Speeding up the protocol parsing (#2596)

* speeding up the protocol parser

* linting

* changes to ease

Author: chayim

redis/asyncio/connection.py

@@ -267,9 +267,6 @@ async def _read_response(
         response: Any
         byte, response = raw[:1], raw[1:]
 
-        if byte not in (b"-", b"+", b":", b"$", b"*"):
-            raise InvalidResponse(f"Protocol Error: {raw!r}")
-
         # server returned an error
         if byte == b"-":
             response = response.decode("utf-8", errors="replace")
@@ -289,22 +286,24 @@ async def _read_response(
             pass
         # int value
         elif byte == b":":
-            response = int(response)
+            return int(response)
         # bulk response
+        elif byte == b"$" and response == b"-1":
+            return None
         elif byte == b"$":
-            length = int(response)
-            if length == -1:
-                return None
-            response = await self._read(length)
+            response = await self._read(int(response))
         # multi-bulk response
+        elif byte == b"*" and response == b"-1":
+            return None
         elif byte == b"*":
-            length = int(response)
-            if length == -1:
-                return None
             response = [
-                (await self._read_response(disable_decoding)) for _ in range(length)
+                (await self._read_response(disable_decoding))
+                for _ in range(int(response))  # noqa
             ]
-        if isinstance(response, bytes) and disable_decoding is False:
+        else:
+            raise InvalidResponse(f"Protocol Error: {raw!r}")
+
+        if disable_decoding is False:
             response = self.encoder.decode(response)
         return response
 

redis/connection.py

@@ -358,9 +358,6 @@ def _read_response(self, disable_decoding=False):
 
         byte, response = raw[:1], raw[1:]
 
-        if byte not in (b"-", b"+", b":", b"$", b"*"):
-            raise InvalidResponse(f"Protocol Error: {raw!r}")
-
         # server returned an error
         if byte == b"-":
             response = response.decode("utf-8", errors="replace")
@@ -379,23 +376,24 @@ def _read_response(self, disable_decoding=False):
             pass
         # int value
         elif byte == b":":
-            response = int(response)
+            return int(response)
         # bulk response
+        elif byte == b"$" and response == b"-1":
+            return None
         elif byte == b"$":
-            length = int(response)
-            if length == -1:
-                return None
-            response = self._buffer.read(length)
+            response = self._buffer.read(int(response))
         # multi-bulk response
+        elif byte == b"*" and response == b"-1":
+            return None
         elif byte == b"*":
-            length = int(response)
-            if length == -1:
-                return None
             response = [
                 self._read_response(disable_decoding=disable_decoding)
-                for i in range(length)
+                for i in range(int(response))
             ]
-        if isinstance(response, bytes) and disable_decoding is False:
+        else:
+            raise InvalidResponse(f"Protocol Error: {raw!r}")
+
+        if disable_decoding is False:
             response = self.encoder.decode(response)
         return response