Migration script for database changes

migrations/versions/8b976945a54e_.py

@@ -0,0 +1,30 @@
+"""empty message
+
+Revision ID: 8b976945a54e
+Revises: c872232ebdcb
+Create Date: 2021-04-18 11:42:41.894378
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '8b976945a54e'
+down_revision = 'c872232ebdcb'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    op.add_column('workflow', sa.Column('user_id', sa.String(), nullable=True))
+    op.add_column('workflow_spec', sa.Column('standalone', sa.String(), default=False))
+    op.execute("UPDATE workflow_spec SET standalone=False WHERE standalone is null;")
+    op.execute("ALTER TABLE task_event ALTER COLUMN study_id DROP NOT NULL")
+
+
+def downgrade():
+    op.execute("UPDATE workflow SET user_id=NULL WHERE user_id is not NULL")
+    op.drop_column('workflow', 'user_id')
+    op.drop_column('workflow_spec', 'standalone')
+    op.execute("ALTER TABLE task_event ALTER COLUMN study_id SET NOT NULL ")