tether/core/examples/iroh_engine.rs

//! M4 integration test — the real `Engine` syncing a clipboard over iroh.
//!   cargo run --features iroh-transport --example iroh_engine
//!
//! Two engines, same account → same room → same gossip topic. No SSE/RTC/LAN:
//! with the iroh-transport feature the engine's only transport is IrohTransport.
//! Proves the public API (Engine::new/start/send + MessageHandler) is unchanged
//! while the entire Mesh underneath is iroh — the payoff of the MeshEvent seam.
//!
//! Bootstrap is wired in-process via the TETHER_IROH_BOOTSTRAP env var (the v1
//! stopgap until the rendezvous supernode): start A, read its EndpointId, hand
//! it to B.

use std::sync::mpsc;
use std::time::{Duration, Instant};

use tethercore::{Engine, Message, MessageHandler};

struct Noop;
impl MessageHandler for Noop {
    fn on_message(&self, _m: Message) {}
    fn on_status(&self, _c: bool) {}
    fn on_file(&self, _n: String, _m: String, _d: Vec<u8>) {}
}

struct Collector {
    text: mpsc::Sender<String>,
    file: mpsc::Sender<(String, usize)>,
}
impl MessageHandler for Collector {
    fn on_message(&self, m: Message) {
        let _ = self.text.send(m.text);
    }
    fn on_status(&self, _c: bool) {}
    fn on_file(&self, name: String, _mime: String, data: Vec<u8>) {
        let _ = self.file.send((name, data.len()));
    }
}

fn main() {
    let account = "pecord@gmail.com"; // same account → same room → same topic + key
    let room = "iroh-engine-test";
    let server = "unused"; // iroh ignores cfg.server; it uses n0 infra

    // Opener (no bootstrap yet).
    let a = Engine::new(
        server.into(), room.into(), "iroh-a".into(), "macos".into(), "A".into(), account.into(),
    );
    a.start(Box::new(Noop));

    // Wait for A's iroh endpoint to come online, then bootstrap B off it.
    let a_id = {
        let deadline = Instant::now() + Duration::from_secs(20);
        loop {
            if let Some(id) = a.iroh_id() {
                break id;
            }
            if Instant::now() > deadline {
                eprintln!("❌ A never came online");
                std::process::exit(1);
            }
            std::thread::sleep(Duration::from_millis(200));
        }
    };
    eprintln!("A online, id={a_id}");
    std::env::set_var("TETHER_IROH_BOOTSTRAP", &a_id);

    // Joiner (bootstraps to A via the env var its IrohTransport reads at start).
    let (tx, rx) = mpsc::channel();
    let (ftx, frx) = mpsc::channel();
    let b = Engine::new(
        server.into(), room.into(), "iroh-b".into(), "ios".into(), "B".into(), account.into(),
    );
    b.start(Box::new(Collector { text: tx, file: ftx }));

    eprintln!("waiting for gossip topic to form…");
    std::thread::sleep(Duration::from_secs(8));

    // 1) Text clipboard over gossip.
    let payload = "clipboard synced over iroh 🎉";
    eprintln!("A sending text: {payload:?}");
    a.send(payload.to_string());
    match rx.recv_timeout(Duration::from_secs(10)) {
        Ok(t) if t == payload => {
            println!("✅ text: B received {t:?} (E2E-decrypted, via gossip)");
        }
        Ok(t) => {
            println!("⚠️  B got {t:?} (expected {payload:?})");
            std::process::exit(1);
        }
        Err(_) => {
            println!("❌ B received no text");
            std::process::exit(1);
        }
    }

    // 2) A "photo"/blob over iroh-blobs (announced via gossip, fetched P2P).
    let photo: Vec<u8> = (0..200_000u32).map(|i| (i % 251) as u8).collect();
    eprintln!("A sending blob: photo.bin ({} bytes)", photo.len());
    a.send_file("photo.bin".into(), "image/png".into(), photo.clone());
    match frx.recv_timeout(Duration::from_secs(15)) {
        Ok((name, len)) if len == photo.len() => {
            println!("✅ blob: B received {name:?} ({len} bytes, E2E-decrypted, via iroh-blobs)");
        }
        Ok((name, len)) => {
            println!("⚠️  B got {name:?} with {len} bytes (expected {})", photo.len());
            std::process::exit(1);
        }
        Err(_) => {
            println!("❌ B received no blob");
            std::process::exit(1);
        }
    }

    println!("🎉 engine-over-iroh: text + photo synced, no SSE/RTC/LAN/relay");
    a.stop();
    b.stop();
}