1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166

use crate::events::{LOG_CALL_TRACE_TOPIC, LOG_INPUT_TOPIC};
use crate::payload::pack;
use crate::{EResult, Error};
use busrt::client::AsyncClient;
use busrt::QoS;
use lazy_static::lazy_static;
use log::{Level, LevelFilter, Log};
use once_cell::sync::OnceCell;
use serde::Serialize;
use std::collections::HashMap;
use std::sync::Arc;
use uuid::Uuid;

tokio::task_local! {
    pub static CALL_TRACE_ID: Option<Uuid>;
}

#[derive(Serialize)]
pub struct TraceMessage {
    l: u8,
    msg: String,
}

lazy_static! {
    static ref LOG_TOPICS: HashMap<Level, String> = {
        let mut topics = HashMap::new();
        topics.insert(Level::Trace, format!("{}{}", LOG_INPUT_TOPIC, "trace"));
        topics.insert(Level::Debug, format!("{}{}", LOG_INPUT_TOPIC, "debug"));
        topics.insert(Level::Info, format!("{}{}", LOG_INPUT_TOPIC, "info"));
        topics.insert(Level::Warn, format!("{}{}", LOG_INPUT_TOPIC, "warn"));
        topics.insert(Level::Error, format!("{}{}", LOG_INPUT_TOPIC, "error"));
        topics
    };
    static ref LOG_TX: OnceCell<async_channel::Sender<(log::Level, String)>> = <_>::default();
    static ref TRACE_TX: OnceCell<async_channel::Sender<(TraceMessage, Uuid)>> = <_>::default();
}

static BUS_LOGGER: BusLogger = BusLogger {
    log_filter: OnceCell::new(),
};

struct BusLogger {
    log_filter: OnceCell<LevelFilter>,
}

impl Log for BusLogger {
    #[inline]
    fn enabled(&self, metadata: &log::Metadata) -> bool {
        !metadata.target().starts_with("busrt::") && !metadata.target().starts_with("mio::")
    }
    #[inline]
    fn log(&self, record: &log::Record) {
        if self.enabled(record.metadata()) {
            if let Some(tx) = LOG_TX.get() {
                let level = record.level();
                if level <= *self.log_filter.get().unwrap() {
                    let _r = tx.try_send((level, format!("{}", record.args())));
                }
            }
            let trid: Option<Uuid> = CALL_TRACE_ID.try_with(Clone::clone).unwrap_or_default();
            if let Some(trace_id) = trid {
                if let Some(tx) = TRACE_TX.get() {
                    let _r = tx.try_send((
                        TraceMessage {
                            l: crate::log_level_code(record.level()),
                            msg: format!("{}", record.args()),
                        },
                        trace_id,
                    ));
                }
            }
        }
    }
    #[inline]
    fn flush(&self) {}
}

async fn handle_logs<C>(
    client: Arc<tokio::sync::Mutex<C>>,
    rx: async_channel::Receiver<(Level, String)>,
) where
    C: ?Sized + AsyncClient,
{
    while let Ok((level, message)) = rx.recv().await {
        if let Err(e) = client
            .lock()
            .await
            .publish(
                LOG_TOPICS.get(&level).unwrap(),
                message.as_bytes().into(),
                QoS::No,
            )
            .await
        {
            eprintln!("{}", e);
        }
    }
}

async fn handle_traces<C>(
    client: Arc<tokio::sync::Mutex<C>>,
    rx: async_channel::Receiver<(TraceMessage, Uuid)>,
) where
    C: ?Sized + AsyncClient,
{
    while let Ok((trace_message, trace_id)) = rx.recv().await {
        let trace_topic = format!("{}{}", LOG_CALL_TRACE_TOPIC, trace_id);
        match pack(&trace_message) {
            Ok(payload) => {
                if let Err(e) = client
                    .lock()
                    .await
                    .publish(&trace_topic, payload.into(), QoS::No)
                    .await
                {
                    eprintln!("{}", e);
                }
            }
            Err(e) => eprintln!("{}", e),
        }
    }
}

/// Must not be called twice
///
pub fn init_bus<C>(
    client: Arc<tokio::sync::Mutex<C>>,
    queue_size: usize,
    filter: LevelFilter,
    call_tracing: bool,
) -> EResult<()>
where
    C: ?Sized + AsyncClient + 'static,
{
    let (tx, rx) = async_channel::bounded(queue_size);
    LOG_TX
        .set(tx)
        .map_err(|_| Error::failed("Unable to set LOG_TX"))?;
    let cl = client.clone();
    tokio::spawn(async move {
        handle_logs(cl, rx).await;
    });
    if call_tracing {
        let (tx, rx) = async_channel::bounded(queue_size);
        TRACE_TX
            .set(tx)
            .map_err(|_| Error::failed("Unable to set TRACE_TX"))?;
        tokio::spawn(async move {
            handle_traces(client, rx).await;
        });
    }
    BUS_LOGGER
        .log_filter
        .set(filter)
        .map_err(|_| Error::failed("Unable to set BUS_LOGGER filter"))?;
    log::set_logger(&BUS_LOGGER)
        .map(|()| {
            log::set_max_level(if call_tracing {
                LevelFilter::Trace
            } else {
                filter
            });
        })
        .map_err(Error::failed)?;
    Ok(())
}