1 from __future__ import with_statement

     2 from alembic import context

     3 from sqlalchemy import engine_from_config, pool

     4 from logging.config import fileConfig

     5 

     6 import config as app_config

     7 import models

     8 

     9 # this is the Alembic Config object, which provides

    10 # access to the values within the .ini file in use.

    11 config = context.config

    12 

    13 # Interpret the config file for Python logging.

    14 # This line sets up loggers basically.

    15 fileConfig(config.config_file_name)

    16 

    17 # add your model's MetaData object here

    18 # for 'autogenerate' support

    19 # from myapp import mymodel

    20 # target_metadata = mymodel.Base.metadata

    21 target_metadata = models.Base.metadata

    22 

    23 # other values from the config, defined by the needs of env.py,

    24 # can be acquired:

    25 # my_important_option = config.get_main_option("my_important_option")

    26 # ... etc.

    27 

    28 

    29 def run_migrations_offline():

    30     """Run migrations in 'offline' mode.

    31 

    32     This configures the context with just a URL

    33     and not an Engine, though an Engine is acceptable

    34     here as well.  By skipping the Engine creation

    35     we don't even need a DBAPI to be available.

    36 

    37     Calls to context.execute() here emit the given string to the

    38     script output.

    39 

    40     """

    41     url = config.get_main_option("sqlalchemy.url")

    42     context.configure(url=url, target_metadata=target_metadata)

    43 

    44     with context.begin_transaction():

    45         context.run_migrations()

    46 

    47 

    48 def run_migrations_online():

    49     """Run migrations in 'online' mode.

    50 

    51     In this scenario we need to create an Engine

    52     and associate a connection with the context.

    53 

    54     """

    55     alembic_config = config.get_section(config.config_ini_section)

    56     alembic_config['sqlalchemy.url'] = app_config.CONN_STR

    57 

    58     engine = engine_from_config(

    59         alembic_config,

    60         prefix='sqlalchemy.',

    61         poolclass=pool.NullPool)

    62 

    63     connection = engine.connect()

    64     context.configure(

    65         connection=connection,

    66         target_metadata=target_metadata

    67     )

    68 

    69     try:

    70         with context.begin_transaction():

    71             context.run_migrations()

    72     finally:

    73         connection.close()

    74 

    75 if context.is_offline_mode():

    76     run_migrations_offline()

    77 else:

    78     run_migrations_online()