expirable dict

ring/func_sync.py

@@ -4,6 +4,7 @@
 factories.
 """
 from typing import Any, Optional, List
+import functools
 import time
 import re
 import hashlib
@@ -174,7 +175,7 @@ def touch_many(self, keys, expire=Ellipsis):
         self.touch_many_values(keys, expire)
 
 
-class DictStorage(fbase.CommonMixinStorage, fbase.StorageMixin):
+class ExpirableDictStorage(fbase.CommonMixinStorage, fbase.StorageMixin):
 
     now = time.time
 
@@ -218,6 +219,28 @@ def touch_value(self, key, expire):
         self.backend[key] = expired_time, value
 
 
+class PersistentDictStorage(fbase.CommonMixinStorage, fbase.StorageMixin):
+
+    def get_value(self, key):
+        try:
+            value = self.backend[key]
+        except KeyError:
+            raise fbase.NotFound
+        return value
+
+    def set_value(self, key, value, expire):
+        self.backend[key] = value
+
+    def delete_value(self, key):
+        try:
+            del self.backend[key]
+        except KeyError:
+            pass
+
+    def has_value(self, key):
+        return key in self.backend
+
+
 class MemcacheStorage(
         fbase.CommonMixinStorage, fbase.StorageMixin, BulkStorageMixin):
 
@@ -282,6 +305,22 @@ def set_many_values(self, keys, values, expire):
 
 
 class DiskStorage(fbase.CommonMixinStorage, fbase.StorageMixin):
+
+    def get_value(self, key):
+        value = self.backend.get(key)
+        if value is None:
+            raise fbase.NotFound
+        return value
+
+    def set_value(self, key, value, expire):
+        self.backend.set(key, value, expire)
+
+    def delete_value(self, key):
+        self.backend.delete(key)
+
+
+class ShelveStorage(fbase.CommonMixinStorage, fbase.StorageMixin):
+
     def get_value(self, key):
         value = self.backend.get(key)
         if value is None:
@@ -298,7 +337,7 @@ def delete_value(self, key):
 def dict(
         obj, key_prefix=None, expire=None, coder=None, ignorable_keys=None,
         default_action='get_or_update', coder_registry=None,
-        user_interface=CacheUserInterface, storage_class=DictStorage):
+        user_interface=CacheUserInterface, storage_class=Ellipsis):
     """Basic Python :class:`dict` based cache.
 
     This backend is not designed for real products, but useful by
@@ -321,6 +360,12 @@ def dict(
 
     :see: :func:`ring.aiodict` for :mod:`asyncio` version.
     """
+    if storage_class is Ellipsis:
+        if expire is None:
+            storage_class = PersistentDictStorage
+        else:
+            storage_class = ExpirableDictStorage
+
     return fbase.factory(
         obj, key_prefix=key_prefix, on_manufactured=None,
         user_interface=user_interface, storage_class=storage_class,
@@ -329,6 +374,9 @@ def dict(
         ignorable_keys=ignorable_keys)
 
 
+shelve = functools.partial(dict, expire=None)
+
+
 def memcache(
         client, key_prefix=None, expire=0, coder=None, ignorable_keys=None,
         default_action='get_or_update', coder_registry=None,

tests/_test_interface.py

@@ -156,7 +156,7 @@ def f(a):
     assert f('10') == '10'
     raw_value = storage.get(f.key('10'))  # raw value
     value = f.decode(raw_value)
-    assert f.get('10') == value[1]
+    assert f.get('10') == value
 
 
 def test_coder_method():
@@ -190,4 +190,4 @@ def data(self):
 
     raw_value = storage.get(u1.data.key())
     value = u1.data.decode(raw_value)
-    assert u1.data.get() == value[1]
+    assert u1.data.get() == value

tests/test_action_trigger.py

@@ -39,7 +39,7 @@ def data(self):
     assert updated_data == data
 
     key = u1.data.run('key')
-    direct_data = cache[key][1]
+    direct_data = cache[key]
     assert data == direct_data
 
     with pytest.raises(TypeError):

tests/test_func_sync.py

@@ -238,7 +238,8 @@ def f():
 
     assert f.get() is None
     assert f() == 0
-    f.touch()
+    with pytest.raises(AttributeError):
+        f.touch()
 
 
 def test_func_dict_expire():

tests/test_workflow.py

@@ -38,7 +38,7 @@ def child(self, n):
 
     # do you want to access to cache directly?
     key = u1.data.key()
-    assert u1.data() == cache[key][1]  # whenever you want!
+    assert u1.data() == cache[key]  # whenever you want!
 
     u1._data['name'] = 'User renamed'
     assert u1.data() == {'user_id': 42, 'name': 'User 1'}  # still cached