Move misc minor utils to a separate module

14 files changed, 69 insertions, 71 deletions

diff --git a/requests_cache/__init__.py b/requests_cache/__init__.py
index 2b53921..5f74a1f 100644
--- a/requests_cache/__init__.py
+++ b/requests_cache/__init__.py
@@ -1,44 +1,12 @@
 # flake8: noqa: E402,F401
 from logging import getLogger
-from typing import Callable, Iterable, Dict
 
-logger = getLogger(__name__)
+logger = getLogger('requests_cache')
 
 # Version is defined in pyproject.toml.
 # It's copied here to make it easier for client code to check the installed version.
 __version__ = '0.9.0'
 
-
-def get_placeholder_class(original_exception: Exception = None):
-    """Create a placeholder type for a class that does not have dependencies installed.
-    This allows delaying ImportErrors until init time, rather than at import time.
-    """
-    msg = 'Dependencies are not installed for this feature'
-
-    def _log_error():
-        logger.error(msg)
-        raise original_exception or ImportError(msg)
-
-    class Placeholder:
-        def __init__(self, *args, **kwargs):
-            _log_error()
-
-        def __getattr__(self, *args, **kwargs):
-            _log_error()
-
-        def dumps(self, *args, **kwargs):
-            _log_error()
-
-    return Placeholder
-
-
-def get_valid_kwargs(func: Callable, kwargs: Dict, extras: Iterable[str] = None) -> Dict:
-    """Get the subset of non-None ``kwargs`` that are valid params for ``func``"""
-    params = list(signature(func).parameters)
-    params.extend(extras or [])
-    return {k: v for k, v in kwargs.items() if k in params and v is not None}
-
-
 try:
     from .backends import *
     from .cache_control import *
diff --git a/requests_cache/_utils.py b/requests_cache/_utils.py
new file mode 100644
index 0000000..b3dfaee
--- /dev/null
+++ b/requests_cache/_utils.py
@@ -0,0 +1,48 @@
+"""Miscellaneous minor utility functions that don't really belong anywhere else"""
+from inspect import signature
+from logging import getLogger
+from typing import Any, Callable, Dict, Iterable, Iterator, List
+
+logger = getLogger('requests_cache')
+
+
+def chunkify(iterable: Iterable, max_size: int) -> Iterator[List]:
+    """Split an iterable into chunks of a max size"""
+    iterable = list(iterable)
+    for index in range(0, len(iterable), max_size):
+        yield iterable[index : index + max_size]
+
+
+def coalesce(*values: Any, default=None) -> Any:
+    """Get the first non-``None`` value in a list of values"""
+    return next((v for v in values if v is not None), default)
+
+
+def get_placeholder_class(original_exception: Exception = None):
+    """Create a placeholder type for a class that does not have dependencies installed.
+    This allows delaying ImportErrors until init time, rather than at import time.
+    """
+    msg = 'Dependencies are not installed for this feature'
+
+    def _log_error():
+        logger.error(msg)
+        raise original_exception or ImportError(msg)
+
+    class Placeholder:
+        def __init__(self, *args, **kwargs):
+            _log_error()
+
+        def __getattr__(self, *args, **kwargs):
+            _log_error()
+
+        def dumps(self, *args, **kwargs):
+            _log_error()
+
+    return Placeholder
+
+
+def get_valid_kwargs(func: Callable, kwargs: Dict, extras: Iterable[str] = None) -> Dict:
+    """Get the subset of non-None ``kwargs`` that are valid params for ``func``"""
+    params = list(signature(func).parameters)
+    params.extend(extras or [])
+    return {k: v for k, v in kwargs.items() if k in params and v is not None}
diff --git a/requests_cache/backends/__init__.py b/requests_cache/backends/__init__.py
index 69fca59..bc921f7 100644
--- a/requests_cache/backends/__init__.py
+++ b/requests_cache/backends/__init__.py
@@ -1,10 +1,9 @@
 """Classes and functions for cache persistence. See :ref:`backends` for general usage info."""
 # flake8: noqa: F401
-from inspect import signature
 from logging import getLogger
 from typing import Callable, Dict, Iterable, Optional, Type, Union
 
-from .. import get_placeholder_class, get_valid_kwargs
+from .._utils import get_placeholder_class
 from .base import BaseCache, BaseStorage, DictStorage
 
