rpc.rs

  1use crate::util::ResultExt;
  2use anyhow::{anyhow, Context, Result};
  3use async_tungstenite::tungstenite::http::Request;
  4use gpui::{AsyncAppContext, Entity, ModelContext, Task};
  5use lazy_static::lazy_static;
  6use parking_lot::RwLock;
  7use postage::{prelude::Stream, watch};
  8use std::{
  9    any::TypeId,
 10    collections::HashMap,
 11    convert::TryFrom,
 12    future::Future,
 13    sync::{Arc, Weak},
 14    time::{Duration, Instant},
 15};
 16use surf::Url;
 17pub use zrpc::{proto, ConnectionId, PeerId, TypedEnvelope};
 18use zrpc::{
 19    proto::{AnyTypedEnvelope, EntityMessage, EnvelopedMessage, RequestMessage},
 20    Conn, Peer, Receipt,
 21};
 22
 23lazy_static! {
 24    static ref ZED_SERVER_URL: String =
 25        std::env::var("ZED_SERVER_URL").unwrap_or("https://zed.dev:443".to_string());
 26}
 27
 28pub struct Client {
 29    peer: Arc<Peer>,
 30    state: RwLock<ClientState>,
 31    auth_callback: Option<
 32        Box<dyn 'static + Send + Sync + Fn(&AsyncAppContext) -> Task<Result<(u64, String)>>>,
 33    >,
 34    connect_callback: Option<
 35        Box<dyn 'static + Send + Sync + Fn(u64, &str, &AsyncAppContext) -> Task<Result<Conn>>>,
 36    >,
 37}
 38
 39#[derive(Copy, Clone, Debug)]
 40pub enum Status {
 41    Disconnected,
 42    Authenticating,
 43    Connecting {
 44        user_id: u64,
 45    },
 46    ConnectionError,
 47    Connected {
 48        connection_id: ConnectionId,
 49        user_id: u64,
 50    },
 51    ConnectionLost,
 52    Reauthenticating,
 53    Reconnecting {
 54        user_id: u64,
 55    },
 56    ReconnectionError {
 57        next_reconnection: Instant,
 58    },
 59}
 60
 61struct ClientState {
 62    status: (watch::Sender<Status>, watch::Receiver<Status>),
 63    entity_id_extractors: HashMap<TypeId, Box<dyn Send + Sync + Fn(&dyn AnyTypedEnvelope) -> u64>>,
 64    model_handlers: HashMap<
 65        (TypeId, u64),
 66        Box<dyn Send + Sync + FnMut(Box<dyn AnyTypedEnvelope>, &mut AsyncAppContext)>,
 67    >,
 68    _maintain_connection: Option<Task<()>>,
 69    heartbeat_interval: Duration,
 70}
 71
 72impl Default for ClientState {
 73    fn default() -> Self {
 74        Self {
 75            status: watch::channel_with(Status::Disconnected),
 76            entity_id_extractors: Default::default(),
 77            model_handlers: Default::default(),
 78            _maintain_connection: None,
 79            heartbeat_interval: Duration::from_secs(5),
 80        }
 81    }
 82}
 83
 84pub struct Subscription {
 85    client: Weak<Client>,
 86    id: (TypeId, u64),
 87}
 88
 89impl Drop for Subscription {
 90    fn drop(&mut self) {
 91        if let Some(client) = self.client.upgrade() {
 92            drop(
 93                client
 94                    .state
 95                    .write()
 96                    .model_handlers
 97                    .remove(&self.id)
 98                    .unwrap(),
 99            );
100        }
101    }
102}
103
104impl Client {
105    pub fn new() -> Arc<Self> {
106        Arc::new(Self {
107            peer: Peer::new(),
108            state: Default::default(),
109            auth_callback: None,
110            connect_callback: None,
111        })
112    }
113
114    #[cfg(any(test, feature = "test-support"))]
115    pub fn set_login_and_connect_callbacks<Login, Connect>(
116        &mut self,
117        login: Login,
118        connect: Connect,
119    ) where
120        Login: 'static + Send + Sync + Fn(&AsyncAppContext) -> Task<Result<(u64, String)>>,
121        Connect: 'static + Send + Sync + Fn(u64, &str, &AsyncAppContext) -> Task<Result<Conn>>,
122    {
123        self.auth_callback = Some(Box::new(login));
124        self.connect_callback = Some(Box::new(connect));
125    }
126
127    pub fn status(&self) -> watch::Receiver<Status> {
128        self.state.read().status.1.clone()
129    }
130
131    fn set_status(self: &Arc<Self>, status: Status, cx: &AsyncAppContext) {
132        let mut state = self.state.write();
133        *state.status.0.borrow_mut() = status;
134
135        match status {
136            Status::Connected { .. } => {
137                let heartbeat_interval = state.heartbeat_interval;
138                let this = self.clone();
139                let foreground = cx.foreground();
140                state._maintain_connection = Some(cx.foreground().spawn(async move {
141                    let mut next_ping_id = 0;
142                    loop {
143                        foreground.timer(heartbeat_interval).await;
144                        this.request(proto::Ping { id: next_ping_id })
