diagnostics: Individual module check framework

Each module will implement its own diagnostics.  The diagnostics module
will provide a common, standardized mechanism for running these
diagnostics.

plinth/modules/diagnostics/diagnostics.py

@@ -19,11 +19,14 @@
 Plinth module for running diagnostics
 """
 
+from django.http import Http404
 from django.template.response import TemplateResponse
 from gettext import gettext as _
+import importlib
 
 from plinth import actions
 from plinth import cfg
+from plinth import module_loader
 from plinth.errors import ActionError
 
 
@@ -55,3 +58,24 @@ def test(request):
                             {'title': _('Diagnostic Test'),
                              'diagnostics_output': output,
                              'diagnostics_error': error})
+
+def module(request, module_name):
+    """Return diagnostics for a particular module."""
+    found = False
+    for module_import_path in module_loader.loaded_modules:
+        if module_name == module_import_path.split('.')[-1]:
+            found = True
+            break
+
+    if not found:
+        raise Http404('Module does not exist or not loaded')
+
+    loaded_module = importlib.import_module(module_import_path)
+    results = []
+    if hasattr(loaded_module, 'diagnose'):
+        results = loaded_module.diagnose()
+
+    return TemplateResponse(request, 'diagnostics_module.html',
+                            {'title': _('Diagnostic Test'),
+                             'module_name': module_name,
+                             'results': results})

plinth/modules/diagnostics/templates/diagnostics_module.html

@@ -0,0 +1,52 @@
+{% extends 'base.html' %}
+{% comment %}
+#
+# This file is part of Plinth.
+#
+# 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/>.
+#
+{% endcomment %}
+
+{% block content %}
+
+<h2>Diagnostic Results</h2>
+
+<h3>Module: {{ module_name }}</h3>
+
+{% if results %}
+<div class="row">
+  <div class="col-sm-3">
+    <table class="table table-bordered table-striped">
+      <thead>
+        <tr>
+          <th>Test</th>
+          <th>Result</th>
+        </tr>
+      </thead>
+      <tbody>
+        {% for test, result in results %}
+        <tr>
+          <td>{{ test }}</td>
+          <td>{{ result }}</td>
+        </tr>
+        {% endfor %}
+      </tbody>
+    </table>
+  </div>
+</div>
+{% else %}
+<p>This module does not support diagnostics</p>
+{% endif %}
+
+{% endblock %}

plinth/modules/diagnostics/urls.py

@@ -26,4 +26,6 @@ urlpatterns = patterns(  # pylint: disable-msg=C0103
     'plinth.modules.diagnostics.diagnostics',
     url(r'^sys/diagnostics/$', 'index', name='index'),
     url(r'^sys/diagnostics/test/$', 'test', name='test'),
+    url(r'^sys/diagnostics/module/(?P<module_name>[a-z\-]+)/$', 'module',
+        name='module'),
     )