 # Backend-specific keyword arguments equivalent to 'cache_name'
diff --git a/requests_cache/backends/dynamodb.py b/requests_cache/backends/dynamodb.py
index 98ff6fa..e1a6089 100644
--- a/requests_cache/backends/dynamodb.py
+++ b/requests_cache/backends/dynamodb.py
@@ -49,7 +49,8 @@ from boto3.dynamodb.types import Binary
 from boto3.resources.base import ServiceResource
 from botocore.exceptions import ClientError
 
-from . import BaseCache, BaseStorage, get_valid_kwargs
+from .._utils import get_valid_kwargs
+from . import BaseCache, BaseStorage
 
 
 class DynamoDbCache(BaseCache):
diff --git a/requests_cache/backends/gridfs.py b/requests_cache/backends/gridfs.py
index 09aa360..ca370f6 100644
--- a/requests_cache/backends/gridfs.py
+++ b/requests_cache/backends/gridfs.py
@@ -14,7 +14,7 @@ API Reference
 from gridfs import GridFS
 from pymongo import MongoClient
 
-from . import get_valid_kwargs
+from .._utils import get_valid_kwargs
 from .base import BaseCache, BaseStorage
 from .mongodb import MongoDict
 
diff --git a/requests_cache/backends/mongodb.py b/requests_cache/backends/mongodb.py
index 07a91ab..ef1fb51 100644
--- a/requests_cache/backends/mongodb.py
+++ b/requests_cache/backends/mongodb.py
@@ -28,7 +28,8 @@ from typing import Iterable
 
 from pymongo import MongoClient
 
-from . import BaseCache, BaseStorage, get_valid_kwargs
+from .._utils import get_valid_kwargs
+from . import BaseCache, BaseStorage
 
 
 class MongoCache(BaseCache):
diff --git a/requests_cache/backends/redis.py b/requests_cache/backends/redis.py
index 028968a..41d908a 100644
--- a/requests_cache/backends/redis.py
+++ b/requests_cache/backends/redis.py
@@ -35,8 +35,9 @@ from typing import Iterable
 
 from redis import Redis, StrictRedis
 
+from .._utils import get_valid_kwargs
 from ..cache_keys import decode, encode
-from . import BaseCache, BaseStorage, get_valid_kwargs
+from . import BaseCache, BaseStorage
 
 
 class RedisCache(BaseCache):
diff --git a/requests_cache/backends/sqlite.py b/requests_cache/backends/sqlite.py
index aa7f4d4..7262fdc 100644
--- a/requests_cache/backends/sqlite.py
+++ b/requests_cache/backends/sqlite.py
@@ -77,7 +77,8 @@ from typing import Collection, Iterable, Iterator, List, Tuple, Type, Union
 
 from appdirs import user_cache_dir
 
-from . import BaseCache, BaseStorage, get_valid_kwargs
+from .._utils import chunkify, get_valid_kwargs
+from . import BaseCache, BaseStorage
 
 MEMORY_URI = 'file::memory:?cache=shared'
 SQLITE_MAX_VARIABLE_NUMBER = 999
@@ -241,7 +242,7 @@ class SQLiteDict(BaseStorage):
         column = 'key' if keys else 'value'
         with self.connection(commit=True) as con:
             # Split into small enough chunks for SQLite to handle
-            for chunk in chunkify(keys or values):
+            for chunk in chunkify(keys or values, max_size=SQLITE_MAX_VARIABLE_NUMBER):
                 marks, args = _format_sequence(chunk)
                 statement = f'DELETE FROM {self.table_name} WHERE {column} IN ({marks})'
                 con.execute(statement, args)
@@ -270,13 +271,6 @@ class SQLitePickleDict(SQLiteDict):
         return self.serializer.loads(super().__getitem__(key))
 
 
-def chunkify(iterable: Iterable, max_size=SQLITE_MAX_VARIABLE_NUMBER) -> Iterator[List]:
-    """Split an iterable into chunks of a max size"""
-    iterable = list(iterable)
-    for index in range(0, len(iterable), max_size):
-        yield iterable[index : index + max_size]
-
-
 def _format_sequence(values: Collection) -> Tuple[str, List]:
     """Get SQL parameter marks for a sequence-based query, and ensure value is a sequence"""
     if not isinstance(values, Iterable):
diff --git a/requests_cache/cache_control.py b/requests_cache/cache_control.py
index 5b238d8..d7d6f2c 100644
--- a/requests_cache/cache_control.py
+++ b/requests_cache/cache_control.py
@@ -20,6 +20,8 @@ from typing import TYPE_CHECKING, Any, Dict, Mapping, Optional, Tuple, Union
 from attr import define, field
 from requests import PreparedRequest, Response
 