145                            .await
146                            .unwrap();
147                        next_ping_id += 1;
148                    }
149                }));
150            }
151            Status::ConnectionLost => {
152                let this = self.clone();
153                let foreground = cx.foreground();
154                state._maintain_connection = Some(cx.spawn(|cx| async move {
155                    let mut delay_seconds = 5;
156                    while let Err(error) = this.authenticate_and_connect(&cx).await {
157                        log::error!("failed to connect {}", error);
158                        let delay = Duration::from_secs(delay_seconds);
159                        this.set_status(
160                            Status::ReconnectionError {
161                                next_reconnection: Instant::now() + delay,
162                            },
163                            &cx,
164                        );
165                        foreground.timer(delay).await;
166                        delay_seconds = (delay_seconds * 2).min(300);
167                    }
168                }));
169            }
170            Status::Disconnected => {
171                state._maintain_connection.take();
172            }
173            _ => {}
174        }
175    }
176
177    pub fn subscribe_from_model<T, M, F>(
178        self: &Arc<Self>,
179        remote_id: u64,
180        cx: &mut ModelContext<M>,
181        mut handler: F,
182    ) -> Subscription
183    where
184        T: EntityMessage,
185        M: Entity,
186        F: 'static
187            + Send
188            + Sync
189            + FnMut(&mut M, TypedEnvelope<T>, Arc<Self>, &mut ModelContext<M>) -> Result<()>,
190    {
191        let subscription_id = (TypeId::of::<T>(), remote_id);
192        let client = self.clone();
193        let mut state = self.state.write();
194        let model = cx.handle().downgrade();
195        state
196            .entity_id_extractors
197            .entry(subscription_id.0)
198            .or_insert_with(|| {
199                Box::new(|envelope| {
200                    let envelope = envelope
201                        .as_any()
202                        .downcast_ref::<TypedEnvelope<T>>()
203                        .unwrap();
204                    envelope.payload.remote_entity_id()
205                })
206            });
207        let prev_handler = state.model_handlers.insert(
208            subscription_id,
209            Box::new(move |envelope, cx| {
210                if let Some(model) = model.upgrade(cx) {
211                    let envelope = envelope.into_any().downcast::<TypedEnvelope<T>>().unwrap();
212                    model.update(cx, |model, cx| {
213                        if let Err(error) = handler(model, *envelope, client.clone(), cx) {
214                            log::error!("error handling message: {}", error)
215                        }
216                    });
217                }
218            }),
219        );
220        if prev_handler.is_some() {
221            panic!("registered a handler for the same entity twice")
222        }
223
224        Subscription {
225            client: Arc::downgrade(self),
226            id: subscription_id,
227        }
228    }
229
230    pub async fn authenticate_and_connect(
231        self: &Arc<Self>,
232        cx: &AsyncAppContext,
233    ) -> anyhow::Result<()> {
234        let was_disconnected = match *self.status().borrow() {
235            Status::Disconnected => true,
236            Status::ConnectionError | Status::ConnectionLost | Status::ReconnectionError { .. } => {
237                false
238            }
239            Status::Connected { .. }
240            | Status::Connecting { .. }
241            | Status::Reconnecting { .. }
242            | Status::Authenticating
243            | Status::Reauthenticating => return Ok(()),
244        };
245
246        if was_disconnected {
247            self.set_status(Status::Authenticating, cx);
248        } else {
249            self.set_status(Status::Reauthenticating, cx)
250        }
251
252        let (user_id, access_token) = match self.authenticate(&cx).await {
253            Ok(result) => result,
254            Err(err) => {
255                self.set_status(Status::ConnectionError, cx);
256                return Err(err);
257            }
258        };
259
260        if was_disconnected {
261            self.set_status(Status::Connecting { user_id }, cx);
262        } else {
263            self.set_status(Status::Reconnecting { user_id }, cx);
