Correct RENDER_PANELS functionality and when enabled disable HistoryPanel

debug_toolbar/panels/history/panel.py

@@ -21,6 +21,12 @@ class HistoryPanel(Panel):
     nav_title = _("History")
     template = "debug_toolbar/panels/history.html"
 
+    @property
+    def enabled(self):
+        # Do not show the history panel if the panels are rendered on request
+        # rather than loaded via ajax.
+        return super().enabled and not self.toolbar.should_render_panels()
+
     @property
     def is_historical(self):
         """The HistoryPanel should not be included in the historical panels."""

debug_toolbar/templates/debug_toolbar/base.html

@@ -7,7 +7,10 @@
 <script type="module" src="{% static 'debug_toolbar/js/toolbar.js' %}" async></script>
 {% endblock %}
 <div id="djDebug" class="djdt-hidden" dir="ltr"
-     {% if toolbar.store_id %}data-store-id="{{ toolbar.store_id }}" data-render-panel-url="{% url 'djdt:render_panel' %}"{% endif %}
+     {% if not toolbar.should_render_panels %}
+     data-store-id="{{ toolbar.store_id }}"
+     data-render-panel-url="{% url 'djdt:render_panel' %}"
+     {% endif %}
      data-default-show="{% if toolbar.config.SHOW_COLLAPSED %}false{% else %}true{% endif %}"
      {{ toolbar.config.ROOT_TAG_EXTRA_ATTRS|safe }}>
   <div class="djdt-hidden" id="djDebugToolbar">

debug_toolbar/templates/debug_toolbar/includes/panel_content.html

@@ -7,11 +7,11 @@
       <h3>{{ panel.title }}</h3>
     </div>
     <div class="djDebugPanelContent">
-      {% if toolbar.store_id %}
+      {% if toolbar.should_render_panels %}
+        <div class="djdt-scroll">{{ panel.content }}</div>
+      {% else %}
         <div class="djdt-loader"></div>
         <div class="djdt-scroll"></div>
-      {% else %}
-        <div class="djdt-scroll">{{ panel.content }}</div>
       {% endif %}
     </div>
   </div>

debug_toolbar/toolbar.py

@@ -79,6 +79,10 @@ def render_toolbar(self):
                 raise
 
     def should_render_panels(self):
+        """Determine whether the panels should be rendered during the request
+
+        If False, the panels will be loaded via Ajax.
+        """
         render_panels = self.config["RENDER_PANELS"]
         if render_panels is None:
             render_panels = self.request.META["wsgi.multiprocess"]

docs/changes.rst

@@ -5,6 +5,11 @@ Next version
 ------------
 
 * Ensured that the handle stays within bounds when resizing the window.
+* Disabled ``HistoryPanel`` when ``RENDER_PANELS`` is ``True``
+  or if ``RENDER_PANELS`` is ``None`` and the WSGI container is
+  running with multiple processes.
+* Fixed ``RENDER_PANELS`` functionality so that when ``True`` panels are
+  rendered during the request and not loaded asynchronously.
 
 
 3.2.1 (2021-04-14)

docs/configuration.rst

@@ -66,19 +66,24 @@ Toolbar options
   The toolbar searches for this string in the HTML and inserts itself just
   before.
 
+.. _RENDER_PANELS:
+
 * ``RENDER_PANELS``
 
   Default: ``None``
 
   If set to ``False``, the debug toolbar will keep the contents of panels in
-  memory on the server and load them on demand. If set to ``True``, it will
-  render panels inside every page. This may slow down page rendering but it's
+  memory on the server and load them on demand.
+
+  If set to ``True``, it will disable ``HistoryPanel`` and render panels
+  inside every page. This may slow down page rendering but it's
   required on multi-process servers, for example if you deploy the toolbar in
   production (which isn't recommended).
 
   The default value of ``None`` tells the toolbar to automatically do the
   right thing depending on whether the WSGI container runs multiple processes.
-  This setting allows you to force a different behavior if needed.
+  This setting allows you to force a different behavior if needed. If the
+  WSGI container runs multiple processes, it will disable ``HistoryPanel``.
 
 * ``RESULTS_CACHE_SIZE``
 

docs/installation.rst

@@ -147,3 +147,11 @@ And for Apache:
 .. _JavaScript module: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
 .. _CORS errors: https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS/Errors/CORSMissingAllowOrigin
 .. _Access-Control-Allow-Origin header: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Access-Control-Allow-Origin
+
+Django Channels & Async
+^^^^^^^^^^^^^^^^^^^^^^^
+
+The Debug Toolbar currently doesn't support Django Channels or async projects.
+If you are using Django channels are having issues getting panels to load,
+please review the documentation for the configuration option
+:ref:`RENDER_PANELS <RENDER_PANELS>`.

docs/panels.rst

@@ -17,6 +17,11 @@ History
 This panel shows the history of requests made and allows switching to a past
 snapshot of the toolbar to view that request's stats.
 
+.. caution::
+   If :ref:`RENDER_PANELS <RENDER_PANELS>` configuration option is set to
+   ``True`` or if the server runs with multiple processes, the History Panel
+   will be disabled.
+
 Version
 ~~~~~~~
 

docs/spelling_wordlist.txt

@@ -37,3 +37,4 @@ unhashable
 uWSGI
 validator
 Werkzeug
+async

tests/test_integration.py

@@ -321,11 +321,44 @@ def test_sql_profile_checks_show_toolbar(self):
             self.assertEqual(response.status_code, 404)
 
     @override_settings(DEBUG_TOOLBAR_CONFIG={"RENDER_PANELS": True})
-    def test_data_store_id_not_rendered_when_none(self):
+    def test_render_panels_in_request(self):
+        """
+        Test that panels are are rendered during the request with
+        RENDER_PANELS=TRUE
+        """
         url = "/regular/basic/"
         response = self.client.get(url)
         self.assertIn(b'id="djDebug"', response.content)
+        # Verify the store id is not included.
         self.assertNotIn(b"data-store-id", response.content)
+        # Verify the history panel was disabled
+        self.assertIn(
+            b'<input type="checkbox" data-cookie="djdtHistoryPanel" '
+            b'title="Enable for next and successive requests">',
+            response.content,
+        )
+        # Verify the a panel was rendered
+        self.assertIn(b"Response headers", response.content)
+
+    @override_settings(DEBUG_TOOLBAR_CONFIG={"RENDER_PANELS": False})
+    def test_load_panels(self):
+        """
+        Test that panels are not rendered during the request with
+        RENDER_PANELS=False
+        """
+        url = "/execute_sql/"
+        response = self.client.get(url)
+        self.assertIn(b'id="djDebug"', response.content)
+        # Verify the store id is included.
+        self.assertIn(b"data-store-id", response.content)
+        # Verify the history panel was not disabled
+        self.assertNotIn(
+            b'<input type="checkbox" data-cookie="djdtHistoryPanel" '
+            b'title="Enable for next and successive requests">',
+            response.content,
+        )
+        # Verify the a panel was not rendered
+        self.assertNotIn(b"Response headers", response.content)
 
     def test_view_returns_template_response(self):
         response = self.client.get("/template_response/basic/")