From 9017efc7beb5e74bfcba32bf40386d4ff682c4e1 Mon Sep 17 00:00:00 2001
From: "Mike A." <git@mikealmel.ooo>
Date: Sun, 3 Aug 2025 21:42:08 +0200
Subject: [PATCH] refactor: specialize `Serializable` subclasses for stronger
 type safety

---
 findmy/accessory.py        |  2 +-
 findmy/keys.py             |  2 +-
 findmy/reports/account.py  |  2 +-
 findmy/reports/anisette.py |  4 ++--
 findmy/reports/reports.py  |  2 +-
 findmy/util/abc.py         | 11 ++++++-----
 6 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/findmy/accessory.py b/findmy/accessory.py
index 2082165..544170a 100644
--- a/findmy/accessory.py
+++ b/findmy/accessory.py
@@ -82,7 +82,7 @@ class RollingKeyPairSource(ABC):
         return keys
 
 
-class FindMyAccessory(RollingKeyPairSource, Serializable):
+class FindMyAccessory(RollingKeyPairSource, Serializable[FindMyAccessoryMapping]):
     """A findable Find My-accessory using official key rollover."""
 
     def __init__(  # noqa: PLR0913
diff --git a/findmy/keys.py b/findmy/keys.py
index 0db2f6b..76b849f 100644
--- a/findmy/keys.py
+++ b/findmy/keys.py
@@ -127,7 +127,7 @@ class HasPublicKey(HasHashedPublicKey, ABC):
         )
 
 
-class KeyPair(HasPublicKey, Serializable):
+class KeyPair(HasPublicKey, Serializable[KeyPairMapping]):
     """A private-public keypair for a trackable FindMy accessory."""
 
     def __init__(
diff --git a/findmy/reports/account.py b/findmy/reports/account.py
index 0d7460a..343bcfd 100644
--- a/findmy/reports/account.py
+++ b/findmy/reports/account.py
@@ -141,7 +141,7 @@ def _extract_phone_numbers(html: str) -> list[dict]:
     return data.get("direct", {}).get("phoneNumberVerification", {}).get("trustedPhoneNumbers", [])
 
 
-class BaseAppleAccount(Closable, Serializable, ABC):
+class BaseAppleAccount(Closable, Serializable[AccountStateMapping], ABC):
     """Base class for an Apple account."""
 
     @property
diff --git a/findmy/reports/anisette.py b/findmy/reports/anisette.py
index 2fb0f87..3c5efaf 100644
--- a/findmy/reports/anisette.py
+++ b/findmy/reports/anisette.py
@@ -188,7 +188,7 @@ class BaseAnisetteProvider(Closable, Serializable, ABC):
         return cpd
 
 
-class RemoteAnisetteProvider(BaseAnisetteProvider):
+class RemoteAnisetteProvider(BaseAnisetteProvider, Serializable[RemoteAnisetteMapping]):
     """Anisette provider. Fetches headers from a remote Anisette server."""
 
     _ANISETTE_DATA_VALID_FOR = 30
@@ -269,7 +269,7 @@ class RemoteAnisetteProvider(BaseAnisetteProvider):
         await self._http.close()
 
 
-class LocalAnisetteProvider(BaseAnisetteProvider):
+class LocalAnisetteProvider(BaseAnisetteProvider, Serializable[LocalAnisetteMapping]):
     """Anisette provider. Generates headers without a remote server using the `anisette` library."""
 
     def __init__(
diff --git a/findmy/reports/reports.py b/findmy/reports/reports.py
index cd3dd59..68c97f3 100644
--- a/findmy/reports/reports.py
+++ b/findmy/reports/reports.py
@@ -51,7 +51,7 @@ class LocationReportDecryptedMapping(TypedDict):
 LocationReportMapping = Union[LocationReportEncryptedMapping, LocationReportDecryptedMapping]
 
 
-class LocationReport(HasHashedPublicKey, Serializable):
+class LocationReport(HasHashedPublicKey, Serializable[LocationReportMapping]):
     """Location report corresponding to a certain `HasHashedPublicKey`."""
 
     def __init__(
diff --git a/findmy/util/abc.py b/findmy/util/abc.py
index 7b77d3e..a88da3b 100644
--- a/findmy/util/abc.py
+++ b/findmy/util/abc.py
@@ -5,12 +5,13 @@ from __future__ import annotations
 import asyncio
 import logging
 from abc import ABC, abstractmethod
+from collections.abc import Mapping
 from typing import TYPE_CHECKING, Generic, Self, TypeVar
 
 if TYPE_CHECKING:
     from pathlib import Path
 
-logging.getLogger(__name__)
+logger = logging.getLogger(__name__)
 
 
 class Closable(ABC):
@@ -42,14 +43,14 @@ class Closable(ABC):
             pass
 
 
-T = TypeVar("T", bound=dict)
+_T = TypeVar("_T", bound=Mapping)
 
 
-class Serializable(Generic[T], ABC):
+class Serializable(Generic[_T], ABC):
     """ABC for serializable classes."""
 
     @abstractmethod
-    def to_json(self, dst: str | Path | None = None, /) -> T:
+    def to_json(self, dst: str | Path | None = None, /) -> _T:
         """
         Export the current state of the object as a JSON-serializable dictionary.
 
@@ -66,7 +67,7 @@ class Serializable(Generic[T], ABC):
 
     @classmethod
     @abstractmethod
-    def from_json(cls, val: str | Path | T, /) -> Self:
+    def from_json(cls, val: str | Path | _T, /) -> Self:
         """
         Restore state from a previous `Closable.to_json` export.