env Namespace Reference

Functions
def	run_migrations_offline ()
def	run_migrations_online ()

Variables
	Base = declarative_base(metadata=meta)
	config = context.config
	logger = logging.getLogger('alembic.runtime.setup')
	meta
	below block is needed for mssql More...
	target_metadata = None

Function Documentation

run_migrations_offline()

def env.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.

Definition at line 45 of file env.py.

Referenced by run_migrations_online().

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()

run_migrations_online()

def env.run_migrations_online

(

)

Run migrations in 'online' mode.

In this scenario we need to create an Engine
and associate a connection with the context.

Definition at line 63 of file env.py.

References run_migrations_offline().

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.

 """
 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.')

 connection = engine.connect()
 context.configure(
 connection=connection,
 target_metadata=target_metadata,
 version_table='alembic_version'
 )

 script_location = config.get_main_option('script_location')
 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.
 """
 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)

 try:
 with context.begin_transaction():
 context.run_migrations()
 finally:
 connection.close()

Variable Documentation

Base

Base = declarative_base(metadata=meta)

Definition at line 29 of file env.py.

config

config = context.config

Definition at line 12 of file env.py.

logger

logger = logging.getLogger('alembic.runtime.setup')

Definition at line 31 of file env.py.

meta

meta

below block is needed for mssql

Definition at line 22 of file env.py.

Referenced by nroot(), send_trunk(), and socket_process_helper().

target_metadata

target_metadata = None

Definition at line 36 of file env.py.