Files
asterisk/contrib/ast-db-manage/env.py
Sean Bright a07b5ca39e alembic: Fix compatibility with SQLAlchemy 2.0+.
SQLAlchemy 2.0 changed the way that commits/rollbacks are handled
causing the final `UPDATE` to our `alembic_version_<whatever>` tables
to be rolled back instead of committed.

We now use one connection to determine which
`alembic_version_<whatever>` table to use and another to run the
actual migrations. This prevents the erroneous rollback.

This change is compatible with both SQLAlchemy 1.4 and 2.0.

(cherry picked from commit 1944c9d72e)
2024-05-09 13:48:09 +00:00

151 lines
5.1 KiB
Python

from __future__ import with_statement
from alembic import context
from alembic.script import ScriptDirectory
from alembic.operations import Operations
from sqlalchemy import engine_from_config, pool, MetaData
from sqlalchemy.ext.declarative import declarative_base
from logging.config import fileConfig
import logging
# this is the Alembic Config object, which provides
# access to the values within the .ini file in use.
config = context.config
# Interpret the config file for Python logging.
# This line sets up loggers basically.
try:
fileConfig(config.config_file_name)
except:
pass
## below block is needed for mssql
meta = MetaData(naming_convention = {
"ix": 'ix_%(column_0_label)s',
"uq": "uq_%(table_name)s_%(column_0_name)s",
"ck": "ck_%(table_name)s_%(column_0_name)s_%(constraint_name)s",
"fk": "fk_%(table_name)s_%(column_0_name)s_%(referred_table_name)s",
"pk": "pk_%(table_name)s"
})
Base = declarative_base(metadata=meta)
logger = logging.getLogger('alembic.runtime.setup')
# add your model's MetaData object here
# for 'autogenerate' support
# from myapp import mymodel
# target_metadata = mymodel.Base.metadata
target_metadata = None
#Comment above line and uncomment below line for mssql
#target_metadata = Base.metadata
# other values from the config, defined by the needs of env.py,
# can be acquired:
# my_important_option = config.get_main_option("my_important_option")
# ... etc.
def run_migrations_offline():
"""Run migrations in 'offline' mode.
This configures the context with just a URL
and not an Engine, though an Engine is acceptable
here as well. By skipping the Engine creation
we don't even need a DBAPI to be available.
Calls to context.execute() here emit the given string to the
script output.
"""
url = config.get_main_option("sqlalchemy.url")
context.configure(url=url,target_metadata=target_metadata)
with context.begin_transaction():
context.run_migrations()
def run_migrations_online():
"""Run migrations in 'online' mode.
In this scenario we need to create an Engine
and associate a connection with the context.
"""
script_location = config.get_main_option('script_location')
engine = engine_from_config(
config.get_section(config.config_ini_section),
prefix='sqlalchemy.',
poolclass=pool.NullPool)
logger.info('Testing for an old alembic_version table.')
with engine.connect() as connection:
context.configure(
connection=connection,
target_metadata=target_metadata
)
found = False
mc = context.get_context()
current_db_revision = mc.get_current_revision()
script = ScriptDirectory.from_config(config)
""" If there was an existing alembic_version table, we need to
check that it's current revision is in the history for the tree
we're working with.
"""
for x in script.iterate_revisions('head', 'base'):
if x.revision == current_db_revision:
""" An alembic_versions table was found and it belongs to
this alembic tree
"""
logger.info(
('An old alembic_version table at revision %s was '
'found for %s. Renaming to alembic_version_%s.'),
current_db_revision, script_location,
script_location)
op = Operations(mc)
try:
with context.begin_transaction():
op.rename_table(
'alembic_version', 'alembic_version_%s'
% script_location)
found = True
except:
logger.error(('Unable to rename alembic_version to '
'alembic_version_%s.'),
script_location)
connection.close()
return
break
if not found:
logger.info('Didn\'t find an old alembic_version table.')
logger.info('Trying alembic_version_%s.' % script_location)
""" We MAY have an alembic_version table that doesn't belong to
this tree but if we still don't have an alembic_version_<tree>
table, alembic will create it.
"""
with engine.connect() as connection:
context.configure(
connection=connection,
target_metadata=target_metadata,
version_table='alembic_version_' + script_location
)
mc = context.get_context()
current_db_revision = mc.get_current_revision()
if current_db_revision:
logger.info(
'Using the alembic_version_%s table at revision %s.',
script_location, current_db_revision)
else:
logger.info('Creating new alembic_version_%s table.',
script_location)
with context.begin_transaction():
context.run_migrations()
if context.is_offline_mode():
run_migrations_offline()
else:
run_migrations_online()