text: # Copyright 2013-2019 CERN for the benefit of the ATLAS collaboration.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #    http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  #
  # Authors:
  # - Martin Barisits <martin.barisits@cern.ch>, 2019
  # - Mario Lassnig <mario.lassnig@cern.ch>, 2019
  
  ''' add comments column for subscriptions_history '''
  
  import sqlalchemy as sa
  
  from alembic import context
  from alembic.op import add_column, drop_column
  
  
  # Alembic revision identifiers
  revision = 'b8caac94d7f0'
  down_revision = '8523998e2e76'
  
  
  def upgrade():
      '''
      Upgrade the database to this revision
      '''
  
      if context.get_context().dialect.name in ['oracle', 'mysql', 'postgresql']:
          schema = context.get_context().version_table_schema if context.get_context().version_table_schema else ''
          add_column('subscriptions_history', sa.Column('comments', sa.String(4000)), schema=schema)
  
  
  def downgrade():
      '''
      Downgrade the database to the previous revision
      '''
  
      if context.get_context().dialect.name in ['oracle', 'mysql', 'postgresql']:
          schema = context.get_context().version_table_schema if context.get_context().version_table_schema else ''
          drop_column('subscriptions_history', 'comments', schema=schema)
  