Tie Oncall healthcheck to database availability (linkedin#320)

* Tie healthcheck to db availability

* add correct number of substitutions

* pin greenlet version

* update flake8 settings

setup.py

@@ -29,6 +29,8 @@
     install_requires=[
         'falcon==1.4.1',
         'falcon-cors',
+        'greenlet==0.4.16',
+        'asn1crypto==1.0.0',
         'gevent==1.4.0',
         'ujson',
         'sqlalchemy',

src/oncall/api/v0/ical_key_requester.py

@@ -34,7 +34,7 @@ def on_delete(req, resp, requester):
     if not (challenger == requester or check_ical_key_admin(challenger)):
         raise HTTPForbidden(
             'Unauthorized',
-            'Action not allowed: "%s" is not allowed to delete ical_keys of "%s"' % (challenger, ),
+            'Action not allowed: "%s" is not allowed to delete ical_keys of "%s"' % (challenger, requester),
         )
 
     invalidate_ical_key_by_requester(requester)

src/oncall/healthcheck.py

@@ -1,7 +1,8 @@
 # Copyright (c) LinkedIn Corporation. All rights reserved. Licensed under the BSD-2 Clause license.
 # See LICENSE in the project root for license information.
 
-from falcon import HTTPNotFound
+from falcon import HTTPNotFound, HTTPInternalServerError
+from . import db
 
 
 class HealthCheck(object):
@@ -21,6 +22,14 @@ def on_get(self, req, resp):
         if self.dummy_status:
             status = self.dummy_status
         else:
+            try:
+                connection = db.connect()
+                cursor = connection.cursor()
+                cursor.execute("SELECT VERSION();")
+                cursor.close()
+                connection.close()
+            except:
+                raise HTTPInternalServerError()
             try:
                 with open(self.path) as f:
                     status = f.readline().strip()

tox.ini

@@ -4,7 +4,7 @@ envlist = py27
 [flake8]
 exclude = .tox,./build
 filename = *.py
-ignore = E101,E741,W292,E722,E731,W503,W504
+ignore = E101,E741,W292,E722,E731,W503,W504,E402
 max-line-length = 160
 
 [testenv]