diagnostics: Use AppView for app page

Tests:

- Enable/disable button is not present.

- Diagnostics menu item is not present.

- Page shows 'Running diagnostics' button when diagnostics are not running.

- Page shows progress bar and results when diagnostics are running/completed.

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

plinth/modules/diagnostics/__init__.py

@@ -41,6 +41,8 @@ class DiagnosticsApp(app_module.App):
 
     _version = 1
 
+    can_be_disabled = False
+
     def __init__(self):
         """Create components for the app."""
         super().__init__()

plinth/modules/diagnostics/templates/diagnostics.html

@@ -8,7 +8,7 @@
 
 {% block configuration %}
 
-  {% if not is_running %}
+  {% if not is_task_running %}
     <form class="form form-run-diagnostics" method="post"
           action="{% url 'diagnostics:index' %}">
       {% csrf_token %}

plinth/modules/diagnostics/urls.py

@@ -8,7 +8,8 @@ from django.urls import re_path
 from . import views
 
 urlpatterns = [
-    re_path(r'^sys/diagnostics/$', views.index, name='index'),
+    re_path(r'^sys/diagnostics/$', views.DiagnosticsView.as_view(),
+            name='index'),
     re_path(r'^sys/diagnostics/(?P<app_id>[1-9a-z\-_]+)/$', views.diagnose_app,
             name='app'),
 ]

plinth/modules/diagnostics/views.py

@@ -5,33 +5,44 @@ FreedomBox app for running diagnostics.
 
 import logging
 
-from django.http import Http404
+from django.http import Http404, HttpResponseRedirect
 from django.template.response import TemplateResponse
+from django.urls import reverse
 from django.utils.translation import gettext_lazy as _
 from django.views.decorators.http import require_POST
 
 from plinth.app import App
 from plinth.modules import diagnostics
+from plinth.views import AppView
 
 logger = logging.getLogger(__name__)
 
 
-def index(request):
-    """Serve the index page"""
-    if request.method == 'POST' and not diagnostics.running_task:
-        diagnostics.start_task()
+class DiagnosticsView(AppView):
+    """Diagnostics app page."""
 
-    is_running = diagnostics.running_task is not None
-    with diagnostics.results_lock:
-        results = diagnostics.current_results
+    app_id = 'diagnostics'
+    template_name = 'diagnostics.html'
 
-    return TemplateResponse(
-        request, 'diagnostics.html', {
-            'app_info': App.get('diagnostics').info,
-            'is_running': is_running,
-            'results': results,
-            'refresh_page_sec': 3 if is_running else None
-        })
+    def post(self, request):
+        """Start diagnostics."""
+        if not diagnostics.running_task:
+            diagnostics.start_task()
+
+        return HttpResponseRedirect(reverse('diagnostics:index'))
+
+    def get_context_data(self, **kwargs):
+        """Return additional context for rendering the template."""
+        is_task_running = diagnostics.running_task is not None
+        with diagnostics.results_lock:
+            results = diagnostics.current_results
+
+        context = super().get_context_data(**kwargs)
+        context['has_diagnostics'] = False
+        context['is_task_running'] = is_task_running
+        context['results'] = results
+        context['refresh_page_sec'] = 3 if is_task_running else None
+        return context
 
 
 @require_POST