Merge lp:~wesmason/conn-check/configs-django-dev into lp:~ubuntuone-hackers/conn-check/configs

[Wes Mason]

Ignore path based database HOST values and set other values more flexibly for db engines

This adds greater flexibility to the checks generated for a django DATABASES value, ignoring path based hosts (e.g. unix socket FDs used for mysql/postgres), optionally sets the port/username/password depending on their presence (maintaining integer cast for port), and sets the checks for mysql/oracle as well as postgres (as these will be added to conn-check).

[James Westby (james-w)]

review: Needs Fixing

[lp:~wesmason/conn-check/configs-django-dev]

15. By Wes Mason on 2014-10-21

Add comment about skipping db file paths

[James Westby (james-w)]

review: Approve

=== modified file 'conn_check_configs/django.py'
--- conn_check_configs/django.py	2014-10-15 12:47:18 +0000
+++ conn_check_configs/django.py	2014-10-21 14:04:05 +0000
@@ -39,16 +39,36 @@
 
 def make_postgres_checks(settings, options):
     checks = []
+    engines = {
+        'django.db.backends.postgresql_psycopg2': 'postgres',
+        'django.db.backends.mysql': 'mysql',
+        'django.db.backends.oracle': 'oracle',
+    }
     for name, db in settings.get('DATABASES', {}).items():
-        if db.get('ENGINE') == 'django.db.backends.postgresql_psycopg2':
-            checks.append({
-                'type': 'postgres',
+        # We exclude hosts starting with a forward slash (/) as these are
+        # always socket filepaths for MySQL and PostgreSQL, see:
+        # https://docs.djangoproject.com/en/dev/ref/settings/#host
+        if db['ENGINE'] in engines and not str(db['HOST']).startswith('/'):
+            check = {
+                'type': engines[db['engine']],
                 'database': db.get('NAME', options.db_name),
                 'host': db['HOST'],
-                'port': int(db['PORT']),
-                'username': db['USER'],
-                'password': db['PASSWORD'],
-            })
+            }
+
+            port = db['PORT']
+            if port is not None:
+                check['port'] = int(port)
+
+            username = db['USER']
+            if username is not None:
+                check['username'] = username
+
+            password = db['PASSWORD']
+            if password is not None:
+                check['password'] = password
+
+            checks.append(check)
+
     return checks