Jun 26 update to the latest codes

migrations/versions/phase31_device_registry.py

@@ -0,0 +1,42 @@
+"""phase31 — add ios_version and last_seen_at to api_device_tokens
+
+Extends the existing api_device_tokens table (phase7) so the admin
+Devices page can show iOS version and time of last app launch.
+Drops the unused device_registrations table created by phase30 if it exists.
+"""
+
+from alembic import op
+
+revision      = 'phase31_device_registry'
+down_revision = 'phase30_device_registry'
+branch_labels = None
+depends_on    = None
+
+
+def upgrade():
+    # Add ios_version column if it doesn't exist
+    op.execute("""
+        ALTER TABLE api_device_tokens
+        ADD COLUMN IF NOT EXISTS ios_version VARCHAR(20) NULL
+    """)
+
+    # Add last_seen_at column if it doesn't exist
+    op.execute("""
+        ALTER TABLE api_device_tokens
+        ADD COLUMN IF NOT EXISTS last_seen_at DATETIME NULL
+    """)
+
+    # Backfill last_seen_at from registered_at for existing rows
+    op.execute("""
+        UPDATE api_device_tokens
+        SET last_seen_at = registered_at
+        WHERE last_seen_at IS NULL
+    """)
+
+    # Drop the incorrectly created device_registrations table from phase30 if present
+    op.execute("DROP TABLE IF EXISTS device_registrations")
+
+
+def downgrade():
+    op.execute("ALTER TABLE api_device_tokens DROP COLUMN IF EXISTS ios_version")
+    op.execute("ALTER TABLE api_device_tokens DROP COLUMN IF EXISTS last_seen_at")