Index and Webclient View caching

CHANGELOG

@@ -85,6 +85,8 @@ Core:
 - Added custom translations in config [#3383].
 - Added dynamic webpage title [#3404].
 - Added 'go to top'-link [#3404].
+- Added caching for the index views. When using a Webserver for serving
+  static files see the example configuration in the PR [#3419].
 
 Mediafiles:
 - Fixed reloading of PDF on page change [#3274].

openslides/core/views.py

@@ -3,11 +3,10 @@ import uuid
 from collections import OrderedDict
 from operator import attrgetter
 from textwrap import dedent
-from typing import Any, Dict, List  # noqa
+from typing import Any, Dict, List, cast  # noqa
 
 from django.apps import apps
 from django.conf import settings
-from django.contrib.staticfiles import finders
 from django.db.models import F
 from django.http import Http404, HttpResponse
 from django.utils.timezone import now
@@ -54,7 +53,7 @@ from .models import (
 
 # Special Django views
 
-class IndexView(utils_views.CSRFMixin, utils_views.View):
+class IndexView(utils_views.CSRFMixin, utils_views.IndexView):
     """
     The primary view for OpenSlides using AngularJS.
 
@@ -62,28 +61,20 @@ class IndexView(utils_views.CSRFMixin, utils_views.View):
     You can override it by simply adding a custom 'templates/index.html' file
     to the custom staticfiles directory. See STATICFILES_DIRS in settings.py.
     """
-
+    template_name = 'templates/index.html'
-    def get(self, *args, **kwargs):
-        with open(finders.find('templates/index.html')) as f:
-            content = f.read()
-        return HttpResponse(content)
 
 
-class ProjectorView(utils_views.View):
+class ProjectorView(utils_views.IndexView):
     """
     The primary view for OpenSlides projector using AngularJS.
 
     The projector container template is 'openslides/core/static/templates/projector-container.html'.
     This container is for controlling the projector resolution.
     """
-
+    template_name = 'templates/projector-container.html'
-    def get(self, *args, **kwargs):
-        with open(finders.find('templates/projector-container.html')) as f:
-            content = f.read()
-        return HttpResponse(content)
 
 
-class RealProjectorView(utils_views.View):
+class RealProjectorView(utils_views.IndexView):
     """
     The original view without resolutioncontrol for OpenSlides projector using AngularJS.
 
@@ -92,11 +83,7 @@ class RealProjectorView(utils_views.View):
     file to the custom staticfiles directory. See STATICFILES_DIRS in
     settings.py.
     """
-
+    template_name = 'templates/projector.html'
-    def get(self, *args, **kwargs):
-        with open(finders.find('templates/projector.html')) as f:
-            content = f.read()
-        return HttpResponse(content)
 
 
 class WebclientJavaScriptView(utils_views.View):
@@ -105,10 +92,15 @@ class WebclientJavaScriptView(utils_views.View):
     AngularJS app for the requested realm (site or projector). Also code
     for plugins is appended. The result is not uglified.
     """
-    def get(self, *args, **kwargs):
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
-        angular_modules = []
+        super().__init__(*args, **kwargs)
+        self.cache = {}  # type: Dict[str, str]
+        self.init_cache('site')
+        self.init_cache('projector')
+
+    def init_cache(self, realm: str) -> None:
+        angular_modules = []  # type: List[str]
         js_files = []  # type: List[str]
-        realm = kwargs.get('realm')  # Result is 'site' or 'projector'
         for app_config in apps.get_app_configs():
             # Add the angular app if the module has one.
             if getattr(app_config, 'angular_{}_module'.format(realm), False):
@@ -187,8 +179,11 @@ class WebclientJavaScriptView(utils_views.View):
             """
             }());
             """)
+        self.cache[realm] = content
 
-        return HttpResponse(content, content_type='application/javascript')
+    def get(self, *args: Any, **kwargs: Any) -> HttpResponse:
+        realm = cast(str, kwargs.get('realm'))  # Result is 'site' or 'projector'
+        return HttpResponse(self.cache[realm], content_type='application/javascript')
 
 
 # Viewsets for the REST API

openslides/utils/views.py

@@ -1,5 +1,8 @@
 from typing import Any, Dict, List  # noqa
 
+from django.contrib.staticfiles import finders
+from django.core.exceptions import ImproperlyConfigured
+from django.http import HttpResponse
 from django.views.decorators.csrf import ensure_csrf_cookie
 from django.views.generic.base import View
 from rest_framework.response import Response
@@ -45,3 +48,22 @@ class APIView(_APIView):
     # Add the http-methods and delete the method "method_call"
     get = post = put = patch = delete = head = options = trace = method_call
     del method_call
+
+
+class IndexView(View):
+    """
+    A view to serve a single cached template file. Subclasses has to provide 'template_name'.
+    """
+    template_name = None  # type: str
+
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
+        super().__init__(*args, **kwargs)
+
+        if self.template_name is None:
+            raise ImproperlyConfigured("'template_name' is not provided")
+
+        with open(finders.find(self.template_name)) as template:
+            self.template = template.read()
+
+    def get(self, *args: Any, **kwargs: Any) -> HttpResponse:
+        return HttpResponse(self.template)

tests/unit/core/test_views.py

@@ -169,10 +169,11 @@ class ProjectorAPI(TestCase):
 class WebclientJavaScriptView(TestCase):
     def setUp(self):
         self.request = MagicMock()
-        self.view_instance = views.WebclientJavaScriptView()
-        self.view_instance.request = self.request
 
     @patch('django.contrib.auth.models.Permission.objects.all')
     def test_permissions_as_constant(self, mock_all):
-        self.view_instance.get()
+        self.view_instance = views.WebclientJavaScriptView()
-        self.assertEqual(mock_all.call_count, 1)
+        self.view_instance.request = self.request
+        response = self.view_instance.get(realm='site')
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(mock_all.call_count, 2)