscriber, id, subscription) = subscription::Subscriber::new_test(method);
38		(Subscriber::new(subscriber), id, subscription)
39	}
40
41	/// Reject subscription with given error.
42	pub fn reject(self, error: Error) -> Result<(), ()> {
43		self.subscriber.reject(error)
44	}
45
46	/// Reject subscription with given error.
47	///
48	/// The returned future will resolve when the response is sent to the client.
49	pub async fn reject_async(self, error: Error) -> Result<(), ()> {
50		self.subscriber.reject_async(error).await
51	}
52
53	/// Assign id to this subscriber.
54	/// This method consumes `Subscriber` and returns `Sink`
55	/// if the connection is still open or error otherwise.
56	pub fn assign_id(self, id: SubscriptionId) -> Result<Sink<T, E>, ()> {
57		let sink = self.subscriber.assign_id(id.clone())?;
58		Ok(Sink {
59			id,
60			sink,
61			_data: PhantomData,
62		})
63	}
64
65	/// Assign id to this subscriber.
66	/// This method consumes `Subscriber` and resolves to `Sink`
67	/// if the connection is still open and the id has been sent or to error otherwise.
68	pub async fn assign_id_async(self, id: SubscriptionId) -> Result<Sink<T, E>, ()> {
69		let sink = self.subscriber.assign_id_async(id.clone()).await?;
70		Ok(Sink {
71			id,
72			sink,
73			_data: PhantomData,
74		})
75	}
76}
77
78/// Subscriber sink.
79#[derive(Debug, Clone)]
80pub struct Sink<T, E = Error> {
81	sink: subscription::Sink,
82	id: SubscriptionId,
83	_data: PhantomData<(T, E)>,
84}
85
86impl<T: serde::Serialize, E: serde::Serialize> Sink<T, E> {
87	/// Sends a notification to the subscriber.
88	pub fn notify(&self, val: Result<T, E>) -> SinkResult {
89		self.sink.notify(self.val_to_params(val))
90	}
91
92	fn to_value<V>(value: V) -> Value
93	where
94		V: serde::Serialize,
95	{
96		core::to_value(value).expect("Expected always-serializable type.")
97	}
98
99	fn val_to_params(&self, val: Result<T, E>) -> Params {
100		let id = self.id.clone().into();
101		let val = val.map(Self::to_value).map_err(Self::to_value);
102
103		Params::Map(
104			vec![
105				("subscription".to_owned(), id),
106				match val {
107					Ok(val) => ("result".to_owned(), val),
108					Err(err) => ("error".to_owned(), err),
109				},
110			]
111			.into_iter()
112			.collect(),
113		)
114	}
115}
116
117impl<T: serde::Serialize + Unpin, E: serde::Serialize + Unpin> futures::sink::Sink<Result<T, E>> for Sink<T, E> {
118	type Error = TransportError;
119
120	fn poll_ready(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
121		Pin::new(&mut self.sink).poll_ready(cx)
122	}
123
124	fn start_send(mut self: Pin<&mut Self>, item: Result<T, E>) -> Result<(), Self::Error> {
125		let val = self.val_to_params(item);
126		Pin::new(&mut self.sink).start_send(val)
127	}
128
129	fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
130		Pin::new(&mut self.sink).poll_flush(cx)
131	}
132
133	fn poll_close(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
134		Pin::new(&mut self.sink).poll_close(cx)
135	}
136}
jsonrpc_pubsub/typed.rs

jsonrpc_pubsub/
typed.rs
