Refactor session-level settings into separate CacheSettings class

2 files changed, 57 insertions, 0 deletions

diff --git a/requests_cache/models/__init__.py b/requests_cache/models/__init__.py
index 6ffc7ad..497ca3f 100644
--- a/requests_cache/models/__init__.py
+++ b/requests_cache/models/__init__.py
@@ -7,6 +7,7 @@ from requests import PreparedRequest, Request, Response
 from .raw_response import CachedHTTPResponse
 from .request import CachedRequest
 from .response import CachedResponse, set_response_defaults
+from .settings import CacheSettings
 
 AnyResponse = Union[Response, CachedResponse]
 AnyRequest = Union[Request, PreparedRequest, CachedRequest]
diff --git a/requests_cache/models/settings.py b/requests_cache/models/settings.py
new file mode 100644
index 0000000..01ad937
--- /dev/null
+++ b/requests_cache/models/settings.py
@@ -0,0 +1,56 @@
+from typing import TYPE_CHECKING, Callable, Dict, Iterable, Union
+
+from attr import define, field
+
+from .._utils import get_valid_kwargs
+from ..cache_control import ExpirationTime
+
+if TYPE_CHECKING:
+    from . import AnyResponse
+
+# Signatures for user-provided callbacks
+FilterCallback = Callable[['AnyResponse'], bool]
+KeyCallback = Callable[..., str]
+
+
+@define(init=False)
+class CacheSettings:
+    """Class to store cache settings used by :py:class:`.CachedSession` and backends.
+
+    Args:
+        allowable_codes: Only cache responses with one of these status codes
+        allowable_methods: Cache only responses for one of these HTTP methods
+        cache_control: Use Cache-Control headers to set expiration
+        expire_after: Time after which cached items will expire
+        filter_fn: Response filtering function that indicates whether or not a given response should
+            be cached.
+        ignored_parameters: List of request parameters to not match against, and exclude from the cache
+        key_fn: Request matching function for generating custom cache keys
+        match_headers: Match request headers when reading from the cache; may be either ``True`` or
+            a list of specific headers to match
+        stale_if_error: Return stale cache data if a new request raises an exception
+        urls_expire_after: Expiration times to apply for different URL patterns
+    """
+
+    allowable_codes: Iterable[int] = field(default=(200,))
+    allowable_methods: Iterable[str] = field(default=('GET', 'HEAD'))
+    cache_control: bool = field(default=False)
+    # cache_disabled: bool = field(default=False)
+    expire_after: ExpirationTime = field(default=-1)
+    filter_fn: FilterCallback = field(default=None)
+    ignored_parameters: Iterable[str] = field(default=None)
+    key_fn: KeyCallback = field(default=None)
+    match_headers: Union[Iterable[str], bool] = field(default=False)
+    stale_if_error: bool = field(default=False)
+    urls_expire_after: Dict[str, ExpirationTime] = field(factory=dict)
+
+    def __init__(self, **kwargs):
+        # Backwards-compatibility for old argument names
+        if 'old_data_on_error' in kwargs:
+            kwargs['stale_if_error'] = kwargs.pop('old_data_on_error')
+        if 'include_get_headers' in kwargs:
+            kwargs['match_headers'] = kwargs.pop('include_get_headers')
+
+        # Ignore invalid kwargs for easier initialization from mixed **kwargs
+        kwargs = get_valid_kwargs(self.__attrs_init__, kwargs)
+        self.__attrs_init__(**kwargs)