add broadcast_message to database

new broadcast_message table. contains a whole bunch of timestamps, a
couple of user ids for who created and who approved, some
personalisation and a template id/version. areas is a jsonb field - it
is expected that this will be an array, for example `["england",
"wales"]`

intended valid state transitions are as follows, from an initial status
of draft

* draft -> pending-approval, rejected
* pending-approval -> broadcasting, rejected, (draft maybe)
* broadcasting -> completed, cancelled

rejected, completed, cancelled and technical-failure are terminating
states.

also copy across the enum switching code from migration 0060 (adding
letter type).

app/models.py

@@ -2148,3 +2148,65 @@ class ServiceContactList(db.Model):
             "created_at": created_at_in_bst.strftime("%Y-%m-%d %H:%M:%S"),
         }
         return contact_list
+
+
+class BroadcastStatusType(db.Model):
+    __tablename__ = 'broadcast_status_type'
+    DRAFT = 'draft'
+    PENDING_APPROVAL = 'pending-approval'
+    REJECTED = 'rejected'
+    BROADCASTING = 'broadcasting'
+    COMPLETED = 'completed'
+    CANCELLED = 'cancelled'
+    TECHNICAL_FAILURE = 'technical-failure'
+
+    STATUSES = [DRAFT, PENDING_APPROVAL, REJECTED, BROADCASTING, COMPLETED, CANCELLED, TECHNICAL_FAILURE]
+
+    name = db.Column(db.String, primary_key=True)
+
+
+class BroadcastMessage(db.Model):
+    __tablename__ = 'broadcast_message'
+    __table_args__ = (
+        db.ForeignKeyConstraint(
+            ['template_id', 'template_version'],
+            ['templates_history.id', 'templates_history.version'],
+        ),
+        {}
+    )
+
+    id = db.Column(UUID(as_uuid=True), primary_key=True)
+
+    service_id = db.Column(UUID(as_uuid=True), db.ForeignKey('services.id'))
+    service = db.relationship('Service', backref='broadcast_messages')
+
+    template_id = db.Column(UUID(as_uuid=True), nullable=False)
+    template_version = db.Column(db.Integer, nullable=False)
+    template = db.relationship('TemplateHistory', backref='broadcast_messages')
+
+    _personalisation = db.Column(db.String, nullable=True)
+
+    status = db.Column(
+        db.String,
+        db.ForeignKey('broadcast_status_type.name'),
+        nullable=False,
+        default=BroadcastStatusType.DRAFT
+    )
+
+    # these times are related to the actual broadcast, rather than auditing purposes
+    starts_at = db.Column(db.DateTime, nullable=True)
+    finishes_at = db.Column(db.DateTime, nullable=True)  # isn't updated if user cancels
+
+    # these times correspond to when
+    created_at = db.Column(db.DateTime, nullable=False)
+    approved_at = db.Column(db.DateTime, nullable=True)
+    cancelled_at = db.Column(db.DateTime, nullable=True)
+    updated_at = db.Column(db.DateTime, nullable=True, onupdate=datetime.datetime.utcnow)
+
+    created_by_id = db.Column(UUID(as_uuid=True), db.ForeignKey('users.id'), nullable=False)
+    approved_by_id = db.Column(UUID(as_uuid=True), db.ForeignKey('users.id'), nullable=True)
+    cancelled_by_id = db.Column(UUID(as_uuid=True), db.ForeignKey('users.id'), nullable=True)
+
+    created_by = db.relationship('User', foreign_keys=[created_by_id])
+    approved_by = db.relationship('User', foreign_keys=[approved_by_id])
+    cancelled_by = db.relationship('User', foreign_keys=[cancelled_by_id])

