feat(chat): invalidate saved chats on sources sync — versioned stamps, stale marker, Regenerate against the new index

2026-08-30 23:39:15 -04:00
parent ea8e041189
commit 32b7bfd4b3
26 changed files with 2145 additions and 63 deletions
@@ -0,0 +1,66 @@
+"""sources_meta + saved_chats.sources_version: the KB-generation stamp (phase 53)
+
+Revision ID: 0010
+Revises: 0009
+Create Date: 2026-08-30
+
+Phase 53 (invalidate saved chats on sources sync, TODO-derived
+2026-08-30): a saved answer can silently predate the current index,
+because neither sync path (the admin Sync button,
+``scripts/import_docs.py``) records *when the KB last changed*. ONE
+migration carries the whole feature (A13 — one feature, one atomic,
+reversible schema change):
+
+* ``sources_meta`` — a **single-row** counter (``id INTEGER PK
+  DEFAULT 1``, the ``kb_overview`` phase-31 precedent) holding the
+  current **generation** of the knowledge base. The seed row
+  (id 1, version 0) is inserted here — not lazily on first bump — so
+  ``app.rag.sources_meta.current_sources_version`` is a plain PK read.
+  ``version`` is bumped exactly once per KB-changing sync (task 02,
+  change-gated on ``added + updated + pruned > 0``); a failed sync
+  never bumps.
+* ``saved_chats.sources_version`` — ``INTEGER NOT NULL DEFAULT 0``:
+  the generation the conversation was saved against, stamped by the
+  chats API at save time (task 03). Pre-0010 rows come back stamped 0
+  (the pre-counter KB) and go stale on the first bump.
+"""
+from __future__ import annotations
+
+import sqlalchemy as sa
+
+from alembic import op
+
+revision = "0010"
+down_revision = "0009"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "sources_meta",
+        sa.Column("id", sa.Integer(), primary_key=True, server_default=sa.text("1")),
+        sa.Column("version", sa.Integer(), nullable=False, server_default=sa.text("0")),
+        sa.Column(
+            "updated_at",
+            sa.DateTime(timezone=True),
+            nullable=False,
+            server_default=sa.func.now(),
+        ),
+    )
+    # Seed the single row (id 1, version 0): "the pre-counter KB".
+    op.execute(
+        "INSERT INTO sources_meta (id, version, updated_at) VALUES (1, 0, now())"
+    )
+    op.add_column(
+        "saved_chats",
+        sa.Column(
+            "sources_version", sa.Integer(), nullable=False, server_default=sa.text("0")
+        ),
+    )
+
+
+def downgrade() -> None:
+    # Safe order: drop the stamp column first, then the counter table.
+    op.drop_column("saved_chats", "sources_version")
+    op.drop_table("sources_meta")