Add support for header values as bytes

Fixes #705 (for 0.9)

HISTORY.md

@@ -5,6 +5,7 @@ Backport fixes from 1.0:
 * Fix potential `AttributeError` due to undetected imports when requests-cache is bundled in a PyInstaller package
 * Fix `AttributeError` when attempting to unpickle a `CachedSession` object, and instead disable
   pickling by raising a `NotImplementedError`
+* Add support for header values as bytes for compatibility with OAuth1 features of `requests-oauthlib`
 * Update to cattrs 22.2
 
 ## 0.9.6 (2022-08-24)

requests_cache/cache_control.py

@@ -187,7 +187,12 @@ def get_cache_directives(headers: Mapping) -> Dict:
 
     kv_directives = {}
     if headers.get('Cache-Control'):
-        cache_directives = headers['Cache-Control'].split(',')
+        cache_control = (
+            headers['Cache-Control'].decode()
+            if isinstance(headers['Cache-Control'], bytes)
+            else headers['Cache-Control']
+        )
+        cache_directives = cache_control.split(',')
         kv_directives = dict([split_kv_directive(value) for value in cache_directives])
 
     if 'Expires' in headers:

tests/unit/test_cache_control.py

@@ -65,6 +65,7 @@ def test_init(
         ({'Expires': HTTPDATE_STR}, None),  # Only valid for response headers
         ({'Cache-Control': 'max-age=60'}, 60),
         ({'Cache-Control': 'public, max-age=60'}, 60),
+        ({'Cache-Control': b'public, max-age=60'}, 60),
         ({'Cache-Control': 'max-age=0'}, DO_NOT_CACHE),
         ({'Cache-Control': 'no-store'}, DO_NOT_CACHE),
     ],