Standardize uuid generation for events/storage/registry (#39184)

homeassistant/config_entries.py

@@ -4,7 +4,6 @@ import functools
 import logging
 from types import MappingProxyType
 from typing import Any, Callable, Dict, List, Optional, Set, Union, cast
-import uuid
 import weakref
 
 import attr
@@ -16,6 +15,7 @@ from homeassistant.helpers import entity_registry
 from homeassistant.helpers.event import Event
 from homeassistant.setup import async_process_deps_reqs, async_setup_component
 from homeassistant.util.decorator import Registry
+import homeassistant.util.uuid as uuid_util
 
 _LOGGER = logging.getLogger(__name__)
 _UNDEF: dict = {}
@@ -135,7 +135,7 @@ class ConfigEntry:
     ) -> None:
         """Initialize a config entry."""
         # Unique id of the config entry
-        self.entry_id = entry_id or uuid.uuid4().hex
+        self.entry_id = entry_id or uuid_util.uuid_v1mc_hex()
 
         # Version of the configuration.
         self.version = version

homeassistant/core.py

@@ -12,7 +12,6 @@ from ipaddress import ip_address
 import logging
 import os
 import pathlib
-import random
 import re
 import threading
 from time import monotonic
@@ -33,7 +32,6 @@ from typing import (
     Union,
     cast,
 )
-import uuid
 
 import attr
 import voluptuous as vol
@@ -77,6 +75,7 @@ import homeassistant.util.dt as dt_util
 from homeassistant.util.thread import fix_threading_exception_logging
 from homeassistant.util.timeout import TimeoutManager
 from homeassistant.util.unit_system import IMPERIAL_SYSTEM, METRIC_SYSTEM, UnitSystem
+import homeassistant.util.uuid as uuid_util
 
 # Typing imports that create a circular dependency
 if TYPE_CHECKING:
@@ -510,13 +509,7 @@ class Context:
 
     user_id: str = attr.ib(default=None)
     parent_id: Optional[str] = attr.ib(default=None)
-    # The uuid1 uses a random multicast MAC address instead of the real MAC address
-    # of the machine without the overhead of calling the getrandom() system call.
-    #
-    # This is effectively equivalent to PostgreSQL's uuid_generate_v1mc() function
-    id: str = attr.ib(
-        factory=lambda: uuid.uuid1(node=random.getrandbits(48) | (1 << 40)).hex
-    )
+    id: str = attr.ib(factory=uuid_util.uuid_v1mc_hex)
 
     def as_dict(self) -> dict:
         """Return a dictionary representation of the context."""

homeassistant/helpers/area_registry.py

@@ -3,12 +3,12 @@ from asyncio import Event
 from collections import OrderedDict
 import logging
 from typing import Dict, Iterable, List, MutableMapping, Optional, cast
-import uuid
 
 import attr
 
 from homeassistant.core import callback
 from homeassistant.loader import bind_hass
+import homeassistant.util.uuid as uuid_util
 
 from .typing import HomeAssistantType
 
@@ -26,7 +26,7 @@ class AreaEntry:
     """Area Registry Entry."""
 
     name: Optional[str] = attr.ib(default=None)
-    id: str = attr.ib(factory=lambda: uuid.uuid4().hex)
+    id: str = attr.ib(factory=uuid_util.uuid_v1mc_hex)
 
 
 class AreaRegistry:

homeassistant/helpers/device_registry.py

@@ -2,12 +2,12 @@
 from collections import OrderedDict
 import logging
 from typing import TYPE_CHECKING, Any, Dict, List, Optional, Set, Tuple, Union
-import uuid
 
 import attr
 
 from homeassistant.const import EVENT_HOMEASSISTANT_STARTED
 from homeassistant.core import Event, callback
+import homeassistant.util.uuid as uuid_util
 
 from .debounce import Debouncer
 from .singleton import singleton
@@ -73,7 +73,7 @@ class DeviceEntry:
     area_id: str = attr.ib(default=None)
     name_by_user: str = attr.ib(default=None)
     entry_type: str = attr.ib(default=None)
-    id: str = attr.ib(factory=lambda: uuid.uuid4().hex)
+    id: str = attr.ib(factory=uuid_util.uuid_v1mc_hex)
     # This value is not stored, just used to keep track of events to fire.
     is_new: bool = attr.ib(default=False)
 

homeassistant/util/uuid.py

@@ -0,0 +1,15 @@
+"""Helpers to generate uuids."""
+
+import random
+import uuid
+
+
+def uuid_v1mc_hex() -> str:
+    """Generate a uuid1 with a random multicast MAC address.
+
+    The uuid1 uses a random multicast MAC address instead of the real MAC address
+    of the machine without the overhead of calling the getrandom() system call.
+
+    This is effectively equivalent to PostgreSQL's uuid_generate_v1mc() function
+    """
+    return uuid.uuid1(node=random.getrandbits(48) | (1 << 40)).hex

tests/util/test_uuid.py

@@ -0,0 +1,11 @@
+"""Test Home Assistant uuid util methods."""
+
+import uuid
+
+import homeassistant.util.uuid as uuid_util
+
+
+async def test_uuid_v1mc_hex():
+    """Verify we can generate a uuid_v1mc and return hex."""
+    assert len(uuid_util.uuid_v1mc_hex()) == 32
+    assert uuid.UUID(uuid_util.uuid_v1mc_hex())