redesign: light project site + live network status from a lusers probe

src/stats.rs

@@ -0,0 +1,101 @@
+//! Live network status, polled from the running ircd. A background task connects
+//! to the local daemon as an ordinary client every minute, runs LUSERS/VERSION,
+//! parses the reply, and stores it. If the daemon is unreachable the state simply
+//! reads "offline" — it never blocks or breaks page rendering.
+
+use std::sync::{Arc, RwLock};
+use std::time::Duration;
+use tokio::io::{AsyncBufReadExt, AsyncWriteExt, BufReader};
+use tokio::net::TcpStream;
+use tokio::time::{sleep, timeout};
+
+#[derive(Clone, Default)]
+pub struct NetStats {
+    pub online: bool,
+    pub users: Option<u64>,
+    pub version: Option<String>,
+}
+
+pub type Shared = Arc<RwLock<NetStats>>;
+
+/// Spawn the background poller. Refreshes every 60s.
+pub fn spawn_updater(shared: Shared) {
+    tokio::spawn(async move {
+        loop {
+            let next = match timeout(Duration::from_secs(7), probe()).await {
+                Ok(Some(s)) => s,
+                _ => NetStats::default(),
+            };
+            if let Ok(mut g) = shared.write() {
+                *g = next;
+            }
+            sleep(Duration::from_secs(60)).await;
+        }
+    });
+}
+
+async fn probe() -> Option<NetStats> {
+    let addr = std::env::var("ECHO_IRCD_ADDR").unwrap_or_else(|_| "127.0.0.1:6667".into());
+    let stream = TcpStream::connect(&addr).await.ok()?;
+    let (rd, mut wr) = stream.into_split();
+    wr.write_all(b"NICK echostat\r\nUSER echostat 0 * :echo website status\r\n")
+        .await
+        .ok()?;
+
+    let mut lines = BufReader::new(rd).lines();
+    let (mut users, mut version, mut asked) = (None, None, false);
+
+    for _ in 0..100 {
+        let line = match lines.next_line().await {
+            Ok(Some(l)) => l,
+            _ => break,
+        };
+        let line = line.trim_end_matches('\r');
+        if let Some(rest) = line.strip_prefix("PING ") {
+            let _ = wr.write_all(format!("PONG {rest}\r\n").as_bytes()).await;
+            continue;
+        }
+        match numeric(line) {
+            Some("001") if !asked => {
+                let _ = wr.write_all(b"LUSERS\r\nVERSION\r\n").await;
+                asked = true;
+            }
+            Some("251") => users = users.or_else(|| parse_users(line)),
+            Some("351") => version = version.or_else(|| parse_version(line)),
+            _ => {}
+        }
+        if users.is_some() && version.is_some() {
+            break;
+        }
+    }
+    let _ = wr.write_all(b"QUIT :bye\r\n").await;
+    Some(NetStats { online: true, users, version })
+}
+
+/// The three-digit numeric of an IRC line (`:src 251 nick …`), if any.
+fn numeric(line: &str) -> Option<&str> {
+    let mut it = line.split(' ');
+    let first = it.next()?;
+    let code = if first.starts_with(':') { it.next()? } else { first };
+    (code.len() == 3 && code.bytes().all(|b| b.is_ascii_digit())).then_some(code)
+}
+
+/// RPL_LUSERCLIENT trailing: "There are 5 users on 1 server" → first number.
+fn parse_users(line: &str) -> Option<u64> {
+    line.splitn(2, " :")
+        .nth(1)?
+        .split_whitespace()
+        .find_map(|w| w.parse::<u64>().ok())
+}
+
+/// RPL_VERSION trailing: "echoircd 5.0.0 · …" → "5.0.0".
+fn parse_version(line: &str) -> Option<String> {
+    let tail = line.splitn(2, " :").nth(1)?;
+    let mut it = tail.split_whitespace();
+    let a = it.next()?;
+    if a.eq_ignore_ascii_case("echoircd") {
+        it.next().map(|v| v.to_string())
+    } else {
+        Some(a.to_string())
+    }
+}