From 89be0081aa3397d011c26ce2f6f349b605bf3fea Mon Sep 17 00:00:00 2001
From: Igor Solovey <igor.solovey@uwo.ca>
Date: Wed, 11 Sep 2024 16:39:31 -0400
Subject: [PATCH 1/2] Optimize multipart message decoding

Avoid repeated truncation/reallocation of a bytes array, and expensive call to split()
---
 src/dicomweb_client/web.py | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/dicomweb_client/web.py b/src/dicomweb_client/web.py
index 3b305a2..c420169 100644
--- a/src/dicomweb_client/web.py
+++ b/src/dicomweb_client/web.py
@@ -673,7 +673,7 @@ def _decode_multipart_message(
 
         marker = b''.join((b'--', boundary))
         delimiter = b''.join((b'\r\n', marker))
-        data = b''
+        data = bytearray()
         j = 0
         with response:
             logger.debug('decode message content')
@@ -685,16 +685,23 @@ def _decode_multipart_message(
                 if stream:
                     logger.debug(f'decode message content chunk #{i}')
                 data += chunk
-                while delimiter in data:
+
+                prev_part_index = 0
+                while (
+                        delimiter_index := data.find(delimiter, prev_part_index)
+                ) >= 0:
                     logger.debug(f'decode message part #{j}')
-                    part, data = data.split(delimiter, maxsplit=1)
-                    content = self._extract_part_content(part)
+                    content = self._extract_part_content(
+                        data[prev_part_index:delimiter_index]
+                    )
+                    prev_part_index = delimiter_index + len(delimiter)
                     j += 1
                     if content is not None:
                         logger.debug(
                             f'extracted {len(content)} bytes from part #{j}'
                         )
                         yield content
+                data = data[prev_part_index:]
 
         content = self._extract_part_content(data)
         if content is not None:

From f0b58c1a7ca97fc7ef3c9af5ebe1953be55c4012 Mon Sep 17 00:00:00 2001
From: Chris Bridge <chrisbridge44@googlemail.com>
Date: Sat, 19 Oct 2024 13:57:58 -0400
Subject: [PATCH 2/2] Remove walrus operator

---
 src/dicomweb_client/web.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/dicomweb_client/web.py b/src/dicomweb_client/web.py
index c420169..d7b96d2 100644
--- a/src/dicomweb_client/web.py
+++ b/src/dicomweb_client/web.py
@@ -687,9 +687,10 @@ def _decode_multipart_message(
                 data += chunk
 
                 prev_part_index = 0
-                while (
-                        delimiter_index := data.find(delimiter, prev_part_index)
-                ) >= 0:
+                while True:
+                    delimiter_index = data.find(delimiter, prev_part_index)
+                    if delimiter_index < 0:
+                        break
                     logger.debug(f'decode message part #{j}')
                     content = self._extract_part_content(
                         data[prev_part_index:delimiter_index]