def db_downgrade(step):
"""
Downgrades a DB to a previous version as specified with the `step`
:param step: number of downgrades to do
:return: None
"""
to_use = [_.strip('.sql') for _ in migration_files()]
# since it's a downgrade, a reverse of the migration is essential
to_use.reverse()
generate_migration_file()
dbd_query = anosql.from_path(MIGRATION_FILE, 'psycopg2')
try:
count = 0
for _ in to_use:
count += 1
if MySQLScheme.fetch_one(REVISION_EXISTS,
**{"args": {'revision': _}}):
MySQLScheme.commit(getattr(dbd_query, f"downgrade_{_}").sql)
LOGGER.info(f"successful downgrade: {_}")
if count == step:
break
except errors.ProgrammingError:
print("no more downgrade left")
def db_initialise():
"""
Create the migrations folder and DB table if they are non-existent
:return: None
"""
generate_migration_file()
if not MySQLScheme.fetch_one(IS_MIGRATION_TABLE,
**{"args": {'schema': SCHEMA}}):
with open(MIGRATION_FILE, 'r') as init_sql:
data = init_sql.read()
if f"CREATE TABLE IF NOT EXISTS {MIGRATION_TABLE}" not in data:
when = str(int(time.time()))
sql_file = os.path.join(MIGRATION_FOLDER, f"{when}.sql")
with open(sql_file, 'w') as save_sql:
up = MYSQL_MIGRATION_UP.format(f"upgrade-{when}", when,
MIGRATION_TABLE)
down = MYSQL_MIGRATION_DOWN.format(f"downgrade-{when}",
MIGRATION_TABLE)
save_sql.write("\n\n".join([up, down]))
LOGGER.info(f"migration file: "
f"{os.path.join('migrations', sql_file)}")
else:
when = re.findall('[0-9]+', data)[0]
generate_migration_file()
dbi_query = anosql.from_path(MIGRATION_FILE, 'psycopg2')
MySQLScheme.commit(getattr(dbi_query, f"upgrade_{when}").sql)
LOGGER.info(f"initial successful migration: {when}")
def db_upgrade():
"""
Runs an upgrade on a DB using the generated `MIGRATION_FILE`
:return: None
"""
generate_migration_file()
dbu_query = anosql.from_path(MIGRATION_FILE, 'psycopg2')
for time_step in [_.strip('.sql') for _ in migration_files()]:
decide = MySQLScheme.fetch_one(REVISION_EXISTS,
**{"args": {'revision': time_step}})
if not decide:
MySQLScheme.commit(getattr(dbu_query, f"upgrade_{time_step}").sql)
LOGGER.info(f"successful migration: {time_step}")
else:
LOGGER.info(f'migration already exists: {time_step}')
