refactor: cleaning of using package/global defaults (#193)

* refactor: cleaning of using package/global defaults

* Literal

* MissingMongetter

* typos

* cleaning

* types

* note

* isort

* move loweer

* resolve

* global

* nonlocal

* import

* fall

* core = _MongoCore(None, _test_mongetter, 0)

Author: Borda

.pre-commit-config.yaml

@@ -66,10 +66,10 @@ repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
     rev: v0.2.1
     hooks:
+      # use black formatting
+      - id: ruff-format
+        name: Black by Ruff
       # basic check
       - id: ruff
         name: Ruff check
         args: ["--fix"]
-      # use black formatting
-      - id: ruff-format
-        name: Black by Ruff

cachier/__init__.py

@@ -1,11 +1,11 @@
 from ._version import *  # noqa: F403
-from .core import (
-    cachier,
+from .config import (
     disable_caching,
     enable_caching,
     get_default_params,
     set_default_params,
 )
+from .core import cachier
 
 __all__ = [
     "cachier",

cachier/_types.py

@@ -0,0 +1,9 @@
+from typing import TYPE_CHECKING, Callable, Literal
+
+if TYPE_CHECKING:
+    import pymongo.collection
+
+
+HashFunc = Callable[..., str]
+Mongetter = Callable[[], "pymongo.collection.Collection"]
+Backend = Literal["pickle", "mongo", "memory"]

cachier/config.py

@@ -0,0 +1,95 @@
+import datetime
+import hashlib
+import os
+import pickle
+from typing import Optional, TypedDict, Union
+
+from ._types import Backend, HashFunc, Mongetter
+
+
+def _default_hash_func(args, kwds):
+    # Sort the kwargs to ensure consistent ordering
+    sorted_kwargs = sorted(kwds.items())
+    # Serialize args and sorted_kwargs using pickle or similar
+    serialized = pickle.dumps((args, sorted_kwargs))
+    # Create a hash of the serialized data
+    return hashlib.sha256(serialized).hexdigest()
+
+
+class Params(TypedDict):
+    caching_enabled: bool
+    hash_func: HashFunc
+    backend: Backend
+    mongetter: Optional[Mongetter]
+    stale_after: datetime.timedelta
+    next_time: bool
+    cache_dir: Union[str, os.PathLike]
+    pickle_reload: bool
+    separate_files: bool
+    wait_for_calc_timeout: int
+    allow_none: bool
+
+
+_default_params: Params = {
+    "caching_enabled": True,
+    "hash_func": _default_hash_func,
+    "backend": "pickle",
+    "mongetter": None,
+    "stale_after": datetime.timedelta.max,
+    "next_time": False,
+    "cache_dir": "~/.cachier/",
+    "pickle_reload": True,
+    "separate_files": False,
+    "wait_for_calc_timeout": 0,
+    "allow_none": False,
+}
+
+
+def _update_with_defaults(param, name: str):
+    import cachier
+
+    if param is None:
+        return cachier.config._default_params[name]
+    return param
+
+
+def set_default_params(**params):
+    """Configure global parameters applicable to all memoized functions.
+
+    This function takes the same keyword parameters as the ones defined in the
+    decorator, which can be passed all at once or with multiple calls.
+    Parameters given directly to a decorator take precedence over any values
+    set by this function.
+
+    Only 'stale_after', 'next_time', and 'wait_for_calc_timeout' can be changed
+    after the memoization decorator has been applied. Other parameters will
+    only have an effect on decorators applied after this function is run.
+
+    """
+    import cachier
+
+    valid_params = (
+        p for p in params.items() if p[0] in cachier.config._default_params
+    )
+    _default_params.update(valid_params)
+
+
+def get_default_params():
+    """Get current set of default parameters."""
+    import cachier
+
+    return cachier.config._default_params
+
+
+def enable_caching():
+    """Enable caching globally."""
+    import cachier
+
+    cachier.config._default_params["caching_enabled"] = True
+
+
+def disable_caching():
+    """Disable caching globally."""
+    import cachier
+
+    cachier.config._default_params["caching_enabled"] = False

cachier/core.py

@@ -7,28 +7,27 @@
 # http://www.opensource.org/licenses/MIT-license
 # Copyright (c) 2016, Shay Palachy <shaypal5@gmail.com>
 
