"""add label and uuid

Revision ID: 3aec56269d7e

Revises: 37eaf74e46b

Create Date: 2014-10-28 17:17:19.017259

"""

# revision identifiers, used by Alembic.

revision = '3aec56269d7e'

down_revision = '37eaf74e46b'

import uuid

from alembic import op

import sqlalchemy as sa

from sqlalchemy.dialects import postgresql

def upgrade():

    op.add_column('event_session', sa.Column('label', sa.String(length=2048), nullable=True))

    op.add_column('event_session', sa.Column('uuid', postgresql.UUID(), nullable=True))

    op.create_unique_constraint(None, 'event_session', ['uuid'])

    event_session = sa.sql.table('event_session',

        sa.sql.column('id', sa.Integer),

        sa.sql.column('uuid', postgresql.UUID)

    )

    connection = op.get_bind()

    for r in connection.execute(event_session.select()):

        op.execute(event_session.update().values({'uuid':str(uuid.uuid4())}).where(event_session.c.id == r['id']))

    op.alter_column('event_session', 'uuid',

           existing_type=postgresql.UUID(),

           nullable=False)

def downgrade():

    ### commands auto generated by Alembic - please adjust! ###

    op.drop_constraint("event_session_uuid_key", 'event_session')

    op.drop_column('event_session', 'uuid')

    op.drop_column('event_session', 'label')

    ### end Alembic commands ###