264        }
265        match self.connect(user_id, &access_token, cx).await {
266            Ok(conn) => {
267                log::info!("connected to rpc address {}", *ZED_SERVER_URL);
268                self.set_connection(user_id, conn, cx).await;
269                Ok(())
270            }
271            Err(err) => {
272                self.set_status(Status::ConnectionError, cx);
273                Err(err)
274            }
275        }
276    }
277
278    async fn set_connection(self: &Arc<Self>, user_id: u64, conn: Conn, cx: &AsyncAppContext) {
279        let (connection_id, handle_io, mut incoming) = self.peer.add_connection(conn).await;
280        cx.foreground()
281            .spawn({
282                let mut cx = cx.clone();
283                let this = self.clone();
284                async move {
285                    while let Some(message) = incoming.recv().await {
286                        let mut state = this.state.write();
287                        if let Some(extract_entity_id) =
288                            state.entity_id_extractors.get(&message.payload_type_id())
289                        {
290                            let entity_id = (extract_entity_id)(message.as_ref());
291                            if let Some(handler) = state
292                                .model_handlers
293                                .get_mut(&(message.payload_type_id(), entity_id))
294                            {
295                                let start_time = Instant::now();
296                                log::info!("RPC client message {}", message.payload_type_name());
297                                (handler)(message, &mut cx);
298                                log::info!(
299                                    "RPC message handled. duration:{:?}",
300                                    start_time.elapsed()
301                                );
302                            } else {
303                                log::info!("unhandled message {}", message.payload_type_name());
304                            }
305                        } else {
306                            log::info!("unhandled message {}", message.payload_type_name());
307                        }
308                    }
309                }
310            })
311            .detach();
312
313        self.set_status(
314            Status::Connected {
315                connection_id,
316                user_id,
317            },
318            cx,
319        );
320
321        let handle_io = cx.background().spawn(handle_io);
322        let this = self.clone();
323        let cx = cx.clone();
324        cx.foreground()
325            .spawn(async move {
326                match handle_io.await {
327                    Ok(()) => this.set_status(Status::Disconnected, &cx),
328                    Err(err) => {
329                        log::error!("connection error: {:?}", err);
330                        this.set_status(Status::ConnectionLost, &cx);
331                    }
332                }
333            })
334            .detach();
335    }
336
337    fn authenticate(self: &Arc<Self>, cx: &AsyncAppContext) -> Task<Result<(u64, String)>> {
338        if let Some(callback) = self.auth_callback.as_ref() {
339            callback(cx)
340        } else {
341            self.authenticate_with_browser(cx)
342        }
343    }
344
345    fn connect(
346        self: &Arc<Self>,
347        user_id: u64,
348        access_token: &str,
349        cx: &AsyncAppContext,
350    ) -> Task<Result<Conn>> {
351        if let Some(callback) = self.connect_callback.as_ref() {
352            callback(user_id, access_token, cx)
353        } else {
354            self.connect_with_websocket(user_id, access_token, cx)
355        }
356    }
357
358    fn connect_with_websocket(
359        self: &Arc<Self>,
360        user_id: u64,
361        access_token: &str,
362        cx: &AsyncAppContext,
363    ) -> Task<Result<Conn>> {
364        let request =
365            Request::builder().header("Authorization", format!("{} {}", user_id, access_token));
366        cx.background().spawn(async move {
367            if let Some(host) = ZED_SERVER_URL.strip_prefix("https://") {
368                let stream = smol::net::TcpStream::connect(host).await?;
369                let request = request.uri(format!("wss://{}/rpc", host)).body(())?;
370                let (stream, _) = async_tungstenite::async_tls::client_async_tls(request, stream)
371                    .await
372                    .context("websocket handshake")?;
