Allow the healthcheck middleware to provide more detailed responses

It can be quite useful to have admin endpoints for healthcheck
middleware provide more information about the health of the system.

To enable this kind of information this initial step starts to
add a jinja2 template that will produce the existing simple case
by default, but when setup with detailed mode it can then produce
more information about which checks were performed and there results.

It can be expanded in the future to provide more information as
desired (possibly showing more useful application level info when
in detailed mode).

Closes-Bug: #1494531

Change-Id: I9c6dae848985d950c3cf6798695c7669eb245ccb

1 files changed, 26 insertions, 4 deletions

diff --git a/oslo_middleware/tests/test_healthcheck.py b/oslo_middleware/tests/test_healthcheck.py
index 13aa5fd..b516d0c 100644
--- a/oslo_middleware/tests/test_healthcheck.py
+++ b/oslo_middleware/tests/test_healthcheck.py
@@ -28,12 +28,17 @@ class HealthcheckTests(test_base.BaseTestCase):
     def application(req):
         return 'Hello, World!!!'
 
-    def _do_test(self, conf={}, path='/healthcheck',
-                 expected_code=webob.exc.HTTPOk.code,
-                 expected_body=b''):
+    def _do_test_request(self, conf={}, path='/healthcheck',
+                         accept='text/plain'):
         self.app = healthcheck.Healthcheck(self.application, conf)
-        req = webob.Request.blank(path)
+        req = webob.Request.blank(path, accept=accept)
         res = req.get_response(self.app)
+        return res
+
+    def _do_test(self, conf={}, path='/healthcheck',
+                 expected_code=webob.exc.HTTPOk.code,
+                 expected_body=b'', accept='text/plain'):
+        res = self._do_test_request(conf=conf, path=path, accept=accept)
         self.assertEqual(expected_code, res.status_int)
         self.assertEqual(expected_body, res.body)
 
@@ -69,6 +74,14 @@ class HealthcheckTests(test_base.BaseTestCase):
         self._do_test(conf, expected_body=b'OK')
         self.assertIn('disable_by_file', self.app._backends.names())
 
+    def test_disablefile_enabled_html_detailed(self):
+        conf = {'backends': 'disable_by_file',
+                'disable_by_file_path': '/foobar', 'detailed': True}
+        res = self._do_test_request(conf, accept="text/html")
+        self.assertIn(b'Result of 1 checks:', res.body)
+        self.assertIn(b'<TD>OK</TD>', res.body)
+        self.assertEqual(webob.exc.HTTPOk.code, res.status_int)
+
     def test_disablefile_disabled(self):
         filename = self.create_tempfiles([('test', 'foobar')])[0]
         conf = {'backends': 'disable_by_file',
@@ -78,6 +91,15 @@ class HealthcheckTests(test_base.BaseTestCase):
                       expected_body=b'DISABLED BY FILE')
         self.assertIn('disable_by_file', self.app._backends.names())
 
+    def test_disablefile_disabled_html_detailed(self):
+        filename = self.create_tempfiles([('test', 'foobar')])[0]
+        conf = {'backends': 'disable_by_file',
+                'disable_by_file_path': filename, 'detailed': True}
+        res = self._do_test_request(conf, accept="text/html")
+        self.assertIn(b'<TD>DISABLED BY FILE</TD>', res.body)
+        self.assertEqual(webob.exc.HTTPServiceUnavailable.code,
+                         res.status_int)
+
     def test_two_backends(self):
         filename = self.create_tempfiles([('test', 'foobar')])[0]
         conf = {'backends': 'disable_by_file,disable_by_file',