diff options
Diffstat (limited to 'src/lib/Bcfg2/Server/SchemaUpdater/Routines.py')
| -rw-r--r-- | src/lib/Bcfg2/Server/SchemaUpdater/Routines.py | 279 |
1 files changed, 0 insertions, 279 deletions
diff --git a/src/lib/Bcfg2/Server/SchemaUpdater/Routines.py b/src/lib/Bcfg2/Server/SchemaUpdater/Routines.py deleted file mode 100644 index 4fcf0e6bf..000000000 --- a/src/lib/Bcfg2/Server/SchemaUpdater/Routines.py +++ /dev/null @@ -1,279 +0,0 @@ -import logging -import traceback -from django.db.models.fields import NOT_PROVIDED -from django.db import connection, DatabaseError, backend, models -from django.core.management.color import no_style -from django.core.management.sql import sql_create -import django.core.management - -import Bcfg2.settings - -logger = logging.getLogger(__name__) - -def _quote(value): - """ - Quote a string to use as a table name or column - """ - return backend.DatabaseOperations().quote_name(value) - - -def _rebuild_sqlite_table(model): - """Sqlite doesn't support most alter table statments. This streamlines the - rebuild process""" - try: - cursor = connection.cursor() - table_name = model._meta.db_table - - # Build create staement from django - model._meta.db_table = "%s_temp" % table_name - sql, references = connection.creation.sql_create_model(model, no_style()) - columns = ",".join([_quote(f.column) \ - for f in model._meta.fields]) - - # Create a temp table - [cursor.execute(s) for s in sql] - - # Fill the table - tbl_name = _quote(table_name) - tmp_tbl_name = _quote(model._meta.db_table) - # Reset this - model._meta.db_table = table_name - cursor.execute("insert into %s(%s) select %s from %s;" % ( - tmp_tbl_name, - columns, - columns, - tbl_name)) - cursor.execute("drop table %s" % tbl_name) - - # Call syncdb to create the table again - django.core.management.call_command("syncdb", interactive=False, verbosity=0) - # syncdb closes our cursor - cursor = connection.cursor() - # Repopulate - cursor.execute('insert into %s(%s) select %s from %s;' % (tbl_name, - columns, - columns, - tmp_tbl_name)) - cursor.execute('DROP TABLE %s;' % tmp_tbl_name) - except DatabaseError: - logger.error("Failed to rebuild sqlite table %s" % table_name, exc_info=1) - raise UpdaterRoutineException - - -class UpdaterRoutineException(Exception): - pass - - -class UpdaterRoutine(object): - """Base for routines.""" - def __init__(self): - pass - - def __str__(self): - return __name__ - - def run(self): - """Called to execute the action""" - raise UpdaterRoutineException - - - -class AddColumns(UpdaterRoutine): - """ - Routine to add new columns to an existing model - """ - def __init__(self, model): - self.model = model - self.model_name = model.__name__ - - def __str__(self): - return "Add new columns for model %s" % self.model_name - - def run(self): - try: - cursor = connection.cursor() - except DatabaseError: - logger.error("Failed to connect to the db") - raise UpdaterRoutineException - - try: - desc = {} - for d in connection.introspection.get_table_description(cursor, - self.model._meta.db_table): - desc[d[0]] = d - except DatabaseError: - logger.error("Failed to get table description", exc_info=1) - raise UpdaterRoutineException - - for field in self.model._meta.fields: - if field.column in desc: - continue - logger.debug("Column %s does not exist yet" % field.column) - if field.default == NOT_PROVIDED: - logger.error("Cannot add a column with out a default value") - raise UpdaterRoutineException - - sql = "ALTER TABLE %s ADD %s %s NOT NULL DEFAULT " % ( - _quote(self.model._meta.db_table), - _quote(field.column), field.db_type(), ) - db_engine = Bcfg2.settings.DATABASES['default']['ENGINE'] - if db_engine == 'django.db.backends.sqlite3': - sql += _quote(field.default) - sql_values = () - else: - sql += '%s' - sql_values = (field.default, ) - try: - cursor.execute(sql, sql_values) - logger.debug("Added column %s to %s" % - (field.column, self.model._meta.db_table)) - except DatabaseError: - logger.error("Unable to add column %s" % field.column) - raise UpdaterRoutineException - - -class RebuildTable(UpdaterRoutine): - """ - Rebuild the table for an existing model. Use this if field types have changed. - """ - def __init__(self, model, columns): - self.model = model - self.model_name = model.