373                Ok(Conn::new(stream))
374            } else if let Some(host) = ZED_SERVER_URL.strip_prefix("http://") {
375                let stream = smol::net::TcpStream::connect(host).await?;
376                let request = request.uri(format!("ws://{}/rpc", host)).body(())?;
377                let (stream, _) = async_tungstenite::client_async(request, stream)
378                    .await
379                    .context("websocket handshake")?;
380                Ok(Conn::new(stream))
381            } else {
382                Err(anyhow!("invalid server url: {}", *ZED_SERVER_URL))
383            }
384        })
385    }
386
387    pub fn authenticate_with_browser(
388        self: &Arc<Self>,
389        cx: &AsyncAppContext,
390    ) -> Task<Result<(u64, String)>> {
391        let platform = cx.platform();
392        let executor = cx.background();
393        executor.clone().spawn(async move {
394            if let Some((user_id, access_token)) = platform
395                .read_credentials(&ZED_SERVER_URL)
396                .log_err()
397                .flatten()
398            {
399                log::info!("already signed in. user_id: {}", user_id);
400                return Ok((user_id.parse()?, String::from_utf8(access_token).unwrap()));
401            }
402
403            // Generate a pair of asymmetric encryption keys. The public key will be used by the
404            // zed server to encrypt the user's access token, so that it can'be intercepted by
405            // any other app running on the user's device.
406            let (public_key, private_key) =
407                zrpc::auth::keypair().expect("failed to generate keypair for auth");
408            let public_key_string =
409                String::try_from(public_key).expect("failed to serialize public key for auth");
410
411            // Start an HTTP server to receive the redirect from Zed's sign-in page.
412            let server = tiny_http::Server::http("127.0.0.1:0").expect("failed to find open port");
413            let port = server.server_addr().port();
414
415            // Open the Zed sign-in page in the user's browser, with query parameters that indicate
416            // that the user is signing in from a Zed app running on the same device.
417            platform.open_url(&format!(
418                "{}/sign_in?native_app_port={}&native_app_public_key={}",
419                *ZED_SERVER_URL, port, public_key_string
420            ));
421
422            // Receive the HTTP request from the user's browser. Retrieve the user id and encrypted
423            // access token from the query params.
424            //
425            // TODO - Avoid ever starting more than one HTTP server. Maybe switch to using a
426            // custom URL scheme instead of this local HTTP server.
427            let (user_id, access_token) = executor
428                .spawn(async move {
429                    if let Some(req) = server.recv_timeout(Duration::from_secs(10 * 60))? {
430                        let path = req.url();
431                        let mut user_id = None;
432                        let mut access_token = None;
433                        let url = Url::parse(&format!("http://example.com{}", path))
434                            .context("failed to parse login notification url")?;
435                        for (key, value) in url.query_pairs() {
436                            if key == "access_token" {
437                                access_token = Some(value.to_string());
438                            } else if key == "user_id" {
439                                user_id = Some(value.to_string());
440                            }
441                        }
442                        req.respond(
443                            tiny_http::Response::from_string(LOGIN_RESPONSE).with_header(
444                                tiny_http::Header::from_bytes("Content-Type", "text/html").unwrap(),
445                            ),
446                        )
447                        .context("failed to respond to login http request")?;
448                        Ok((
449                            user_id.ok_or_else(|| anyhow!("missing user_id parameter"))?,
450                            access_token
451                                .ok_or_else(|| anyhow!("missing access_token parameter"))?,
452                        ))
453                    } else {
454                        Err(anyhow!("didn't receive login redirect"))
455                    }
456                })
457                .await?;
458
