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);
 74request_message!(OpenBuffer, OpenBufferResponse);
 75message!(CloseBuffer);
 76message!(UpdateBuffer);
 77message!(AddGuest);
 78message!(RemoveGuest);
 79
 80/// A stream of protobuf messages.
 81pub struct MessageStream<T> {
 82    byte_stream: T,
 83    buffer: Vec<u8>,
 84}
 85
 86impl<T> MessageStream<T> {
 87    pub fn new(byte_stream: T) -> Self {
 88        Self {
 89            byte_stream,
 90            buffer: Default::default(),
 91        }
 92    }
 93
 94    pub fn inner_mut(&mut self) -> &mut T {
 95        &mut self.byte_stream
 96    }
 97}
 98
 99impl<T> MessageStream<T>
100where
101    T: AsyncWrite + Unpin,
102{
103    /// Write a given protobuf message to the stream.
104    pub async fn write_message(&mut self, message: &Envelope) -> io::Result<()> {
105        let message_len: u32 = message
106            .encoded_len()
107            .try_into()
108            .map_err(|_| io::Error::new(io::ErrorKind::InvalidData, "message is too large"))?;
109        self.buffer.clear();
110        self.buffer.extend_from_slice(&message_len.to_be_bytes());
111        message.encode(&mut self.buffer)?;
112        self.byte_stream.write_all(&self.buffer).await
113    }
114}
115
116impl<T> MessageStream<T>
117where
118    T: AsyncRead + Unpin,
119{
120    /// Read a protobuf message of the given type from the stream.
121    pub async fn read_message(&mut self) -> io::Result<Envelope> {
122        let mut delimiter_buf = [0; 4];
123        self.byte_stream.read_exact(&mut delimiter_buf).await?;
124        let message_len = u32::from_be_bytes(delimiter_buf) as usize;
125        self.buffer.resize(message_len, 0);
126        self.byte_stream.read_exact(&mut self.buffer).await?;
127        Ok(Envelope::decode(self.buffer.as_slice())?)
128    }
129}
130
131impl Into<SystemTime> for Timestamp {
132    fn into(self) -> SystemTime {
133        UNIX_EPOCH
134            .checked_add(Duration::new(self.seconds, self.nanos))
135            .unwrap()
136    }
137}
138
139impl From<SystemTime> for Timestamp {
140    fn from(time: SystemTime) -> Self {
141        let duration = time.duration_since(UNIX_EPOCH).unwrap();
142        Self {
143            seconds: duration.as_secs(),
144            nanos: duration.subsec_nanos(),
145        }
146    }
147}
148
149#[cfg(test)]
150mod tests {
151    use super::*;
152    use std::{
153        pin::Pin,
154        task::{Context, Poll},
155    };
156
157    #[test]
158    fn test_round_trip_message() {
159        smol::block_on(async {
160            let byte_stream = ChunkedStream {
161                bytes: Vec::new(),
162                read_offset: 0,
163                chunk_size: 3,
164            };
165
166            let message1 = Auth {
167                user_id: 5,
168                access_token: "the-access-token".into(),
169            }
170            .into_envelope(3, None, None);
171
172            let message2 = OpenBuffer {
173                worktree_id: 0,
174                path: "some/path".to_string(),
175            }
176            .into_envelope(5, None, None);
177
178            let mut message_stream = MessageStream::new(byte_stream);
179            message_stream.write_message(&message1).await.unwrap();
180            message_stream.write_message(&message2).await.unwrap();
181            let decoded_message1 = message_stream.read_message().await.unwrap();
182            let decoded_message2 = message_stream.read_message().await.unwrap();
183            assert_eq!(decoded_message1, message1);
184            assert_eq!(decoded_message2, message2);
185        });
186    }
187
188    struct ChunkedStream {
189        bytes: Vec<u8>,
190        read_offset: usize,
191        chunk_size: usize,
192    }
193
194    impl AsyncWrite for ChunkedStream {
195        fn poll_write(
196            mut self: Pin<&mut Self>,
197            _: &mut Context<'_>,
198            buf: &[u8],
199        ) -> Poll<io::Result<usize>> {
200            let bytes_written = buf.len().min(self.chunk_size);
201            self.bytes.extend_from_slice(&buf[0..bytes_written]);
202            Poll::Ready(Ok(bytes_written))
203        }
204
205        fn poll_flush(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
206            Poll::Ready(Ok(()))
207        }
208
209        fn poll_close(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
210            Poll::Ready(Ok(()))
211        }
212    }
213
214    impl AsyncRead for ChunkedStream {
215        fn poll_read(
216            mut self: Pin<&mut Self>,
217            _: &mut Context<'_>,
218            buf: &mut [u8],
219        ) -> Poll<io::Result<usize>> {
220            let bytes_read = buf
221                .len()
222                .min(self.chunk_size)
223                .min(self.bytes.len() - self.read_offset);
224            let end_offset = self.read_offset + bytes_read;
225            buf[0..bytes_read].copy_from_slice(&self.bytes[self.read_offset..end_offset]);
226            self.read_offset = end_offset;
227            Poll::Ready(Ok(bytes_read))
228        }
229    }
230}