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
use crossbeam_channel::{unbounded, Sender};
use serde_json::json;
use std::net::SocketAddr;
use std::sync::{Arc, Mutex};
use std::thread;
use tiny_http::{Response, Server};
use tracing::Subscriber;
use tracing_subscriber::layer::Layer;
use tracing_subscriber::registry::LookupSpan;

pub struct Log {
    sender: Sender<String>,
}

impl Log {
    pub fn builder() -> LogBuilder { LogBuilder::new() }
}

pub struct LogBuilder {
    host: String,
}

impl LogBuilder {
    fn new() -> Self { LogBuilder { host: "127.0.0.1:8362".to_string() } }

    pub fn with_host(mut self, host: &str) -> Self {
        self.host = host.to_string();
        self
    }

    pub fn build(self) -> Log {
        let (sender, receiver) = unbounded();
        let addr: SocketAddr = self.host.parse().expect("Invalid host address");

        thread::spawn(move || {
            let server = Server::http(addr).expect("Failed to start server");
            let receiver = Arc::new(receiver);
            let cache = Arc::new(Mutex::new(Vec::new()));

            for request in server.incoming_requests() {
                let receiver = receiver.clone();
                let cache = cache.clone();
                thread::spawn(move || {
                    let mut cache = cache.lock().unwrap();
                    cache.extend(receiver.try_iter());
                    let logs = cache.clone();
                    let json = json!({ "logs": logs });
                    let response = Response::from_string(json.to_string()).with_header(tiny_http::Header::from_bytes(&b"Content-Type"[..], &b"application/json"[..]).unwrap());
                    request.respond(response).expect("Failed to send response");
                });
            }
        });

        Log { sender }
    }
}

impl<S> Layer<S> for Log
where
    S: Subscriber + for<'a> LookupSpan<'a>,
{
    fn on_event(&self, event: &tracing::Event<'_>, _ctx: tracing_subscriber::layer::Context<'_, S>) {
        let mut visitor = JsonVisitor::default();
        event.record(&mut visitor);
        let log_entry = serde_json::to_string(&visitor.fields).unwrap();
        self.sender.send(log_entry).expect("Failed to send log entry");
    }
}

#[derive(Default)]
struct JsonVisitor {
    fields: serde_json::Map<String, serde_json::Value>,
}

impl tracing::field::Visit for JsonVisitor {
    fn record_debug(&mut self, field: &tracing::field::Field, value: &dyn std::fmt::Debug) { self.fields.insert(field.name().to_string(), json!(format!("{:?}", value))); }

    fn record_str(&mut self, field: &tracing::field::Field, value: &str) { self.fields.insert(field.name().to_string(), json!(value)); }

    fn record_i64(&mut self, field: &tracing::field::Field, value: i64) { self.fields.insert(field.name().to_string(), json!(value)); }

    fn record_u64(&mut self, field: &tracing::field::Field, value: u64) { self.fields.insert(field.name().to_string(), json!(value)); }

    fn record_bool(&mut self, field: &tracing::field::Field, value: bool) { self.fields.insert(field.name().to_string(), json!(value)); }
}

#[cfg(test)]
mod tests {
    use super::*;
    use reqwest::blocking::Client;
    use std::{thread, time::Duration};
    use tracing_subscriber::prelude::*;

    #[test]
    fn test_weblog() {
        let log_port = 8363;
        tracing_subscriber::registry().with(Log::builder().with_host(&format!("127.0.0.1:{}", log_port)).build()).init();

        thread::sleep(Duration::from_secs(1));

        tracing::info!("Test log message 1");
        tracing::warn!("Test log message 2");
        tracing::error!("Test log message 3");

        thread::sleep(Duration::from_millis(500));

        let client = Client::new();
        let response = client.get(&format!("http://127.0.0.1:{}", log_port)).send().expect("Failed to send request");

        assert!(response.status().is_success());

        let body: serde_json::Value = response.json().expect("Failed to parse JSON");
        let logs = body["logs"].as_array().expect("Logs should be an array");

        assert!(logs.iter().any(|log| log.to_string().contains("Test log message 1")));
        assert!(logs.iter().any(|log| log.to_string().contains("Test log message 2")));
        assert!(logs.iter().any(|log| log.to_string().contains("Test log message 3")));

        // Test caching
        tracing::info!("Test log message 4");
        thread::sleep(Duration::from_millis(500));

        let response = client.get(&format!("http://127.0.0.1:{}", log_port)).send().expect("Failed to send request");

        let body: serde_json::Value = response.json().expect("Failed to parse JSON");
        let logs = body["logs"].as_array().expect("Logs should be an array");

        assert!(logs.iter().any(|log| log.to_string().contains("Test log message 1")));
        assert!(logs.iter().any(|log| log.to_string().contains("Test log message 2")));
        assert!(logs.iter().any(|log| log.to_string().contains("Test log message 3")));
        assert!(logs.iter().any(|log| log.to_string().contains("Test log message 4")));
    }
}