migrations/env.py

   1 import logging.config
   2
   3 from alembic import context
   4 from flask import current_app
   5 from sqlalchemy import engine_from_config, pool
   6
   7 from indico.core.db import db
   8 from indico.core.db.sqlalchemy.util.session import update_session_options
   9 from indico.core.db.sqlalchemy.util.models import import_all_models
  10
  11
  12 # Ensure all our models are imported
  13 import_all_models()
  14
  15 # this is the Alembic Config object, which provides
  16 # access to the values within the .ini file in use.
  17 config = context.config
  18 logging.config.fileConfig(config.config_file_name)
  19
  20 config.set_main_option('sqlalchemy.url', current_app.config.get('SQLALCHEMY_DATABASE_URI'))
  21 target_metadata = current_app.extensions['migrate'].db.metadata
  22
  23 # Get rid of the ZODB transaction manager
  24 update_session_options(db)
  25
  26
  27 def _include_symbol(tablename, schema):
  28     # We ignore plugin tables in migrations
  29     if schema and schema.startswith('plugin_'):
  30         return False
  31     return not tablename.startswith('alembic_version_')
  32
  33
  34 def _render_item(type_, obj, autogen_context):
  35     if hasattr(obj, 'info') and obj.info.get('alembic_dont_render'):
  36         return None
  37     func = getattr(obj, 'alembic_render_' + type_, None)
  38     if func is None:
  39         return False
  40     return func(autogen_context)
  41
  42
  43 def run_migrations_offline():
  44     """Run migrations in 'offline' mode.
  45
  46     This configures the context with just a URL
  47     and not an Engine, though an Engine is acceptable
  48     here as well.  By skipping the Engine creation
  49     we don't even need a DBAPI to be available.
  50
  51     Calls to context.execute() here emit the given string to the
  52     script output.
  53
  54     """
  55     url = config.get_main_option('sqlalchemy.url')
  56     context.configure(url=url, target_metadata=target_metadata, include_schemas=True,
  57                       version_table_schema='public', include_symbol=_include_symbol, render_item=_render_item)
  58
  59     with context.begin_transaction():
  60         context.run_migrations()
  61
  62
  63 def run_migrations_online():
  64     """Run migrations in 'online' mode.
  65
  66     In this scenario we need to create an Engine
  67     and associate a connection with the context.
  68
  69     """
  70     engine = engine_from_config(config.get_section(config.config_ini_section),
  71                                 prefix='sqlalchemy.',
  72                                 poolclass=pool.NullPool)
  73
  74     connection = engine.connect()
  75     context.configure(connection=connection, target_metadata=target_metadata, include_schemas=True,
  76                       version_table_schema='public', include_symbol=_include_symbol, render_item=_render_item)
  77
  78     try:
  79         with context.begin_transaction():
  80             context.run_migrations()
  81     finally:
  82         connection.close()
  83
  84
  85 if context.is_offline_mode():
  86     run_migrations_offline()
  87 else:
  88     run_migrations_online()