morethantext/src/document/clock.rs

use crate::{
    message::{Message, MsgAction, Records},
    name::{Name, NameType, Names},
    queue::{
        data_director::{RegMsg, Register},
        router::Queue,
    },
};
use std::{
    sync::mpsc::channel,
    thread::{sleep, spawn},
    time::Duration,
};

pub struct Clock {
    queue: Queue,
}

impl Clock {
    fn new(queue: Queue) -> Self {
        Self { queue: queue }
    }

    pub fn start(mut queue: Queue) {
        let clock = Clock::new(queue.clone());
        let (tx, rx) = channel();
        let id = queue.add_sender(tx);
        let reg_msg = Register::new(id, RegMsg::AddDocName([Name::english("clock")].to_vec()));
        let msg = Message::new(NameType::None, reg_msg.clone());
        queue.send(msg);
        rx.recv().unwrap();
        spawn(move || {
            clock.listen();
        });
    }

    fn listen(&self) {
        loop {
            self.queue.send(Message::new(
                Name::english("clock"),
                MsgAction::OnUpdate(Records::new(Names::new())),
            ));
            sleep(Duration::from_secs(1));
        }
    }
}

#[cfg(test)]
mod clocks {
    use super::*;
    use crate::queue::data_director::{Include, Path};
    use chrono::{TimeDelta, Utc};

    static TIMEOUT: Duration = Duration::from_millis(1500);

    #[test]
    fn does_clock_send_reply_every_second() {
        let mut queue = Queue::new();
        let (tx, rx) = channel();
        let id = queue.add_sender(tx);
        let request = Register::new(
            id.clone(),
            RegMsg::AddRoute(Path::new(Include::All, Include::All, Include::All)),
        );
        queue.send(Message::new(NameType::None, request));
        rx.recv_timeout(TIMEOUT).unwrap();
        let mut holder: Vec<Message> = Vec::new();
        let start = Utc::now();
        Clock::start(queue.clone());
        while holder.len() < 2 {
            holder.push(rx.recv_timeout(TIMEOUT).unwrap());
        }
        let end = Utc::now();
        assert!((end - start) > TimeDelta::seconds(1));
        assert!((end - start) < TimeDelta::seconds(2));
        let reg_request = Register::new(id, RegMsg::GetNameID(Name::english("clock")));
        queue.send(Message::new(NameType::None, reg_request));
        rx.recv_timeout(TIMEOUT).unwrap();
        for msg in holder.iter() {
            let action = msg.get_action();
            match action {
                MsgAction::OnUpdate(result) => assert_eq!(result.len(), 0),
                _ => unreachable!("got {:?}, should have been empty record", action),
            }
        }
    }
}