459            let access_token = private_key
460                .decrypt_string(&access_token)
461                .context("failed to decrypt access token")?;
462            platform.activate(true);
463            platform
464                .write_credentials(&ZED_SERVER_URL, &user_id, access_token.as_bytes())
465                .log_err();
466            Ok((user_id.parse()?, access_token))
467        })
468    }
469
470    pub async fn disconnect(self: &Arc<Self>, cx: &AsyncAppContext) -> Result<()> {
471        let conn_id = self.connection_id()?;
472        self.peer.disconnect(conn_id).await;
473        self.set_status(Status::Disconnected, cx);
474        Ok(())
475    }
476
477    fn connection_id(&self) -> Result<ConnectionId> {
478        if let Status::Connected { connection_id, .. } = *self.status().borrow() {
479            Ok(connection_id)
480        } else {
481            Err(anyhow!("not connected"))
482        }
483    }
484
485    pub async fn send<T: EnvelopedMessage>(&self, message: T) -> Result<()> {
486        self.peer.send(self.connection_id()?, message).await
487    }
488
489    pub async fn request<T: RequestMessage>(&self, request: T) -> Result<T::Response> {
490        self.peer.request(self.connection_id()?, request).await
491    }
492
493    pub fn respond<T: RequestMessage>(
494        &self,
495        receipt: Receipt<T>,
496        response: T::Response,
497    ) -> impl Future<Output = Result<()>> {
498        self.peer.respond(receipt, response)
499    }
500}
501
502const WORKTREE_URL_PREFIX: &'static str = "zed://worktrees/";
503
504pub fn encode_worktree_url(id: u64, access_token: &str) -> String {
505    format!("{}{}/{}", WORKTREE_URL_PREFIX, id, access_token)
506}
507
508pub fn decode_worktree_url(url: &str) -> Option<(u64, String)> {
509    let path = url.trim().strip_prefix(WORKTREE_URL_PREFIX)?;
510    let mut parts = path.split('/');
511    let id = parts.next()?.parse::<u64>().ok()?;
512    let access_token = parts.next()?;
513    if access_token.is_empty() {
514        return None;
515    }
516    Some((id, access_token.to_string()))
517}
518
519const LOGIN_RESPONSE: &'static str = "
520<!DOCTYPE html>
521<html>
522<script>window.close();</script>
523</html>
524";
525
526#[cfg(test)]
527mod tests {
528    use super::*;
529    use crate::test::FakeServer;
530    use gpui::TestAppContext;
531
532    #[gpui::test(iterations = 10)]
533    async fn test_heartbeat(cx: TestAppContext) {
534        cx.foreground().forbid_parking();
535
536        let user_id = 5;
537        let mut client = Client::new();
538        let server = FakeServer::for_client(user_id, &mut client, &cx).await;
539
540        cx.foreground().advance_clock(Duration::from_secs(10));
541        let ping = server.receive::<proto::Ping>().await.unwrap();
542        assert_eq!(ping.payload.id, 0);
543        server.respond(ping.receipt(), proto::Pong { id: 0 }).await;
544
545        cx.foreground().advance_clock(Duration::from_secs(10));
546        let ping = server.receive::<proto::Ping>().await.unwrap();
547        assert_eq!(ping.payload.id, 1);
548        server.respond(ping.receipt(), proto::Pong { id: 1 }).await;
549
550        client.disconnect(&cx.to_async()).await.unwrap();
551        assert!(server.receive::<proto::Ping>().await.is_err());
552    }
553
554    #[gpui::test(iterations = 10)]
555    async fn test_reconnection(cx: TestAppContext) {
556        cx.foreground().forbid_parking();
557
558        let user_id = 5;
559        let mut client = Client::new();
560        let server = FakeServer::for_client(user_id, &mut client, &cx).await;
561        let mut status = client.status();
562        assert!(matches!(
563            status.recv().await,
564            Some(Status::Connected { .. })
565        ));
566
567        server.forbid_connections();
568        server.disconnect().await;
569        while !matches!(status.recv().await, Some(Status::ReconnectionError { .. })) {}
570
571        server.allow_connections();
572        cx.foreground().advance_clock(Duration::from_secs(10));
573        while !matches!(status.recv().await, Some(Status::Connected { .. })) {}
574    }
575
576    #[test]
577    fn test_encode_and_decode_worktree_url() {
578        let url = encode_worktree_url(5, "deadbeef");
579        assert_eq!(decode_worktree_url(&url), Some((5, "deadbeef".to_string())));
580        assert_eq!(
581            decode_worktree_url(&format!("\n {}\t", url)),
582            Some((5, "deadbeef".to_string()))
583        );
584        assert_eq!(decode_worktree_url("not://the-right-format"), None);
585    }
586}