Fix text/plain mime type with healthcheck endpoint

Previously if you used an accept header of text/plain when querying the healthcheck endpoint, you would get a 406 Not Acceptable response.
This patch corrects that to allow requesting the healthcheck document in text format.

Change-Id: I0e2d06b02c06b8c77fb1c2f94207d422066a0c6d

octavia/api/root_controller.py

@@ -39,7 +39,7 @@ class RootController(object):
 
     # Run the oslo middleware healthcheck for /healthcheck
     @pecan_expose('json')
-    @pecan_expose(content_type='plain/text')
+    @pecan_expose(content_type='text/plain')
     @pecan_expose(content_type='text/html')
     def healthcheck(self):  # pylint: disable=inconsistent-return-statements
         if CONF.api_settings.healthcheck_enabled:

octavia/tests/functional/api/test_healthcheck.py

@@ -118,6 +118,20 @@ class TestHealthCheck(base_db_test.OctaviaDBTestBase):
         self.assertEqual(200, response.status_code)
         self.assertEqual('OK', response.text)
 
+    def test_healthcheck_get_text_plain(self):
+        self.conf.config(group='healthcheck', detailed=False)
+        response = self._get(self._get_enabled_app(), '/healthcheck',
+                             headers={'Accept': 'text/plain'})
+        self.assertEqual(200, response.status_code)
+        self.assertEqual('OK', response.text)
+
+    def test_healthcheck_get_text_plain_detailed(self):
+        self.conf.config(group='healthcheck', detailed=True)
+        response = self._get(self._get_enabled_app(), '/healthcheck',
+                             headers={'Accept': 'text/plain'})
+        self.assertEqual(200, response.status_code)
+        self.assertEqual('OK', response.text)
+
     def test_healthcheck_get_json(self):
         self.conf.config(group='healthcheck', detailed=False)
         response = self._get(self._get_enabled_app(), '/healthcheck',

releasenotes/notes/Fix-healthcheck-text-plain-mime-type-134485abb8bcea0c.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Fixed the ability to use the 'text/plain' mime type with the healthcheck
+    endpoint.