-# python 2 compatibility
-
 import datetime
-import hashlib
 import inspect
 import os
-import pickle
 from collections import OrderedDict
 from concurrent.futures import ThreadPoolExecutor
 from functools import wraps
-from typing import TYPE_CHECKING, Callable, Literal, Optional, TypedDict, Union
+from typing import Optional, Union
 from warnings import warn
 
+from .config import (
+    Backend,
+    HashFunc,
+    Mongetter,
+    _default_params,
+    _update_with_defaults,
+)
 from .cores.base import RecalculationNeeded, _BaseCore
 from .cores.memory import _MemoryCore
 from .cores.mongo import _MongoCore
 from .cores.pickle import _PickleCore
 
-if TYPE_CHECKING:
-    import pymongo.collection
-
-
 MAX_WORKERS_ENVAR_NAME = "CACHIER_MAX_WORKERS"
 DEFAULT_MAX_WORKERS = 8
 
@@ -68,15 +67,6 @@ def _calc_entry(core, key, func, args, kwds):
         core.mark_entry_not_calculated(key)
 
 
-def _default_hash_func(args, kwds):
-    # Sort the kwargs to ensure consistent ordering
-    sorted_kwargs = sorted(kwds.items())
-    # Serialize args and sorted_kwargs using pickle or similar
-    serialized = pickle.dumps((args, sorted_kwargs))
-    # Create a hash of the serialized data
-    return hashlib.sha256(serialized).hexdigest()
-
-
 def _convert_args_kwargs(
     func, _is_method: bool, args: tuple, kwds: dict
 ) -> dict:
@@ -103,44 +93,6 @@ def _convert_args_kwargs(
     return OrderedDict(sorted(kwargs.items()))
 
 
-class MissingMongetter(ValueError):
-    """Thrown when the mongetter keyword argument is missing."""
-
-
-HashFunc = Callable[..., str]
-Mongetter = Callable[[], "pymongo.collection.Collection"]
-Backend = Literal["pickle", "mongo", "memory"]
-
-
-class Params(TypedDict):
-    caching_enabled: bool
-    hash_func: HashFunc
-    backend: Backend
-    mongetter: Optional[Mongetter]
-    stale_after: datetime.timedelta
-    next_time: bool
-    cache_dir: Union[str, os.PathLike]
-    pickle_reload: bool
-    separate_files: bool
-    wait_for_calc_timeout: int
-    allow_none: bool
-
-
-_default_params: Params = {
-    "caching_enabled": True,
-    "hash_func": _default_hash_func,
-    "backend": "pickle",
-    "mongetter": None,
-    "stale_after": datetime.timedelta.max,
-    "next_time": False,
-    "cache_dir": "~/.cachier/",
-    "pickle_reload": True,
-    "separate_files": False,
-    "wait_for_calc_timeout": 0,
-    "allow_none": False,
-}
-
-
 def cachier(
     hash_func: Optional[HashFunc] = None,
     hash_params: Optional[HashFunc] = None,
@@ -219,13 +171,12 @@ def cachier(
         )
         warn(message, DeprecationWarning, stacklevel=2)
         hash_func = hash_params
+    # Update parameters with defaults if input is None
+    backend = _update_with_defaults(backend, "backend")
+    mongetter = _update_with_defaults(mongetter, "mongetter")
     # Override the backend parameter if a mongetter is provided.
-    if mongetter is None:
-        mongetter = _default_params["mongetter"]
     if callable(mongetter):
         backend = "mongo"
-    if backend is None:
-        backend = _default_params["backend"]
     core: _BaseCore
     if backend == "pickle":
         core = _PickleCore(
@@ -234,23 +185,16 @@ def cachier(
             cache_dir=cache_dir,
             separate_files=separate_files,
             wait_for_calc_timeout=wait_for_calc_timeout,
-            default_params=_default_params,
         )
     elif backend == "mongo":
-        if mongetter is None:
-            raise MissingMongetter(
-                "must specify ``mongetter`` when using the mongo core"
-            )
         core = _MongoCore(
-            mongetter=mongetter,
             hash_func=hash_func,
+            mongetter=mongetter,
             wait_for_calc_timeout=wait_for_calc_timeout,
-            default_params=_default_params,
         )
     elif backend == "memory":
         core = _MemoryCore(
-            hash_func=hash_func,
-            default_params=_default_params,
+            hash_func=hash_func, wait_for_calc_timeout=wait_for_calc_timeout
         )
     else:
         raise ValueError("specified an invalid core: %s" % backend)
@@ -261,11 +205,7 @@ def _cachier_decorator(func):
         @wraps(func)
         def func_wrapper(*args, **kwds):
             nonlocal allow_none
-            _allow_none = (
-                allow_none
-                if allow_none is not None
-                else _default_params["allow_none"]
-            )
+            _allow_none = _update_with_defaults(allow_none, "allow_none")
             # print('Inside general wrapper for {}.'.format(func.__name__))
             ignore_cache = kwds.pop("ignore_cache", False)
             overwrite_cache = kwds.pop("overwrite_cache", False)
@@ -289,10 +229,10 @@ def func_wrapper(*args, **kwds):
             _print("Entry found.")
             if _allow_none or entry.get("value", None) is not None:
                 _print("Cached result found.")
-                local_stale_after = (
-                    stale_after or _default_params["stale_after"]
+                local_stale_after = _update_with_defaults(
+                    stale_after, "stale_after"
                 )
-                local_next_time = next_time or _default_params["next_time"]  # noqa: E501
+                local_next_time = _update_with_defaults(next_time, "next_time")
                 now = datetime.datetime.now()
                 if now - entry["time"] <= local_stale_after:
                     _print("And it is fresh!")
@@ -362,35 +302,3 @@ def precache_value(*args, value_to_cache, **kwds):
         return func_wrapper
 
