From 98f499e66216765a3b3fb47cffe3a305b242f1da Mon Sep 17 00:00:00 2001
From: Jixiang Jiang <jixiang@estuary.dev>
Date: Sun, 20 Mar 2022 14:12:56 -0400
Subject: [PATCH] tweaks

---
 crates/connector_proxy/src/libs/command.rs |  2 +-
 crates/connector_proxy/src/libs/stream.rs  | 17 ++++++-----------
 crates/connector_proxy/src/main.rs         | 10 +++++++---
 3 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/crates/connector_proxy/src/libs/command.rs b/crates/connector_proxy/src/libs/command.rs
index 1981577dbe..2ad0960595 100644
--- a/crates/connector_proxy/src/libs/command.rs
+++ b/crates/connector_proxy/src/libs/command.rs
@@ -1,4 +1,4 @@
-use crate::errors::{raise_custom_error, Error};
+use crate::errors::Error;
 
 use serde::{Deserialize, Serialize};
 use std::io::Write;
diff --git a/crates/connector_proxy/src/libs/stream.rs b/crates/connector_proxy/src/libs/stream.rs
index 5b9f533048..33d1e441e4 100644
--- a/crates/connector_proxy/src/libs/stream.rs
+++ b/crates/connector_proxy/src/libs/stream.rs
@@ -46,12 +46,11 @@ pub fn stream_all_airbyte_messages(
                     raise_custom_error(&format!("error in reading next in_stream: {:?}", e))?;
                 }
             }
-            let buf_split = buf.split();
-            let chunk = buf_split.chunk();
 
+            let chunk = buf.chunk();
             let deserializer = Deserializer::from_slice(&chunk);
 
-            // Deserialize to Value first, to avoid missing 'is_eof' signals in error.
+            // Deserialize to Value first, instead of Message, to avoid missing 'is_eof' signals in error.
             let mut value_stream = deserializer.into_iter::<Value>();
             while let Some(value) = value_stream.next() {
                 match value {
@@ -77,18 +76,14 @@ pub fn stream_all_airbyte_messages(
                 }
             }
 
-            // TODO(Jixiang): Improve efficiency here.
-            // There are unnecessary copying activities in and out from the buf, especially for large messages that spans multiple
-            // bytes messages in the stream. Ideally, we could both write and read from the same buf. However, both reading and writing
-            // from the same buf is not recommended, which yields warning of https://github.com/rust-lang/rust/issues/59159.
-            let remaining = &chunk[value_stream.byte_offset()..];
-            buf.extend_from_slice(remaining);
+            let byte_offset = value_stream.byte_offset();
+            drop(buf.split_to(byte_offset));
         }
 
         if buf.len() > 0 {
-            raise_custom_error("unconsumed content in stream found!")?;
+            raise_custom_error("unconsumed content in stream found.")?;
         }
 
-        tracing::info!("done reading all in_stream");
+        tracing::info!("done reading all in_stream.");
     }
 }
diff --git a/crates/connector_proxy/src/main.rs b/crates/connector_proxy/src/main.rs
index f835fe8108..b38c9550b7 100644
--- a/crates/connector_proxy/src/main.rs
+++ b/crates/connector_proxy/src/main.rs
@@ -10,7 +10,6 @@ use clap::{ArgEnum, Parser, Subcommand};
 use tokio::{
     io::AsyncReadExt,
     signal::unix::{signal, SignalKind},
-    time::timeout,
 };
 
 use apis::{FlowCaptureOperation, FlowMaterializeOperation, FlowRuntimeProtocol};
@@ -201,12 +200,17 @@ async fn delayed_execute(command_config_path: String) -> Result<(), Error> {
     match check_exit_status("delayed process", child.wait().await) {
         Err(e) => {
             let mut buf = Vec::new();
-            child.stderr.take().unwrap().read_to_end(&mut buf).await?;
+            child
+                .stderr
+                .take()
+                .ok_or(Error::MissingIOPipe)?
+                .read_to_end(&mut buf)
+                .await?;
 
             tracing::error!(
                 "connector failed. command_config: {:?}. stderr from connector: {}",
                 &command_config,
-                std::str::from_utf8(&buf).unwrap()
+                std::str::from_utf8(&buf).expect("error when decoding stderr")
             );
             Err(e)
         }