use std::marker::PhantomData;
use crate::subscription;
use crate::types::{SinkResult, SubscriptionId, TransportError};
use serde;
use crate::core::futures::{self, sync, Future, Sink as FuturesSink};
use crate::core::{self, Error, Params, Value};
#[derive(Debug)]
pub struct Subscriber<T, E = Error> {
subscriber: subscription::Subscriber,
_data: PhantomData<(T, E)>,
}
impl<T, E> Subscriber<T, E> {
pub fn new(subscriber: subscription::Subscriber) -> Self {
Subscriber {
subscriber,
_data: PhantomData,
}
}
pub fn new_test<M: Into<String>>(
method: M,
) -> (
Self,
crate::oneshot::Receiver<Result<SubscriptionId, Error>>,
sync::mpsc::Receiver<String>,
) {
let (subscriber, id, subscription) = subscription::Subscriber::new_test(method);
(Subscriber::new(subscriber), id, subscription)
}
pub fn reject(self, error: Error) -> Result<(), ()> {
self.subscriber.reject(error)
}
pub fn reject_async(self, error: Error) -> impl Future<Item = (), Error = ()> {
self.subscriber.reject_async(error)
}
pub fn assign_id(self, id: SubscriptionId) -> Result<Sink<T, E>, ()> {
self.subscriber.assign_id(id.clone()).map(|sink| Sink {
id,
sink,
buffered: None,
_data: PhantomData,
})
}
pub fn assign_id_async(self, id: SubscriptionId) -> impl Future<Item = Sink<T, E>, Error = ()> {
self.subscriber.assign_id_async(id.clone()).map(|sink| Sink {
id,
sink,
buffered: None,
_data: PhantomData,
})
}
}
#[derive(Debug, Clone)]
pub struct Sink<T, E = Error> {
sink: subscription::Sink,
id: SubscriptionId,
buffered: Option<Params>,
_data: PhantomData<(T, E)>,
}
impl<T: serde::Serialize, E: serde::Serialize> Sink<T, E> {
pub fn notify(&self, val: Result<T, E>) -> SinkResult {
self.sink.notify(self.val_to_params(val))
}
fn to_value<V>(value: V) -> Value
where
V: serde::Serialize,
{
core::to_value(value).expect("Expected always-serializable type.")
}
fn val_to_params(&self, val: Result<T, E>) -> Params {
let id = self.id.clone().into();
let val = val.map(Self::to_value).map_err(Self::to_value);
Params::Map(
vec![
("subscription".to_owned(), id),
match val {
Ok(val) => ("result".to_owned(), val),
Err(err) => ("error".to_owned(), err),
},
]
.into_iter()
.collect(),
)
}
fn poll(&mut self) -> futures::Poll<(), TransportError> {
if let Some(item) = self.buffered.take() {
let result = self.sink.start_send(item)?;
if let futures::AsyncSink::NotReady(item) = result {
self.buffered = Some(item);
}
}
if self.buffered.is_some() {
Ok(futures::Async::NotReady)
} else {
Ok(futures::Async::Ready(()))
}
}
}
impl<T: serde::Serialize, E: serde::Serialize> futures::sink::Sink for Sink<T, E> {
type SinkItem = Result<T, E>;
type SinkError = TransportError;
fn start_send(&mut self, item: Self::SinkItem) -> futures::StartSend<Self::SinkItem, Self::SinkError> {
if self.poll()?.is_not_ready() {
return Ok(futures::AsyncSink::NotReady(item));
}
let val = self.val_to_params(item);
self.buffered = Some(val);
self.poll()?;
Ok(futures::AsyncSink::Ready)
}
fn poll_complete(&mut self) -> futures::Poll<(), Self::SinkError> {
self.poll()?;
self.sink.poll_complete()
}
fn close(&mut self) -> futures::Poll<(), Self::SinkError> {
self.poll()?;
self.sink.close()
}
}