__name__ - - if type(columns) == str: - self.columns = [columns] - elif type(columns) in (tuple, list): - self.columns = columns - else: - logger.error("Columns must be a str, tuple, or list") - raise UpdaterRoutineException - - - def __str__(self): - return "Rebuild columns for model %s" % self.model_name - - def run(self): - try: - cursor = connection.cursor() - except DatabaseError: - logger.error("Failed to connect to the db") - raise UpdaterRoutineException - - db_engine = Bcfg2.settings.DATABASES['default']['ENGINE'] - if db_engine == 'django.db.backends.sqlite3': - """ Sqlite is a special case. Altering columns is not supported. """ - _rebuild_sqlite_table(self.model) - return - - if db_engine == 'django.db.backends.mysql': - modify_cmd = 'MODIFY ' - else: - modify_cmd = 'ALTER COLUMN ' - - col_strings = [] - for column in self.columns: - col_strings.append("%s %s %s" % ( \ - modify_cmd, - _quote(column), - self.model._meta.get_field(column).db_type() - )) - - try: - cursor.execute('ALTER TABLE %s %s' % - (_quote(self.model._meta.db_table), ", ".join(col_strings))) - except DatabaseError: - logger.debug("Failed modify table %s" % self.model._meta.db_table) - raise UpdaterRoutineException - - - -class RemoveColumns(RebuildTable): - """ - Routine to remove columns from an existing model - """ - def __init__(self, model, columns): - super(RemoveColumns, self).__init__(model, columns) - - - def __str__(self): - return "Remove columns from model %s" % self.model_name - - def run(self): - try: - cursor = connection.cursor() - except DatabaseError: - logger.error("Failed to connect to the db") - raise UpdaterRoutineException - - try: - columns = [d[0] for d in connection.introspection.get_table_description(cursor, - self.model._meta.db_table)] - except DatabaseError: - logger.error("Failed to get table description", exc_info=1) - raise UpdaterRoutineException - - for column in self.columns: - if column not in columns: - logger.warning("Cannot drop column %s: does not exist" % column) - continue - - logger.debug("Dropping column %s" % column) - - db_engine = Bcfg2.settings.DATABASES['default']['ENGINE'] - if db_engine == 'django.db.backends.sqlite3': - _rebuild_sqlite_table(self.model) - else: - sql = "alter table %s drop column %s" % \ - (_quote(self.model._meta.db_table), _quote(column), ) - try: - cursor.execute(sql) - except DatabaseError: - logger.debug("Failed to drop column %s from %s" % - (column, self.model._meta.db_table)) - raise UpdaterRoutineException - - -class DropTable(UpdaterRoutine): - """ - Drop a table - """ - def __init__(self, table_name): - self.table_name = table_name - - def __str__(self): - return "Drop table %s" % self.table_name - - def run(self): - try: - cursor = connection.cursor() - cursor.execute('DROP TABLE %s' % _quote(self.table_name)) - except DatabaseError: - logger.error("Failed to drop table: %s" % - traceback.format_exc().splitlines()[-1]) - raise UpdaterRoutineException - - -class UpdaterCallable(UpdaterRoutine): - """Helper for routines. Basically delays execution""" - def __init__(self, fn): - self.fn = fn - self.args = [] - self.kwargs = {} - - def __call__(self, *args, **kwargs): - self.args = args - self.kwargs = kwargs - return self - - def __str__(self): - return self.fn.__name__ - - def run(self): - self.fn(*self.args, **self.kwargs) - -def updatercallable(fn): - """Decorator for UpdaterCallable. Use for any function passed - into the fixes list""" - return UpdaterCallable(fn) - - |