Allow sending raw bytes in the response

We now only encode the body if it has an encode method, which usually
means it's a string. This allows passing bytes, bytearray or memoryview.

I also changed the logic for sending a chunk, that avoids copying the
data unnecessarily. I believe this also fixes a bug, where the size of
unencoded chunk was sent, in characters, instead of encoded size, in
bytes.

Author: deshipu

adafruit_httpserver/response.py

@@ -155,7 +155,10 @@ def send(
         if self._response_already_sent:
             raise RuntimeError("Response was already sent")
 
-        encoded_response_message_body = body.encode("utf-8")
+        if getattr(body, "encode", None):
+            encoded_response_message_body = body.encode("utf-8")
+        else:
+            encoded_response_message_body = body
 
         self._send_headers(
             content_type=content_type or self.content_type,
@@ -206,11 +209,12 @@ def send_chunk(self, chunk: str = "") -> None:
 
         :param str chunk: String data to be sent.
         """
-        hex_length = hex(len(chunk))[2:]  # removing 0x
+        if getattr(chunk, "encode", None):
+            chunk = chunk.encode("utf-8")
 
-        self._send_bytes(
-            self.request.connection, f"{hex_length}\r\n{chunk}\r\n".encode("utf-8")
-        )
+        self._send_bytes(self.request.connection, b"%x\r\n" % len(chunk))
+        self._send_bytes(self.request.connection, chunk)
+        self._send_bytes(self.request.connection, b"\r\n")
 
     def __enter__(self):
         if self.chunked: