Merge lp:~stub/charms/precise/postgresql/data-checksums into lp:charms/postgresql

[Stuart Bishop]

Data checksums are a new feature added to PostgreSQL 9.3 that cause the database to halt when corruption is detected.

I have elected to turn the feature on by default for all new PG 9.3 installations. Since release, I'm seeing more recommendations to use the feature. It seems particularly useful with Juju environments, where we are often using remote disk.

[lp:~stub/charms/precise/postgresql/data-checksums]

158. By Stuart Bishop on 2014-08-27

Merged test-upgrade-charm into data-checksums.

159. By Stuart Bishop on 2014-08-27

Merged test-upgrade-charm into data-checksums.

160. By Stuart Bishop on 2014-08-27

Merged test-upgrade-charm into data-checksums.

161. By Stuart Bishop on 2014-08-27

Merged test-upgrade-charm into data-checksums.

[Whit Morriss (whitmo)]

merged in https://code.launchpad.net/~stub/charms/precise/postgresql/integration/+merge/233666

=== modified file 'hooks/hooks.py'
--- hooks/hooks.py	2014-08-27 12:56:22 +0000
+++ hooks/hooks.py	2014-08-27 12:56:22 +0000
@@ -4,6 +4,7 @@
 from contextlib import contextmanager
 import commands
 import cPickle as pickle
+from distutils.version import StrictVersion
 import glob
 from grp import getgrnam
 import os.path
@@ -341,8 +342,17 @@
             "-e", hookenv.config('encoding')]
         if hookenv.config('listen_port'):
             create_cmd.extend(["-p", str(hookenv.config('listen_port'))])
-        create_cmd.append(pg_version())
+        version = pg_version()
+        create_cmd.append(version)
         create_cmd.append(hookenv.config('cluster_name'))
+
+        # With 9.3+, we make an opinionated decision to always enable
+        # data checksums. This seems to be best practice. We could
+        # turn this into a configuration item if there is need. There
+        # is no way to enable this option on existing clusters.
+        if StrictVersion(version) >= StrictVersion('9.3'):
+            create_cmd.extend(['--', '--data-checksums'])
+
         run(create_cmd)
         # Ensure SSL certificates exist, as we enable SSL by default.
         create_ssl_cert(os.path.join(