help: Make about page available to unauthenticated users

- This page will replace the rather large footer in the front page.

Tests:

- Log out. Visit the help about page. It is available without redirection to
login page. Version related alert is not shown.

- Log in. Visit the help about page. It is available. Version related alert is
shown.

Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

plinth/modules/help/templates/help_about.html

@@ -13,23 +13,25 @@
          class="main-graphic" />
   </p>
 
-  <div class="alert {% if new_version %}alert-warning{% else %}alert-success{% endif %}">
-    {% blocktrans trimmed %}
-      You are running {{ os_release }} and {{ box_name }} version {{ version }}.
-    {% endblocktrans %}
+  {% if version %}
+    <div class="alert {% if new_version %}alert-warning{% else %}alert-success{% endif %}">
+      {% blocktrans trimmed %}
+        You are running {{ os_release }} and {{ box_name }} version {{ version }}.
+      {% endblocktrans %}
 
-    {% if new_version %}
-      {% url 'upgrades:index' as upgrades_url %}
-      {% blocktrans trimmed %}
-        There is a new {{ box_name }} version
-        <a href="{{ upgrades_url }}">available</a>.
-      {% endblocktrans %}
-    {% else %}
-      {% blocktrans trimmed %}
-        {{ box_name }} is up to date.
-      {% endblocktrans %}
-    {% endif %}
-  </div>
+      {% if new_version %}
+        {% url 'upgrades:index' as upgrades_url %}
+        {% blocktrans trimmed %}
+          There is a new {{ box_name }} version
+          <a href="{{ upgrades_url }}">available</a>.
+        {% endblocktrans %}
+      {% else %}
+        {% blocktrans trimmed %}
+          {{ box_name }} is up to date.
+        {% endblocktrans %}
+      {% endif %}
+    </div>
+  {% endif %}
 
   <p>
     {% blocktrans trimmed %}

plinth/modules/help/tests/test_views.py

@@ -12,7 +12,7 @@ Pending: - status log
 import json
 import pathlib
 import subprocess
-from unittest.mock import patch
+from unittest.mock import Mock, patch
 
 import pytest
 from django import urls
@@ -113,11 +113,19 @@ def test_contribute_page(requests_get, decompress, apt_cache, rf):
 def test_about(_get_os_release, _is_newer_version_available, rf):
     """Test some expected items in about view."""
     about_url = urls.reverse('help:about')
-    response = views.about(rf.get(about_url))
+    request = rf.get(about_url)
+    request.user = Mock()
+    request.user.is_authenticated = True
+    response = views.about(request)
     assert _is_page(response)
     for item in ('version', 'new_version', 'os_release'):
         assert item in response.context_data
 
+    request.user.is_authenticated = False
+    response = views.about(request)
+    for item in ('version', 'new_version', 'os_release'):
+        assert item not in response.context_data
+
 
 # ---------------------------------------------------------------------------
 # Tests for serving the offline user guide ( the "manual")

plinth/modules/help/urls.py

@@ -4,6 +4,7 @@ URLs for the Help module
 """
 
 from django.urls import re_path
+from stronghold.decorators import public
 
 from plinth.utils import non_admin_view
 
@@ -11,7 +12,7 @@ from . import views
 
 urlpatterns = [
     re_path(r'^help/$', non_admin_view(views.index), name='index'),
-    re_path(r'^help/about/$', non_admin_view(views.about), name='about'),
+    re_path(r'^help/about/$', public(views.about), name='about'),
     re_path(r'^help/feedback/$', non_admin_view(views.feedback),
             name='feedback'),
     re_path(r'^help/support/$', non_admin_view(views.support), name='support'),

plinth/modules/help/views.py

@@ -95,12 +95,14 @@ def support(request):
 
 def about(request):
     """Serve the about page"""
-    context = {
-        'title': _('About {box_name}').format(box_name=_(cfg.box_name)),
-        'version': __version__,
-        'new_version': upgrades_views.is_newer_version_available(),
-        'os_release': upgrades_views.get_os_release()
-    }
+    context = {'title': _('About {box_name}').format(box_name=_(cfg.box_name))}
+    if request.user.is_authenticated:
+        context.update({
+            'version': __version__,
+            'new_version': upgrades_views.is_newer_version_available(),
+            'os_release': upgrades_views.get_os_release()
+        })
+
     return TemplateResponse(request, 'help_about.html', context)