"""add_unique_constraint_external_id_to_user_table

Revision ID: 1fc97d27e260
Revises: dd2ee98d45e4
Create Date: 2022-03-10 14:13:47.249024

"""
from alembic import op
import sqlalchemy as sa


# revision identifiers, used by Alembic.
revision = '1fc97d27e260'
down_revision = 'dd2ee98d45e4'
branch_labels = None
depends_on = None


def upgrade():
    bind = op.get_bind()
    constraint_present = bind.execute('''
        select constraint_name from information_schema.constraint_column_usage
        where table_name = 'User' and constraint_name = 'uq_User_external_id'
    ''').fetchone()

    if constraint_present is None:
        op.create_unique_constraint('uq_User_external_id', 'User', ['external_id'])

    constraint_present = bind.execute('''
            select constraint_name from information_schema.constraint_column_usage
            where table_name = 'User' and constraint_name = 'uq_User_email'
        ''').fetchone()

    if constraint_present is None:
        op.create_unique_constraint('uq_User_email', 'User', ['email'])


def downgrade():
    op.drop_constraint(op.f('uq_User_external_id'), 'User', type_='unique')
    op.drop_constraint(op.f('uq_User_email'), 'User', type_='unique')