Complete DDS training workflow and delivery package

backend/app/db/migrations/versions/b5e0f2a3c4d5_active_session_checkpoint.py

@@ -0,0 +1,37 @@
+"""снимки активных занятий для восстановления
+
+Revision ID: b5e0f2a3c4d5
+Revises: a4c9d1e2f3b4
+Create Date: 2026-09-23
+"""
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+
+revision = "b5e0f2a3c4d5"
+down_revision = "a4c9d1e2f3b4"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.add_column("sessions", sa.Column("live_state", postgresql.JSONB(), nullable=True))
+    op.add_column(
+        "sessions",
+        sa.Column("checkpoint_at", sa.DateTime(timezone=True), nullable=True),
+    )
+    op.create_index(
+        "ix_sessions_active_checkpoint",
+        "sessions",
+        ["checkpoint_at"],
+        unique=False,
+        postgresql_where=sa.text("ended_at IS NULL AND live_state IS NOT NULL"),
+    )
+
+
+def downgrade() -> None:
+    op.drop_index("ix_sessions_active_checkpoint", table_name="sessions")
+    op.drop_column("sessions", "checkpoint_at")
+    op.drop_column("sessions", "live_state")