Add migration

migrations/versions/aa6d21889d22_.py

@@ -0,0 +1,34 @@
+"""empty message
+
+Revision ID: aa6d21889d22
+Revises: b254f55eadd2
+Create Date: 2018-05-29 18:28:28.540416
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = 'aa6d21889d22'
+down_revision = 'b254f55eadd2'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.alter_column('user', 'password',
+               existing_type=sa.VARCHAR(length=255),
+               nullable=True,
+               existing_server_default=sa.text("''"))
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.alter_column('user', 'password',
+               existing_type=sa.VARCHAR(length=255),
+               nullable=False,
+               existing_server_default=sa.text("''"))
+    # ### end Alembic commands ###