initial version

.gitignore

@@ -1,2 +1,4 @@
 /target
 **/*.rs.bk
+.env
+key*

Cargo.toml

@@ -7,3 +7,8 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+ssh2 = "0.7.1"
+dotenv = "0.15.0"
+main_error = "0.1.0"
+tokio = { version = "0.2", features = ["macros"] }
+warp = "0.2"

src/main.rs

@@ -1,3 +1,61 @@
-fn main() {
+use std::io::prelude::*;
-    println!("Hello, world!");
+use std::net::{TcpStream, ToSocketAddrs};
+use ssh2::Session;
+use main_error::MainError;
+use std::collections::HashMap;
+use std::path::Path;
+use warp::Filter;
+use std::ffi::OsStr;
+use std::sync::Arc;
+
+struct WifiLister {
+    session: Session
 }
+
+impl WifiLister {
+    pub fn new<A: ToSocketAddrs, S: AsRef<OsStr> + ?Sized>(addr: A, keyfile: &S) -> Result<Self, MainError> {
+        let tcp = TcpStream::connect(addr)?;
+        let mut session = Session::new()?;
+        session.set_tcp_stream(tcp);
+        session.handshake()?;
+        let key_file = Path::new(keyfile);
+        session.userauth_pubkey_file("admin", None, &key_file, None)?;
+
+        Ok(WifiLister {
+            session
+        })
+    }
+
+    pub fn list_connected_devices(&self) -> Result<Vec<String>, MainError> {
+        let mut channel = self.session.channel_session()?;
+        channel.exec("wl assoclist")?;
+        let mut s = String::new();
+        channel.read_to_string(&mut s)?;
+        channel.wait_close()?;
+
+        Ok(s.lines().map(|s| s.trim_start_matches("assoclist ").to_string()).collect())
+    }
+}
+
+#[tokio::main]
+async fn main() -> Result<(), MainError> {
+    let mut env: HashMap<String, String> = dotenv::vars().collect();
+    let addr = env.remove("ADDR").ok_or("No ADDR set")?;
+    let keyfile = env.remove("KEYFILE").ok_or("No KEYFILE set")?;
+
+    let wifi_listener = Arc::new(WifiLister::new(addr, &keyfile)?);
+
+    // GET /hello/warp => 200 OK with body "Hello, warp!"
+    let metrics = warp::path!("metrics")
+        .map(move || {
+            let mac_addresses = wifi_listener.list_connected_devices().unwrap_or_default();
+            let lines: Vec<_> = mac_addresses.into_iter().map(|mac| format!("wifi_client{{mac=\"{}\"}} 1", mac)).collect();
+            lines.join("\n")
+        });
+
+    warp::serve(metrics)
+        .run(([127, 0, 0, 1], 3030u16))
+        .await;
+
+    Ok(())
+}