+from ._utils import coalesce
+
 if TYPE_CHECKING:
     from .models import CachedResponse
 
@@ -151,11 +153,6 @@ class CacheActions:
         self.skip_write = (expire_immediately or no_store) and not has_validator
 
 
-def coalesce(*values: Any, default=None) -> Any:
-    """Get the first non-``None`` value in a list of values"""
-    return next((v for v in values if v is not None), default)
-
-
 def get_expiration_datetime(expire_after: ExpirationTime) -> Optional[datetime]:
     """Convert an expiration value in any supported format to an absolute datetime"""
     # Never expire
diff --git a/requests_cache/cache_keys.py b/requests_cache/cache_keys.py
index 19b518a..d2a92cf 100644
--- a/requests_cache/cache_keys.py
+++ b/requests_cache/cache_keys.py
@@ -16,7 +16,7 @@ from requests import Request, Session
 from requests.models import CaseInsensitiveDict
 from url_normalize import url_normalize
 
-from . import get_valid_kwargs
+from ._utils import get_valid_kwargs
 
 if TYPE_CHECKING:
     from .models import AnyPreparedRequest, AnyRequest, CachedResponse
diff --git a/requests_cache/serializers/preconf.py b/requests_cache/serializers/preconf.py
index 5b79066..24b0546 100644
--- a/requests_cache/serializers/preconf.py
+++ b/requests_cache/serializers/preconf.py
@@ -19,7 +19,7 @@ from cattr.preconf import bson as bson_preconf
 from cattr.preconf import json as json_preconf
 from cattr.preconf import msgpack, orjson, pyyaml, tomlkit, ujson
 
-from .. import get_placeholder_class
+from .._utils import get_placeholder_class
 from .cattrs import CattrStage
 from .pipeline import SerializerPipeline, Stage
 
diff --git a/requests_cache/session.py b/requests_cache/session.py
index 22bfd50..3b26b4a 100644
--- a/requests_cache/session.py
+++ b/requests_cache/session.py
@@ -23,7 +23,7 @@ from requests import Session as OriginalSession
 from requests.hooks import dispatch_hook
 from urllib3 import filepost
 
-from . import get_valid_kwargs
+from ._utils import get_valid_kwargs
 from .backends import BackendSpecifier, init_backend
 from .cache_control import CacheActions, ExpirationTime, get_expiration_seconds
 from .models import AnyResponse, CachedResponse, set_response_defaults
diff --git a/tests/integration/test_mongodb.py b/tests/integration/test_mongodb.py
index ff8b467..77ab3ed 100644
--- a/tests/integration/test_mongodb.py
+++ b/tests/integration/test_mongodb.py
@@ -3,14 +3,8 @@ from unittest.mock import patch
 import pytest
 from pymongo import MongoClient
 
-from requests_cache.backends import (
-    GridFSCache,
-    GridFSPickleDict,
-    MongoCache,
-    MongoDict,
-    MongoPickleDict,
-    get_valid_kwargs,
-)
+from requests_cache._utils import get_valid_kwargs
+from requests_cache.backends import GridFSCache, GridFSPickleDict, MongoCache, MongoDict, MongoPickleDict
 from tests.conftest import fail_if_no_connection
 from tests.integration.base_cache_test import BaseCacheTest
 from tests.integration.base_storage_test import BaseStorageTest
diff --git a/tests/unit/test_session.py b/tests/unit/test_session.py
index 45bec2c..d3509de 100644
--- a/tests/unit/test_session.py
+++ b/tests/unit/test_session.py
@@ -14,13 +14,8 @@ from requests import Request
 from requests.structures import CaseInsensitiveDict
 
 from requests_cache import ALL_METHODS, CachedResponse, CachedSession
-from requests_cache.backends import (
-    BACKEND_CLASSES,
-    BaseCache,
-    SQLiteDict,
-    SQLitePickleDict,
-    get_placeholder_class,
-)
+from requests_cache._utils import get_placeholder_class
+from requests_cache.backends import BACKEND_CLASSES, BaseCache, SQLiteDict, SQLitePickleDict
 from requests_cache.backends.base import DESERIALIZE_ERRORS
 from requests_cache.cache_keys import create_key
 from tests.conftest import (