# HG changeset patch
# User Marcin Kuzminski <marcin@rhodecode.com>
# Date 2018-07-14 16:17:02
# Node ID 63610fd137c3a58dc42a0a0d4abb0610fef19c82
# Parent  30b993642c1d675cded8b91c1057fdd8ac784e25

caches: introduce new conditional cache function.

diff --git a/rhodecode/lib/rc_cache/__init__.py b/rhodecode/lib/rc_cache/__init__.py
--- a/rhodecode/lib/rc_cache/__init__.py
+++ b/rhodecode/lib/rc_cache/__init__.py
@@ -20,7 +20,6 @@
 
 import logging
 from dogpile.cache import register_backend
-from dogpile.cache import make_region
 
 register_backend(
     "dogpile.cache.rc.memory_lru", "rhodecode.lib.rc_cache.backends",
@@ -40,7 +39,7 @@ log = logging.getLogger(__name__)
 from . import region_meta
 from .utils import (
     get_default_cache_settings, key_generator, get_or_create_region,
-    clear_cache_namespace)
+    clear_cache_namespace, make_region)
 
 
 def configure_dogpile_cache(settings):
diff --git a/rhodecode/lib/rc_cache/utils.py b/rhodecode/lib/rc_cache/utils.py
--- a/rhodecode/lib/rc_cache/utils.py
+++ b/rhodecode/lib/rc_cache/utils.py
@@ -19,7 +19,10 @@
 # and proprietary license terms, please see https://rhodecode.com/licenses/
 import os
 import logging
-from dogpile.cache import make_region
+import functools
+
+from dogpile.cache import CacheRegion
+from dogpile.cache.util import compat
 
 from rhodecode.lib.utils import safe_str, sha1
 from . import region_meta
@@ -27,6 +30,82 @@ from . import region_meta
 log = logging.getLogger(__name__)
 
 
+class RhodeCodeCacheRegion(CacheRegion):
+
+    def conditional_cache_on_arguments(
+            self, namespace=None,
+            expiration_time=None,
+            should_cache_fn=None,
+            to_str=compat.string_type,
+            function_key_generator=None,
+            condition=True):
+        """
+        Custom conditional decorator, that will not touch any dogpile internals if
+        condition isn't meet. This works a bit different than should_cache_fn
+        And it's faster in cases we don't ever want to compute cached values
+        """
+        expiration_time_is_callable = compat.callable(expiration_time)
+
+        if function_key_generator is None:
+            function_key_generator = self.function_key_generator
+
+        def decorator(fn):
+            if to_str is compat.string_type:
+                # backwards compatible
+                key_generator = function_key_generator(namespace, fn)
+            else:
+                key_generator = function_key_generator(namespace, fn, to_str=to_str)
+
+            @functools.wraps(fn)
+            def decorate(*arg, **kw):
+                key = key_generator(*arg, **kw)
+
+                @functools.wraps(fn)
+                def creator():
+                    return fn(*arg, **kw)
+
+                if not condition:
+                    return creator()
+
+                timeout = expiration_time() if expiration_time_is_callable \
+                    else expiration_time
+
+                return self.get_or_create(key, creator, timeout, should_cache_fn)
+
+            def invalidate(*arg, **kw):
+                key = key_generator(*arg, **kw)
+                self.delete(key)
+
+            def set_(value, *arg, **kw):
+                key = key_generator(*arg, **kw)
+                self.set(key, value)
+
+            def get(*arg, **kw):
+                key = key_generator(*arg, **kw)
+                return self.get(key)
+
+            def refresh(*arg, **kw):
+                key = key_generator(*arg, **kw)
+                value = fn(*arg, **kw)
+                self.set(key, value)
+                return value
+
+            decorate.set = set_
+            decorate.invalidate = invalidate
+            decorate.refresh = refresh
+            decorate.get = get
+            decorate.original = fn
+            decorate.key_generator = key_generator
+
+            return decorate
+
+        return decorator
+
+
+def make_region(*arg, **kw):
+    return RhodeCodeCacheRegion(*arg, **kw)
+
+
 def get_default_cache_settings(settings, prefixes=None):
     prefixes = prefixes or []
     cache_settings = {}
diff --git a/rhodecode/lib/utils.py b/rhodecode/lib/utils.py
--- a/rhodecode/lib/utils.py
+++ b/rhodecode/lib/utils.py
@@ -120,7 +120,6 @@ def get_repo_group_slug(request):
         # pyramid
         _group = request.matchdict.get('repo_group_name')
 
-
     if _group:
         _group = _group.rstrip('/')
     return _group