Merge lp:~stub/launchpad/replication into lp:launchpad

[Stuart Bishop]

[no-qa] [r=stub] Slony-I 2.0 compatibility and migration script for staging tests.

= Summary =

We are migrating to Slony-I 2.0

== Proposed fix ==

Generate slonik scripts to do migration.

Migration process:

• Run generate_migration.py to generate slonik scripts
• Inspect mig_* slonik scripts for correctness
• Put SSO into read-only mode (no db access or standalone db?).
• Shutdown pgbouncer
• Confirm no connections to any databases apart from slony
• slonik mig_uninstall.sk
• Shutdown slon daemons
• Shutdown PostgreSQL on all servers
• Update slon packages on all servers
• Startup PostgreSQL on all servers
• Start slon daemons on wildcherry
• slonik mig_rebuild.sk
• Startup pgbouncer
• Restore SSO server

== Pre-implementation notes ==

== Implementation details ==

== Tests ==

Testing of generated scripts done locally, next up staging.

== Demo and Q/A ==

= Launchpad lint =

Checking for conflicts and issues in changed files.

Linting changed files:
  database/schema/upgrade.py
  database/replication/generate_migration.py
  database/replication/helpers.py

./database/schema/upgrade.py
      13: '_pythonpath' imported but unused
./database/replication/generate_migration.py
     188: local variable 'origin_node' is assigned to but never used
      13: '_pythonpath' imported but unused
      19: 'config' imported but unused
      65: E261 at least two spaces before inline comment
     121: E231 missing whitespace after ','
     159: E225 missing whitespace around operator
     176: E225 missing whitespace around operator

[Stuart Bishop (stub)]

Run-once script

review: Approve