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