sapi_lite/tokio/
stt.rs

1use std::ops::Deref;
2
3use tokio::sync::broadcast::error::RecvError;
4use tokio::sync::{broadcast, mpsc};
5
6use crate::stt::{Context, EventfulContext, Phrase, Recognizer};
7use crate::Result;
8
9/// A subscriber that can be awaited for recognized phrases.
10#[cfg_attr(docsrs, doc(cfg(feature = "tokio-stt")))]
11pub struct UnicastSubscriber {
12    rx: mpsc::Receiver<Phrase>,
13}
14
15impl UnicastSubscriber {
16    /// Completes when the engine recognizes a phrase.
17    pub async fn recognize(&mut self) -> Phrase {
18        self.rx.recv().await.unwrap()
19    }
20}
21
22/// The result of awaiting a [`BroadcastSubscriber`].
23#[cfg_attr(docsrs, doc(cfg(feature = "tokio-stt")))]
24#[derive(Debug, Clone, PartialEq)]
25pub enum BroadcastResult {
26    /// Holds a phrase that has been recognized
27    Phrase(Phrase),
28    /// Indicates how many phrases have been skipped because the subscriber lagged too far behind
29    Lagged(u64),
30}
31
32/// A subscriber that can be awaited for recognized phrases.
33#[cfg_attr(docsrs, doc(cfg(feature = "tokio-stt")))]
34pub struct BroadcastSubscriber {
35    rx: broadcast::Receiver<Phrase>,
36}
37
38impl BroadcastSubscriber {
39    /// Completes when the engine recognizes a phrase.
40    pub async fn recognize(&mut self) -> BroadcastResult {
41        match self.rx.recv().await {
42            Ok(phrase) => BroadcastResult::Phrase(phrase),
43            Err(RecvError::Lagged(skipped)) => BroadcastResult::Lagged(skipped),
44            Err(err) => panic!("{}", err),
45        }
46    }
47}
48
49/// A recognition context paired with a single subscriber that can be awaited for recognition.
50#[cfg_attr(docsrs, doc(cfg(feature = "tokio-stt")))]
51pub struct UnicastContext {
52    base: EventfulContext,
53}
54
55impl UnicastContext {
56    /// Creates a new recognition context for the given recognizer, configured to buffer up to the
57    /// given number of recognized phrases. If a new phrase is recognized while the buffer is full,
58    /// it will be silently dropped.
59    pub fn new(recognizer: &Recognizer, buffer: usize) -> Result<(Self, UnicastSubscriber)> {
60        let (tx, rx) = mpsc::channel::<Phrase>(buffer);
61        let handler = move |phrase| {
62            let _ = tx.try_send(phrase);
63        };
64        Ok((
65            Self {
66                base: EventfulContext::new(recognizer, handler)?,
67            },
68            UnicastSubscriber { rx },
69        ))
70    }
71}
72
73impl Deref for UnicastContext {
74    type Target = Context;
75    fn deref(&self) -> &Self::Target {
76        &self.base
77    }
78}
79
80/// A recognition context paired with a one or more subscribers that can be awaited for recognition.
81#[cfg_attr(docsrs, doc(cfg(feature = "tokio-stt")))]
82pub struct BroadcastContext {
83    base: EventfulContext,
84    tx: broadcast::Sender<Phrase>,
85}
86
87impl BroadcastContext {
88    /// Creates a new recognition context for the given recognizer, configured to buffer up to the
89    /// given number of recognized phrases. If a new phrase is recognized while one or more
90    /// subscribers haven't received it, it will be dropped and those subscribers will yield a
91    /// [`BroadcastResult::Lagged`] on next await.
92    pub fn new(recognizer: &Recognizer, buffer: usize) -> Result<(Self, BroadcastSubscriber)> {
93        let (tx, rx) = broadcast::channel::<Phrase>(buffer);
94        let handler = {
95            let tx = tx.clone();
96            move |phrase| {
97                let _ = tx.send(phrase);
98            }
99        };
100        Ok((
101            Self {
102                base: EventfulContext::new(recognizer, handler)?,
103                tx,
104            },
105            BroadcastSubscriber { rx },
106        ))
107    }
108
109    /// Creates a subscriber for this context.
110    pub fn subscribe(&self) -> BroadcastSubscriber {
111        BroadcastSubscriber {
112            rx: self.tx.subscribe(),
113        }
114    }
115}
116
117impl Deref for BroadcastContext {
118    type Target = Context;
119    fn deref(&self) -> &Self::Target {
120        &self.base
121    }
122}
sapi_lite/tokio/stt.rs

sapi_lite/tokio/
stt.rs
