- return indexes_added
-
-
-def remove_deprecated_indexes(database, deprecated_indexes=DEPRECATED_INDEXES):
- """
- Remove any deprecated indexes from the database.
-
- Args:
- - database: pymongo or mongokit database instance.
- - deprecated_indexes: the indexes to deprecate in the pattern of:
- {'collection_name': {
- 'identifier': {
- 'index': [index_foo_goes_here],
- 'unique': True}}
-
- (... although we really only need the 'identifier' here, as the
- rest of the information isn't used in this case. But it's kept
- around so we can remember what it was)
-
- Returns:
- A list of indexes removed in form ('collection', 'index_name')
- """
- indexes_removed = []
-
- for collection_name, indexes in deprecated_indexes.iteritems():
- collection = database[collection_name]
- collection_indexes = collection.index_information().keys()
-
- for index_name, index_data in indexes.iteritems():
- if index_name in collection_indexes:
- collection.drop_index(index_name)
-
- indexes_removed.append((collection_name, index_name))
-
- return indexes_removed
-
-
-#################
-# Migration tools
-#################
-
-# The default migration registry...
-#
-# Don't set this yourself! RegisterMigration will automatically fill
-# this with stuff via decorating methods in migrations.py
-
-class MissingCurrentMigration(Exception): pass
-
-
-MIGRATIONS = {}
-
-
-class RegisterMigration(object):
- """
- Tool for registering migrations
-
- Call like:
-
- @RegisterMigration(33)
- def update_dwarves(database):
- [...]
-
- This will register your migration with the default migration
- registry. Alternately, to specify a very specific
- migration_registry, you can pass in that as the second argument.
-
- Note, the number of your migration should NEVER be 0 or less than
- 0. 0 is the default "no migrations" state!
- """
- def __init__(self, migration_number, migration_registry=MIGRATIONS):
- assert migration_number > 0, "Migration number must be > 0!"
- assert not migration_registry.has_key(migration_number), \
- "Duplicate migration numbers detected! That's not allowed!"
-
- self.migration_number = migration_number
- self.migration_registry = migration_registry
-
- def __call__(self, migration):
- self.migration_registry[self.migration_number] = migration
- return migration
-
-
-class MigrationManager(object):
- """
- Migration handling tool.
-
- Takes information about a database, lets you update the database
- to the latest migrations, etc.
- """
- def __init__(self, database, migration_registry=MIGRATIONS):
- """
- Args:
- - database: database we're going to migrate
- - migration_registry: where we should find all migrations to
- run
- """
- self.database = database
- self.migration_registry = migration_registry
- self._sorted_migrations = None
-
- def _ensure_current_migration_record(self):
- """
- If there isn't a database[u'app_metadata'] mediagoblin entry
- with the 'current_migration', throw an error.
- """
- if self.database_current_migration() is None:
- raise MissingCurrentMigration(
- "Tried to call function which requires "
- "'current_migration' set in database")
-
- @property
- def sorted_migrations(self):
- """
- Sort migrations if necessary and store in self._sorted_migrations
- """
- if not self._sorted_migrations:
- self._sorted_migrations = sorted(
- self.migration_registry.items(),
- # sort on the key... the migration number
- key=lambda migration_tuple: migration_tuple[0])
-
- return self._sorted_migrations
-
- def latest_migration(self):
- """
- Return a migration number for the latest migration, or 0 if
- there are no migrations.
- """
- if self.sorted_migrations:
- return self.sorted_migrations[-1][0]
- else:
- # If no migrations have been set, we start at 0.
- return 0
-
- def set_current_migration(self, migration_number):
- """
- Set the migration in the database to migration_number
- """
- # Add the mediagoblin migration if necessary
- self.database[u'app_metadata'].update(
- {u'_id': u'mediagoblin'},
- {u'$set': {u'current_migration': migration_number}},
- upsert=True)
-
- def install_migration_version_if_missing(self):
- """
- Sets the migration to the latest version if no migration
- version at all is set.
- """
- mgoblin_metadata = self.database[u'app_metadata'].find_one(
- {u'_id': u'mediagoblin'})
- if not mgoblin_metadata:
- latest_migration = self.latest_migration()
- self.set_current_migration(latest_migration)
-
- def database_current_migration(self):
- """
- Return the current migration in the database.
- """
- mgoblin_metadata = self.database[u'app_metadata'].find_one(
- {u'_id': u'mediagoblin'})
- if not mgoblin_metadata:
- return None
- else:
- return mgoblin_metadata[u'current_migration']
-
- def database_at_latest_migration(self):
- """
- See if the database is at the latest migration.
- Returns a boolean.
- """
- current_migration = self.database_current_migration()
- return current_migration == self.latest_migration()
-
- def migrations_to_run(self):
- """
- Get a list of migrations to run still, if any.
-
- Note that calling this will set your migration version to the
- latest version if it isn't installed to anything yet!
- """
- self._ensure_current_migration_record()
-
- db_current_migration = self.database_current_migration()
-
- return [
- (migration_number, migration_func)
- for migration_number, migration_func in self.sorted_migrations
- if migration_number > db_current_migration]
-
- def migrate_new(self, pre_callback=None, post_callback=None):
- """
- Run all migrations.
-
- Includes two optional args:
- - pre_callback: if called, this is a callback on something to
- run pre-migration. Takes (migration_number, migration_func)
- as arguments
- - pre_callback: if called, this is a callback on something to
- run post-migration. Takes (migration_number, migration_func)
- as arguments
- """
- # If we aren't set to any version number, presume we're at the
- # latest (which means we'll do nothing here...)
- self.install_migration_version_if_missing()
-
- for migration_number, migration_func in self.migrations_to_run():
- if pre_callback:
- pre_callback(migration_number, migration_func)
- migration_func(self.database)
- self.set_current_migration(migration_number)
- if post_callback:
- post_callback(migration_number, migration_func)