misc: cache get_page_choices result during a request (#19015)

combo/data/forms.py

@@ -21,6 +21,9 @@ from django import forms
 from .models import Page, ParametersCell, MenuCell, LinkCell, ConfigJsonCell
 from jsonfield.widgets import JSONWidget
 
+from combo.utils import cache_during_request
+
+
 class ParametersForm(forms.Form):
     choice = forms.ChoiceField(choices=[])
 
@@ -53,6 +56,7 @@ class ParametersCellForm(forms.ModelForm):
         }
 
 
+@cache_during_request
 def get_page_choices():
     pages = Page.get_as_reordered_flat_hierarchy(Page.objects.all())
     return [(x.id, '%s %s' % (u'\u00a0' * x.level * 2, x.title)) for x in pages]

combo/middleware.py

@@ -0,0 +1,36 @@
+# combo - content management system
+# Copyright (C) 2017  Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import threading
+
+
+_requests = {}
+
+def get_request():
+    return _requests.get(threading.current_thread())
+
+
+class GlobalRequestMiddleware(object):
+    def process_request(self, request):
+        _requests[threading.current_thread()] = request
+        request.cache = {}
+
+    def process_response(self, request, response):
+        del _requests[threading.current_thread()]
+        return response
+
+    def process_exception(self, request, exception):
+        return self.process_response(request, None)

combo/settings.py

@@ -89,6 +89,7 @@ INSTALLED_APPS = (
 INSTALLED_APPS = plugins.register_plugins_apps(INSTALLED_APPS)
 
 MIDDLEWARE_CLASSES = (
+    'combo.middleware.GlobalRequestMiddleware',
     'django.contrib.sessions.middleware.SessionMiddleware',
     'django.middleware.common.CommonMiddleware',
     'django.middleware.csrf.CsrfViewMiddleware',

combo/utils.py

@@ -39,6 +39,8 @@ from django.template import Context
 from django.utils.html import strip_tags
 from django.utils.http import urlencode, quote
 
+from .middleware import get_request
+
 
 class DecryptionError(Exception):
     pass
@@ -280,3 +282,42 @@ def check_string(s, signature, keys, algo='sha256'):
         if res == 0:
             return True
     return False
+
+# _make_key and _HashedSeq imported/adapted from functools from Python 3.2+
+def _make_key(args, kwds,
+             kwd_mark=(object(),),
+             fasttypes={int, str, frozenset, type(None)},
+             tuple=tuple, type=type, len=len):
+    key = args
+    if kwds:
+        key += kwd_mark
+        for item in kwds.items():
+            key += item
+    if len(key) == 1 and type(key[0]) in fasttypes:
+        return key[0]
+    return _HashedSeq(key)
+
+
+class _HashedSeq(list):
+    __slots__ = 'hashvalue'
+
+    def __init__(self, tup, hash=hash):
+        self[:] = tup
+        self.hashvalue = hash(tup)
+
+    def __hash__(self):
+        return self.hashvalue
+
+
+def cache_during_request(func):
+    def inner(*args, **kwargs):
+        request = get_request()
+        if request:
+            cache_key = (id(func), _make_key(args, kwargs))
+            if cache_key in request.cache:
+                return request.cache[cache_key]
+        result = func(*args, **kwargs)
+        if request:
+            request.cache[cache_key] = result
+        return result
+    return inner

tests/test_manager.py

@@ -3,6 +3,8 @@ import os
 import StringIO
 import urllib
 
+import mock
+
 from django.core.files.storage import default_storage
 from django.conf import settings
 from django.contrib.auth.models import User
@@ -585,3 +587,19 @@ def test_menu_json(app, admin_user):
     resp = app.get('/manage/menu.json?callback=fooBar')
     assert resp.headers['content-type'] == 'application/javascript'
     assert resp.content.startswith('fooBar([{"')
+
+def test_page_multiple_link_cells(app, admin_user):
+    Page.objects.all().delete()
+    page = Page(title='One', slug='one', template_name='standard')
+    page.save()
+    for i in range(10):
+        Page(title='page %d' % i, slug='page%d' % i, template_name='standard').save()
+        cell = LinkCell(page=page, placeholder='content', order=0)
+        cell.save()
+
+    patched_orig = Page.get_as_reordered_flat_hierarchy
+    app = login(app)
+    with mock.patch('combo.data.models.Page.get_as_reordered_flat_hierarchy') as func:
+        func.return_value = []
+        resp = app.get('/manage/pages/%s/' % page.id)
+        assert func.call_count == 1