migrations/versions/0323_broadcast_message.py

@@ -0,0 +1,98 @@
+"""
+
+Revision ID: 0323_broadcast_message
+Revises: 0322_broadcast_service_perm
+Create Date: 2020-07-02 11:59:38.734650
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.sql import column, func
+from sqlalchemy.dialects import postgresql
+
+from app.models import BroadcastMessage
+
+revision = '0323_broadcast_message'
+down_revision = '0322_broadcast_service_perm'
+
+
+name = 'template_type'
+tmp_name = 'tmp_' + name
+
+old_options = ('sms', 'email', 'letter')
+new_options = old_options + ('broadcast',)
+
+new_type = sa.Enum(*new_options, name=name)
+old_type = sa.Enum(*old_options, name=name)
+
+
+STATUSES = [
+    'draft',
+    'pending-approval',
+    'rejected',
+    'broadcasting',
+    'completed',
+    'cancelled',
+    'technical-failure',
+]
+
+
+def upgrade():
+    op.execute(f'ALTER TYPE {name} RENAME TO {tmp_name}')
+    new_type.create(op.get_bind())
+
+    for table in ['templates', 'templates_history', 'service_contact_list']:
+        op.execute(f'ALTER TABLE {table} ALTER COLUMN template_type TYPE {name} USING template_type::text::{name}')
+
+    op.execute(f'DROP TYPE {tmp_name}')
+
+    broadcast_status_type = op.create_table(
+        'broadcast_status_type',
+        sa.Column('name', sa.String(), nullable=False),
+        sa.PrimaryKeyConstraint('name')
+    )
+    op.bulk_insert(broadcast_status_type, [{'name': state} for state in STATUSES])
+
+    op.create_table(
+        'broadcast_message',
+        sa.Column('id', postgresql.UUID(as_uuid=True), nullable=False),
+        sa.Column('service_id', postgresql.UUID(as_uuid=True)),
+        sa.Column('template_id', postgresql.UUID(as_uuid=True), nullable=False),
+        sa.Column('template_version', sa.Integer(), nullable=False),
+        sa.Column('_personalisation', sa.String()),
+        sa.Column('areas', postgresql.JSONB(none_as_null=True, astext_type=sa.Text())),
+        sa.Column('status', sa.String()),
+        sa.Column('starts_at', sa.DateTime()),
+        sa.Column('finishes_at', sa.DateTime()),
+        sa.Column('created_at', sa.DateTime(), nullable=False),
+        sa.Column('approved_at', sa.DateTime()),
+        sa.Column('cancelled_at', sa.DateTime()),
+        sa.Column('updated_at', sa.DateTime()),
+        sa.Column('created_by_id', postgresql.UUID(as_uuid=True), nullable=False),
+        sa.Column('approved_by_id', postgresql.UUID(as_uuid=True)),
+        sa.Column('cancelled_by_id', postgresql.UUID(as_uuid=True)),
+
+        sa.ForeignKeyConstraint(['approved_by_id'], ['users.id'], ),
+        sa.ForeignKeyConstraint(['cancelled_by_id'], ['users.id'], ),
+        sa.ForeignKeyConstraint(['created_by_id'], ['users.id'], ),
+        sa.ForeignKeyConstraint(['service_id'], ['services.id'], ),
+        sa.ForeignKeyConstraint(['template_id', 'template_version'], ['templates_history.id', 'templates_history.version'], ),
+        sa.PrimaryKeyConstraint('id')
+    )
+
+    op.add_column('templates', sa.Column('broadcast_data', postgresql.JSONB(none_as_null=True, astext_type=sa.Text())))
+    op.add_column('templates_history', sa.Column('broadcast_data', postgresql.JSONB(none_as_null=True, astext_type=sa.Text())))
+
+
+def downgrade():
+    op.execute(f'ALTER TYPE {name} RENAME TO {tmp_name}')
+    old_type.create(op.get_bind())
+
+    for table in ['templates', 'templates_history', 'service_contact_list']:
+        op.execute(f'ALTER TABLE {table} ALTER COLUMN template_type TYPE {name} USING template_type::text::{name}')
+    op.execute(f'DROP TYPE {tmp_name}')
+
+    op.drop_column('templates_history', 'broadcast_data')
+    op.drop_column('templates', 'broadcast_data')
+    op.drop_table('broadcast_message')
+    op.drop_table('broadcast_status_type')

tests/app/template/test_rest.py

@@ -212,6 +212,7 @@ def test_should_raise_error_if_service_does_not_exist_on_create(client, sample_u
 
 
 @pytest.mark.parametrize('permissions, template_type, subject, expected_error', [
+    ([EMAIL_TYPE, SMS_TYPE, LETTER_TYPE], BROADCAST_TYPE, None, {'template_type': ['Creating broadcast message templates is not allowed']}),  # noqa
     ([EMAIL_TYPE], SMS_TYPE, None, {'template_type': ['Creating text message templates is not allowed']}),
     ([SMS_TYPE], EMAIL_TYPE, 'subject', {'template_type': ['Creating email templates is not allowed']}),
     ([SMS_TYPE], LETTER_TYPE, 'subject', {'template_type': ['Creating letter templates is not allowed']}),