proto.rs

  1use futures::io::{AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt as _};
  2use prost::Message;
  3use std::{
  4    convert::TryInto,
  5    io,
  6    time::{Duration, SystemTime, UNIX_EPOCH},
  7};
  8
  9include!(concat!(env!("OUT_DIR"), "/zed.messages.rs"));
 10
 11pub trait EnvelopedMessage: Sized + Send + 'static {
 12    const NAME: &'static str;
 13    fn into_envelope(
 14        self,
 15        id: u32,
 16        responding_to: Option<u32>,
 17        original_sender_id: Option<u32>,
 18    ) -> Envelope;
 19    fn matches_envelope(envelope: &Envelope) -> bool;
 20    fn from_envelope(envelope: Envelope) -> Option<Self>;
 21}
 22
 23pub trait RequestMessage: EnvelopedMessage {
 24    type Response: EnvelopedMessage;
 25}
 26
 27macro_rules! message {
 28    ($name:ident) => {
 29        impl EnvelopedMessage for $name {
 30            const NAME: &'static str = std::stringify!($name);
 31
 32            fn into_envelope(
 33                self,
 34                id: u32,
 35                responding_to: Option<u32>,
 36                original_sender_id: Option<u32>,
 37            ) -> Envelope {
 38                Envelope {
 39                    id,
 40                    responding_to,
 41                    original_sender_id,
 42                    payload: Some(envelope::Payload::$name(self)),
 43                }
 44            }
 45
 46            fn matches_envelope(envelope: &Envelope) -> bool {
 47                matches!(&envelope.payload, Some(envelope::Payload::$name(_)))
 48            }
 49
 50            fn from_envelope(envelope: Envelope) -> Option<Self> {
 51                if let Some(envelope::Payload::$name(msg)) = envelope.payload {
 52                    Some(msg)
 53                } else {
 54                    None
 55                }
 56            }
 57        }
 58    };
 59}
 60
 61macro_rules! request_message {
 62    ($req:ident, $resp:ident) => {
 63        message!($req);
 64        message!($resp);
 65        impl RequestMessage for $req {
 66            type Response = $resp;
 67        }
 68    };
 69}
 70
 71request_message!(Auth, AuthResponse);
 72request_message!(ShareWorktree, ShareWorktreeResponse);
 73request_message!(OpenWorktree, OpenWorktreeResponse);
 74message!(CloseWorktree);
 75request_message!(OpenBuffer, OpenBufferResponse);
 76message!(CloseBuffer);
 77message!(UpdateBuffer);
 78message!(AddGuest);
 79message!(RemoveGuest);
 80
 81/// A stream of protobuf messages.
 82pub struct MessageStream<T> {
 83    byte_stream: T,
 84    buffer: Vec<u8>,
 85}
 86
 87impl<T> MessageStream<T> {
 88    pub fn new(byte_stream: T) -> Self {
 89        Self {
 90            byte_stream,
 91            buffer: Default::default(),
 92        }
 93    }
 94
 95    pub fn inner_mut(&mut self) -> &mut T {
 96        &mut self.byte_stream
 97    }
 98}
 99
100impl<T> MessageStream<T>
101where
102    T: AsyncWrite + Unpin,
103{
104    /// Write a given protobuf message to the stream.
105    pub async fn write_message(&mut self, message: &Envelope) -> io::Result<()> {
106        let message_len: u32 = message
107            .encoded_len()
108            .try_into()
109            .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "message is too large"))?;
110        self.buffer.clear();
111        self.buffer.extend_from_slice(&message_len.to_be_bytes());
112        message.encode(&mut self.buffer)?;
113        self.byte_stream.write_all(&self.buffer).await
114    }
115}
116
117impl<T> MessageStream<T>
118where
119    T: AsyncRead + Unpin,
120{
121    /// Read a protobuf message of the given type from the stream.
122    pub async fn read_message(&mut self) -> io::Result<Envelope> {
123        let mut delimiter_buf = [0; 4];
124        self.byte_stream.read_exact(&mut delimiter_buf).await?;
125        let message_len = u32::from_be_bytes(delimiter_buf) as usize;
126        self.buffer.resize(message_len, 0);
127        self.byte_stream.read_exact(&mut self.buffer).await?;
128        Ok(Envelope::decode(self.buffer.as_slice())?)
129    }
130}
131
132impl Into<SystemTime> for Timestamp {
133    fn into(self) -> SystemTime {
134        UNIX_EPOCH
135            .checked_add(Duration::new(self.seconds, self.nanos))
136            .unwrap()
137    }
138}
139
140impl From<SystemTime> for Timestamp {
141    fn from(time: SystemTime) -> Self {
142        let duration = time.duration_since(UNIX_EPOCH).unwrap();
143        Self {
144            seconds: duration.as_secs(),
145            nanos: duration.subsec_nanos(),
146        }
147    }
148}
149
150#[cfg(test)]
151mod tests {
152    use super::*;
153    use std::{
154        pin::Pin,
155        task::{Context, Poll},
156    };
157
158    #[test]
159    fn test_round_trip_message() {
160        smol::block_on(async {
161            let byte_stream = ChunkedStream {
162                bytes: Vec::new(),
163                read_offset: 0,
164                chunk_size: 3,
165            };
166
167            let message1 = Auth {
168                user_id: 5,
169                access_token: "the-access-token".into(),
170            }
171            .into_envelope(3, None, None);
172
173            let message2 = OpenBuffer {
174                worktree_id: 0,
175                path: "some/path".to_string(),
176            }
177            .into_envelope(5, None, None);
178
179            let mut message_stream = MessageStream::new(byte_stream);
180            message_stream.write_message(&message1).await.unwrap();
181            message_stream.write_message(&message2).await.unwrap();
182            let decoded_message1 = message_stream.read_message().await.unwrap();
183            let decoded_message2 = message_stream.read_message().await.unwrap();
184            assert_eq!(decoded_message1, message1);
185            assert_eq!(decoded_message2, message2);
186        });
187    }
188
189    struct ChunkedStream {
190        bytes: Vec<u8>,
191        read_offset: usize,
192        chunk_size: usize,
193    }
194
195    impl AsyncWrite for ChunkedStream {
196        fn poll_write(
197            mut self: Pin<&mut Self>,
198            _: &mut Context<'_>,
199            buf: &[u8],
200        ) -> Poll<io::Result<usize>> {
201            let bytes_written = buf.len().min(self.chunk_size);
202            self.bytes.extend_from_slice(&buf[0..bytes_written]);
203            Poll::Ready(Ok(bytes_written))
204        }
205
206        fn poll_flush(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
207            Poll::Ready(Ok(()))
208        }
209
210        fn poll_close(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
211            Poll::Ready(Ok(()))
212        }
213    }
214
215    impl AsyncRead for ChunkedStream {
216        fn poll_read(
217            mut self: Pin<&mut Self>,
218            _: &mut Context<'_>,
219            buf: &mut [u8],
220        ) -> Poll<io::Result<usize>> {
221            let bytes_read = buf
222                .len()
223                .min(self.chunk_size)
224                .min(self.bytes.len() - self.read_offset);
225            let end_offset = self.read_offset + bytes_read;
226            buf[0..bytes_read].copy_from_slice(&self.bytes[self.read_offset..end_offset]);
227            self.read_offset = end_offset;
228            Poll::Ready(Ok(bytes_read))
229        }
230    }
231}