feat: Support backend socket connections (UDS)

src/stream.rs

@@ -0,0 +1,66 @@
+use tokio::io::{AsyncRead, AsyncWrite, ReadBuf};
+use tokio::net::{TcpStream, UnixStream};
+
+use std::io::Result;
+use std::marker::Unpin;
+use std::pin::{Pin, pin};
+use std::task::{Context, Poll};
+
+pub enum AbstractStream {
+    Tcp(TcpStream),
+    Uds(UnixStream),
+}
+
+impl From<TcpStream> for AbstractStream {
+    fn from(stream: TcpStream) -> Self {
+        Self::Tcp(stream)
+    }
+}
+
+impl From<UnixStream> for AbstractStream {
+    fn from(stream: UnixStream) -> Self {
+        Self::Uds(stream)
+    }
+}
+
+impl Unpin for AbstractStream {}
+
+impl AsyncRead for AbstractStream {
+    fn poll_read(
+        mut self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+        buf: &mut ReadBuf<'_>,
+    ) -> Poll<Result<()>> {
+        match &mut *self {
+            Self::Tcp(stream) => pin!(stream).poll_read(cx, buf),
+            Self::Uds(stream) => pin!(stream).poll_read(cx, buf),
+        }
+    }
+}
+
+impl AsyncWrite for AbstractStream {
+    fn poll_write(
+        mut self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+        buf: &[u8],
+    ) -> Poll<Result<usize>> {
+        match &mut *self {
+            Self::Tcp(stream) => pin!(stream).poll_write(cx, buf),
+            Self::Uds(stream) => pin!(stream).poll_write(cx, buf),
+        }
+    }
+
+    fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+        match &mut *self {
+            Self::Tcp(stream) => pin!(stream).poll_flush(cx),
+            Self::Uds(stream) => pin!(stream).poll_flush(cx),
+        }
+    }
+
+    fn poll_shutdown(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+        match &mut *self {
+            Self::Tcp(stream) => pin!(stream).poll_shutdown(cx),
+            Self::Uds(stream) => pin!(stream).poll_shutdown(cx),
+        }
+    }
+}