superset/migrations/versions/33d996bcc382_update_slice_model.py

from alembic import op
import sqlalchemy as sa
from superset import db
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import (
    Column, Integer, String)

"""update slice model

Revision ID: 33d996bcc382
Revises: 41f6a59a61f2
Create Date: 2016-09-07 23:50:59.366779

"""

# revision identifiers, used by Alembic.
revision = '33d996bcc382'
down_revision = '41f6a59a61f2'

Base = declarative_base()


class Slice(Base):
    """Declarative class to do query in upgrade"""
    __tablename__ = 'slices'
    id = Column(Integer, primary_key=True)
    datasource_id = Column(Integer)
    druid_datasource_id = Column(Integer)
    table_id = Column(Integer)
    datasource_type = Column(String(200))


def upgrade():
    bind = op.get_bind()
    op.add_column('slices', sa.Column('datasource_id', sa.Integer()))
    session = db.Session(bind=bind)

    for slc in session.query(Slice).all():
        if slc.druid_datasource_id:
            slc.datasource_id = slc.druid_datasource_id
        if slc.table_id:
            slc.datasource_id = slc.table_id
        session.merge(slc)
        session.commit()
    session.close()


def downgrade():
    bind = op.get_bind()
    session = db.Session(bind=bind)
    for slc in session.query(Slice).all():
        if slc.datasource_type == 'druid':
            slc.druid_datasource_id = slc.datasource_id
        if slc.datasource_type == 'table':
            slc.table_id = slc.datasource_id
        session.merge(slc)
        session.commit()
    session.close()
    op.drop_column('slices', 'datasource_id')