feat(redis): add native JSON session storage for 4.1.0

- Add opt-in SESSION_REDIS_JSON storage for asyncio Redis backends.
- Check JSON command support at startup and reject JSON mode on Trio.
- Read legacy strings and migrate sessions on their next save.
- Validate JSON objects before transactional replacement and expiry.
- Preserve tagged serialization for datetime, tuple, and other types.
- Cover command contracts, error handling, and session round-trips.
- Document server requirements, permissions, and migration limits.
- Normalize indentation and whitespace across code, tests, and examples.
- Bump the package and lockfile to 4.1.0 and update the changelog.
- Refresh the locked pycparser dependency to 3.12.

quart_session/redis_trio/serialization.py

@@ -1,14 +1,14 @@
 # -*- coding: utf-8 -*-
 """
-    quart_session.redis_trio.serialization
-    ~~~~~~~~~~~~~~~~~~~~~~
+  quart_session.redis_trio.serialization
+  ~~~~~~~~~~~~~~~~~~~~~~
 
-    A simple Redis Trio client.
+  A simple Redis Trio client.
 
-    :copyright: (c) 2017 by Bogdan Paul Popa.
-    :copyright: (c) 2019 by Oleksii Aleksieiev.
-    :copyright: (c) 2020 by dsc.
-    :license: BSD, see LICENSE for more details.
+  :copyright: (c) 2017 by Bogdan Paul Popa.
+  :copyright: (c) 2019 by Oleksii Aleksieiev.
+  :copyright: (c) 2020 by dsc.
+  :license: BSD, see LICENSE for more details.
 """
 
 from collections import namedtuple
@@ -19,42 +19,39 @@ atom = namedtuple("atom", ("value",))
 #: The set of characters that must be escaped before being sent as
 #: Redis strings.
 escapes = {
-    ord(b"\0"): rb"\x00",
-    ord(b"\n"): rb"\n",
-    ord(b"\r"): rb"\r",
-    ord(b"\\"): rb"\\",
-    ord(b'"'): rb'\"',
+  ord(b"\0"): rb"\x00",
+  ord(b"\n"): rb"\n",
+  ord(b"\r"): rb"\r",
+  ord(b"\\"): rb"\\",
+  ord(b'"'): rb'\"',
 }
 
-
 def serialize(x):
-    """Serialize `x` so that it can safely be sent to Redis.
+  """Serialize `x` so that it can safely be sent to Redis.
 
-    Parameters:
-      x(object): The value to serialize.
-
-    Returns:
-      bytes: The serialized value.
-    """
-    if isinstance(x, atom):
-        return x.value
-    elif isinstance(x, bytes):
-        return quote(x)
-    elif isinstance(x, str):
-        return quote(x.encode("utf-8"))
-    elif isinstance(x, (float, int)):
-        return str(x).encode("ascii")
-    else:
-        return serialize(str(x))
+  Parameters:
+    x(object): The value to serialize.
 
+  Returns:
+    bytes: The serialized value.
+  """
+  if isinstance(x, atom):
+    return x.value
+  elif isinstance(x, bytes):
+    return quote(x)
+  elif isinstance(x, str):
+    return quote(x.encode("utf-8"))
+  elif isinstance(x, (float, int)):
+    return str(x).encode("ascii")
+  else:
+    return serialize(str(x))
 
 def quote(bs):
-    return b'"' + bytes(escape(bs)) + b'"'
-
+  return b'"' + bytes(escape(bs)) + b'"'
 
 def escape(bs):
-    for c in bs:
-        if c in escapes:
-            yield from escapes[c]
-        else:
-            yield c
+  for c in bs:
+    if c in escapes:
+      yield from escapes[c]
+    else:
+      yield c