     return _cachier_decorator
-
-
-def set_default_params(**params):
-    """Configure global parameters applicable to all memoized functions.
-
-    This function takes the same keyword parameters as the ones defined in the
-    decorator, which can be passed all at once or with multiple calls.
-    Parameters given directly to a decorator take precedence over any values
-    set by this function.
-
-    Only 'stale_after', 'next_time', and 'wait_for_calc_timeout' can be changed
-    after the memoization decorator has been applied. Other parameters will
-    only have an effect on decorators applied after this function is run.
-
-    """
-    valid_params = (p for p in params.items() if p[0] in _default_params)
-    _default_params.update(valid_params)
-
-
-def get_default_params():
-    """Get current set of default parameters."""
-    return _default_params
-
-
-def enable_caching():
-    """Enable caching globally."""
-    _default_params["caching_enabled"] = True
-
-
-def disable_caching():
-    """Disable caching globally."""
-    _default_params["caching_enabled"] = False

cachier/cores/base.py

@@ -8,6 +8,10 @@
 
 import abc  # for the _BaseCore abstract base class
 import inspect
+import threading
+
+from .._types import HashFunc
+from ..config import _update_with_defaults
 
 
 class RecalculationNeeded(Exception):
@@ -17,9 +21,10 @@ class RecalculationNeeded(Exception):
 class _BaseCore:
     __metaclass__ = abc.ABCMeta
 
-    def __init__(self, hash_func, default_params):
-        self.default_params = default_params
-        self.hash_func = hash_func
+    def __init__(self, hash_func: HashFunc, wait_for_calc_timeout: int):
+        self.hash_func = _update_with_defaults(hash_func, "hash_func")
+        self.wait_for_calc_timeout = wait_for_calc_timeout
+        self.lock = threading.RLock()
 
     def set_func(self, func):
         """Sets the function this core will use.
@@ -37,10 +42,7 @@ def set_func(self, func):
 
     def get_key(self, args, kwds):
         """Returns a unique key based on the arguments provided."""
-        if self.hash_func is not None:
-            return self.hash_func(args, kwds)
-        else:
-            return self.default_params["hash_func"](args, kwds)
+        return self.hash_func(args, kwds)
 
     def get_entry(self, args, kwds):
         """Returns the result mapped to the given arguments in this core's
@@ -56,10 +58,9 @@ def precache_value(self, args, kwds, value_to_cache):
 
     def check_calc_timeout(self, time_spent):
         """Raise an exception if a recalculation is needed."""
-        if self.wait_for_calc_timeout is not None:
-            calc_timeout = self.wait_for_calc_timeout
-        else:
-            calc_timeout = self.default_params["wait_for_calc_timeout"]
+        calc_timeout = _update_with_defaults(
+            self.wait_for_calc_timeout, "wait_for_calc_timeout"
+        )
         if calc_timeout > 0 and (time_spent >= calc_timeout):
             raise RecalculationNeeded()