From 2a04148ea1c00d92385c5f48370efd0125748203 Mon Sep 17 00:00:00 2001
From: Pea Tyczynska <pea.tyczynska@digital.cabinet-office.gov.uk>
Date: Wed, 2 Dec 2020 15:59:41 +0000
Subject: [PATCH] Add sequential numbering for broadcast messages

We need that to send broadcast messages using proprietary IBAG
format that Vodafone currently uses.
---
 app/models.py                                 | 19 ++++++++
 .../versions/0334_broadcast_message_number.py | 48 +++++++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 migrations/versions/0334_broadcast_message_number.py

diff --git a/app/models.py b/app/models.py
index 4edf8fac5..494842b6b 100644
--- a/app/models.py
+++ b/app/models.py
@@ -6,6 +6,7 @@ from flask import url_for, current_app
 from sqlalchemy.ext.declarative import declared_attr
 from sqlalchemy.ext.associationproxy import association_proxy
 from sqlalchemy.ext.hybrid import hybrid_property
+from sqlalchemy.schema import Sequence
 from sqlalchemy.dialects.postgresql import (
     UUID,
     JSON,
@@ -2483,6 +2484,24 @@ class BroadcastProviderMessage(db.Model):
     UniqueConstraint(broadcast_event_id, provider)
 
 
+class BroadcastProviderMessageNumber(db.Model):
+    """
+    To send IBAG messages via the CBC proxy to Nokia CBC appliances, Notify must generate and store a numeric
+    message_number alongside the message ID (GUID).
+    Subsequent messages (Update, Cancel) in IBAG format must reference the original message_number & message_id.
+    This model relates broadcast_provider_message_id to that numeric message_number.
+    """
+    __tablename__ = 'broadcast_provider_message_number'
+
+    sequence = Sequence('broadcast_provider_message_number_seq')
+    broadcast_provider_message_number = db.Column(
+        db.Integer, sequence, server_default=sequence.next_value(), primary_key=True
+    )
+    broadcast_provider_message_id = db.Column(
+        UUID(as_uuid=True), db.ForeignKey('broadcast_provider_message.id'), nullable=False
+    )
+
+
 class ServiceBroadcastProviderRestriction(db.Model):
     """
     Most services don't send broadcasts. Of those that do, most send to all broadcast providers.
diff --git a/migrations/versions/0334_broadcast_message_number.py b/migrations/versions/0334_broadcast_message_number.py
new file mode 100644
index 000000000..0e1fd04fb
--- /dev/null
+++ b/migrations/versions/0334_broadcast_message_number.py
@@ -0,0 +1,48 @@
+"""
+
+Revision ID: 0334_broadcast_message_number
+Revises: 0333_service_broadcast_provider
+Create Date: 2020-12-04 15:06:22.544803
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+revision = '0334_broadcast_message_number'
+down_revision = '0333_service_broadcast_provider'
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.execute("create sequence broadcast_provider_message_number_seq")
+    op.create_table(
+        'broadcast_provider_message_number',
+        sa.Column(
+            'broadcast_provider_message_number',
+            sa.Integer(),
+            server_default=sa.text("nextval('broadcast_provider_message_number_seq')"),
+            nullable=False
+        ),
+        sa.Column('broadcast_provider_message_id', postgresql.UUID(as_uuid=True), nullable=False),
+        sa.ForeignKeyConstraint(['broadcast_provider_message_id'], ['broadcast_provider_message.id'], ),
+        sa.PrimaryKeyConstraint('broadcast_provider_message_number')
+    )
+    op.execute(
+        """
+            INSERT INTO
+                broadcast_provider_message_number (broadcast_provider_message_id)
+            SELECT
+                id
+            FROM
+                broadcast_provider_message
+        """
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_table('broadcast_provider_message_number')
+    op.execute("drop sequence broadcast_provider_message_number_seq")
+    # ### end Alembic commands ###