Update app_client_blocking.py - using mutable bytearray type as receiving buffer so that the buffer content can be modified inside a method read_to_buffer for DRY. This is equivalent to passing a reference in C/C++ language.

app_client_blocking.py

@@ -94,24 +94,22 @@ def main():
     print(f"sending request {repr(message)} to {addr}")
     sock.sendall(message)
 
-    _recv_buffer = b""
+    _recv_buffer = bytearray(b"")
+    def read_to_buffer(sock, length, buf : bytearray):
+        while len(buf) < length:
+            data = sock.recv(4096)
+            buf += data
 
     # read and process protoheader (fixed length of 2 byte in network order)
-    _jsonheader_len = None
     hdrlen = 2
-    while len(_recv_buffer) < hdrlen:
+    read_to_buffer(sock, hdrlen, _recv_buffer)
-        data = sock.recv(4096)
-        _recv_buffer += data
 
     # process_protoheader()
     _jsonheader_len = struct.unpack(">H", _recv_buffer[:hdrlen])[0]
     _recv_buffer = _recv_buffer[hdrlen:]
 
     # read and process jsonheader
-    jsonheader = None
+    read_to_buffer(sock, _jsonheader_len, _recv_buffer)
-    while len(_recv_buffer) < _jsonheader_len:
-        data = sock.recv(4096)
-        _recv_buffer += data
 
     # process_jsonheader()
     jsonheader = _json_decode(_recv_buffer[:_jsonheader_len], "utf-8")
@@ -126,11 +124,8 @@ def main():
             raise ValueError(f'Missing required header "{reqhdr}".')
 
     # read and process response
-    response = None
     content_len = jsonheader["content-length"]
-    while len(_recv_buffer) < content_len:
+    read_to_buffer(sock, content_len, _recv_buffer)
-        data = sock.recv(4096)
-        _recv_buffer += data
 
     # process_response():
     data = _recv_buffer[:content_len]