from __future__ import with_statement
from alembic import context
from sqlalchemy import engine_from_config, pool
from logging.config import fileConfig
import os
import sys

# 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.
fileConfig(config.config_file_name)

# add your model's MetaData object here
# for 'autogenerate' support
# from myapp import mymodel
# target_metadata = mymodel.Base.metadata
target_metadata = None

# 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 get_app_config(key):
    opath = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
    if opath not in sys.path:
        sys.path.insert(0, opath)
        
    from service import app as app_module
    app = app_module.create_app()
    
    print 'Getting actual config for', key, app.config.get(key)
    return app.config.get(key)

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.

    """
    cfg = config.get_section(config.config_ini_section)
    if 'use_flask_db_url' in cfg and cfg['use_flask_db_url'] == 'true':
        cfg['sqlalchemy.url'] = get_app_config('SQLALCHEMY_BINDS')['metrics']
    
    
    engine = engine_from_config(
                cfg,
                prefix='sqlalchemy.',
                poolclass=pool.NullPool)

    connection = engine.connect()
    context.configure(
                connection=connection,
                target_metadata=target_metadata
                )

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

if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()


from __future__ import with_statement
from alembic import context
from sqlalchemy import engine_from_config, pool
from logging.config import fileConfig
import os
import sys

# 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.
fileConfig(config.config_file_name)

# add your model's MetaData object here
# for 'autogenerate' support
# from myapp import mymodel
# target_metadata = mymodel.Base.metadata
target_metadata = None

# 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 get_app_config(key):
    opath = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
    if opath not in sys.path:
        sys.path.insert(0, opath)
        
    from service import app as app_module
    app = app_module.create_app()
    
    print 'Getting actual config for', key, app.config.get(key)
    return app.config.get(key)

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.

    """
    cfg = config.get_section(config.config_ini_section)
    if 'use_flask_db_url' in cfg and cfg['use_flask_db_url'] == 'true':
        cfg['sqlalchemy.url'] = get_app_config('SQLALCHEMY_DATABASE_URI')
    
    
    engine = engine_from_config(
                cfg,
                prefix='sqlalchemy.',
                poolclass=pool.NullPool)

    connection = engine.connect()
    context.configure(
                connection=connection,
                target_metadata=target_metadata
                )

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

if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()


Update env.py