Adds new job_status table and FK to jobs.

This will replace the job_status enum type.

migrations/versions/0048_job_scheduled_time.py

@@ -0,0 +1,41 @@
+"""empty message
+
+Revision ID: 0048_job_scheduled_time
+Revises: 0047_ukvi_spelling
+Create Date: 2016-08-24 13:21:51.744526
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '0048_job_scheduled_time'
+down_revision = '0047_ukvi_spelling'
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade():
+    op.create_table('job_status',
+    sa.Column('name', sa.String(length=255), nullable=False),
+    sa.PrimaryKeyConstraint('name')
+    )
+    op.add_column('jobs', sa.Column('job_status', sa.String(length=255), nullable=True))
+    op.add_column('jobs', sa.Column('scheduled_for', sa.DateTime(), nullable=True))
+    op.create_index(op.f('ix_jobs_job_status'), 'jobs', ['job_status'], unique=False)
+    op.create_index(op.f('ix_jobs_scheduled_for'), 'jobs', ['scheduled_for'], unique=False)
+    op.create_foreign_key(None, 'jobs', 'job_status', ['job_status'], ['name'])
+
+    op.execute("insert into job_status values ('pending')")
+    op.execute("insert into job_status values ('in progress')")
+    op.execute("insert into job_status values ('finished')")
+    op.execute("insert into job_status values ('sending limits exceeded')")
+    op.execute("insert into job_status values ('scheduled')")
+
+
+def downgrade():
+    op.drop_constraint('jobs_job_status_fkey', 'jobs', type_='foreignkey')
+    op.drop_index(op.f('ix_jobs_scheduled_for'), table_name='jobs')
+    op.drop_index(op.f('ix_jobs_job_status'), table_name='jobs')
+    op.drop_column('jobs', 'scheduled_for')
+    op.drop_column('jobs', 'job_status')
+    op.drop_table('job_status')