Add request-level caching for registry lookups

Cache value lookups, __contains__, and forInterface proxies per request.
Add get_registry() convenience function caching getUtility(IRegistry).

Author: jensens

setup.py

@@ -40,6 +40,7 @@
     python_requires=">=3.10",
     install_requires=[
         "Zope",
+        "zope.globalrequest",
     ],
     extras_require={"test": ["plone.schema"]},
     entry_points="""

src/plone/registry/__init__.py

@@ -1,3 +1,4 @@
 from plone.registry.fieldref import FieldRef
 from plone.registry.record import Record
+from plone.registry.registry import get_registry
 from plone.registry.registry import Registry

src/plone/registry/registry.py

@@ -11,15 +11,47 @@
 from plone.registry.record import Record
 from plone.registry.recordsproxy import RecordsProxy
 from plone.registry.recordsproxy import RecordsProxyCollection
+from zope.component import getUtility
 from zope.component import queryAdapter
 from zope.event import notify
+from zope.globalrequest import getRequest
 from zope.interface import implementer
 from zope.schema import getFieldNames
 from zope.schema import getFieldsInOrder
 
 import re
 import warnings
 
+_CACHE_MARKER = object()
+
+
+def _get_request_cache():
+    """Return the per-request value cache dict, or None if no request."""
+    request = getRequest()
+    if request is None:
+        return None
+    cache = getattr(request, "_plone_registry_cache", None)
+    if cache is None:
+        cache = {}
+        request._plone_registry_cache = cache
+    return cache
+
+
+def get_registry():
+    """Get the registry utility, cached per-request.
+
+    Falls back to getUtility(IRegistry) when no request is active.
+    """
+    request = getRequest()
+    if request is not None:
+        registry = getattr(request, "_plone_registry", None)
+        if registry is not None:
+            return registry
+    registry = getUtility(IRegistry)
+    if request is not None:
+        request._plone_registry = registry
+    return registry
+
 
 @implementer(IRegistry)
 class Registry(Persistent):
@@ -31,20 +63,40 @@ def __init__(self):
     # Basic value access API
 
     def __getitem__(self, name):
-        # Fetch straight from records._values to avoid loading the field
-        # as a separate persistent object
-        return self.records._values[name]
+        cache = _get_request_cache()
+        if cache is not None:
+            value = cache.get(name, _CACHE_MARKER)
+            if value is not _CACHE_MARKER:
+                return value
+        value = self.records._values[name]
+        if cache is not None:
+            cache[name] = value
+        return value
 
     def get(self, name, default=None):
-        # Fetch straight from records._values to avoid loading the field
-        # as a separate persistent object
-        return self.records._values.get(name, default)
+        cache = _get_request_cache()
+        if cache is not None:
+            value = cache.get(name, _CACHE_MARKER)
+            if value is not _CACHE_MARKER:
+                return value
+        value = self.records._values.get(name, _CACHE_MARKER)
+        if value is _CACHE_MARKER:
+            return default
+        if cache is not None:
+            cache[name] = value
+        return value
 
     def __setitem__(self, name, value):
         # make sure we get the Record class' validation
         self.records[name].value = value
+        cache = _get_request_cache()
+        if cache is not None:
+            cache[name] = value
 
     def __contains__(self, name):
+        cache = _get_request_cache()
+        if cache is not None and name in cache:
+            return True
         return name in self.records._values
 
     # Records - make this a property so that it's readonly
@@ -65,6 +117,14 @@ def forInterface(self, interface, check=True, omit=(), prefix=None, factory=None
         if not prefix.endswith("."):
             prefix += "."
 
+        # Try per-request proxy cache
+        cache = _get_request_cache()
+        cache_key = ("__proxy__", interface.__identifier__, prefix, omit)
+        if cache is not None:
+            proxy = cache.get(cache_key)
+            if proxy is not None:
+                return proxy
+
         if check:
             for name in getFieldNames(interface):
                 if name not in omit and prefix + name not in self:
@@ -76,7 +136,12 @@ def forInterface(self, interface, check=True, omit=(), prefix=None, factory=None
         if factory is None:
             factory = RecordsProxy
 
-        return factory(self, interface, omitted=omit, prefix=prefix)
+        proxy = factory(self, interface, omitted=omit, prefix=prefix)
+
+        if cache is not None:
+            cache[cache_key] = proxy
+
+        return proxy
 
     def registerInterface(self, interface, omit=(), prefix=None):
         if prefix is None: