def getDiffMonkeyPatch(metadata, engine, excludeTables=None):
"""
Return differences of model against database.
:return: object which will evaluate to :keyword:`True` if there \
are differences else :keyword:`False`.
"""
db_metadata = sa.MetaData(engine, reflect=True)
# sqlite will include a dynamically generated 'sqlite_sequence' table if
# there are autoincrement sequences in the database; this should not be
# compared.
if engine.dialect.name == 'sqlite':
if 'sqlite_sequence' in db_metadata.tables:
db_metadata.remove(db_metadata.tables['sqlite_sequence'])
return schemadiff.SchemaDiff(metadata, db_metadata,
labelA='model',
labelB='database',
excludeTables=excludeTables)
def update_database_from_model():
"""Introspection the model and add missing columns in the database.
this function can be ran in setup_model after::
metadata.create_all()
"""
migrate_engine = settings.ENGINE()
migrate_connection = migrate_engine.connect()
from sqlalchemy.schema import MetaData
from migrate.versioning import schemadiff
from migrate.changeset import create_column
schema_diff = schemadiff.SchemaDiff(
metadata, MetaData(migrate_connection, reflect=True))
for table_name, difference in schema_diff.tables_different.items():
for column in difference.columns_missing_from_B:
LOGGER.warn('column %s missing in table %s' % (column, table_name))
table = metadata.tables[table_name]
create_column(column, table)
