feat: make chat model routing configurable

ai_knowledge_base_v2/apps/backend/alembic/versions/0019_periodic_reports.py

@@ -25,7 +25,9 @@ def upgrade() -> None:
         sa.Column("period_start", sa.DateTime(), nullable=False),
         sa.Column("period_end", sa.DateTime(), nullable=False),
         sa.Column("title", sa.String(length=160), nullable=False),
-        sa.Column("content", sa.Text(), nullable=False, server_default=""),
+        # MySQL 8.4 rejects literal defaults on TEXT columns. The ORM already
+        # supplies an empty string while a report job is pending.
+        sa.Column("content", sa.Text(), nullable=False),
         sa.Column("source_summary_ids", sa.Text(), nullable=True),
         sa.Column("source_topic_ids", sa.Text(), nullable=True),
         sa.Column("model_name", sa.String(length=100), nullable=True),

ai_knowledge_base_v2/apps/backend/alembic/versions/0020_question_insight_persistence.py

@@ -1,83 +1,79 @@
 """persist cleaned question insights
 
-Revision ID: 0020_question_insight_persistence
+Revision ID: 0020_question_insight_store
 Revises: 0019_periodic_reports
 Create Date: 2026-07-31 00:00:00.000000
 """
 
 from __future__ import annotations
 
-from alembic import op
+from alembic import context, op
 import sqlalchemy as sa
 
 
-revision = "0020_question_insight_persistence"
+revision = "0020_question_insight_store"
 down_revision = "0019_periodic_reports"
 branch_labels = None
 depends_on = None
 
 
 def upgrade() -> None:
-    op.create_table(
-        "sys_question_insight_cleaned_question",
-        sa.Column(
-            "id",
-            sa.BigInteger().with_variant(sa.Integer(), "sqlite"),
-            primary_key=True,
-            autoincrement=True,
-        ),
-        sa.Column("message_id", sa.BigInteger(), nullable=False),
-        sa.Column("session_id", sa.BigInteger(), nullable=False),
-        sa.Column("user_id", sa.BigInteger(), nullable=False),
-        sa.Column("part_index", sa.Integer(), nullable=False),
-        sa.Column("cleaner_version", sa.String(length=20), nullable=False),
-        sa.Column("source_hash", sa.String(length=64), nullable=False),
-        sa.Column("cleaned_text", sa.Text(), nullable=False),
-        sa.Column("normalized_text", sa.Text(), nullable=False),
-        sa.Column("category", sa.String(length=50), nullable=False, server_default="other"),
-        sa.Column("tokens_json", sa.Text(), nullable=False),
-        sa.Column("accepted", sa.Integer(), nullable=False, server_default="1"),
-        sa.Column("filtered_reason", sa.String(length=100), nullable=True),
-        sa.Column("source_created_at", sa.DateTime(), nullable=False),
-        sa.Column("created_at", sa.DateTime(), nullable=False, server_default=sa.func.now()),
-        sa.Column("updated_at", sa.DateTime(), nullable=False, server_default=sa.func.now()),
-        sa.ForeignKeyConstraint(
-            ["message_id"],
-            ["sys_chat_message.id"],
-            ondelete="CASCADE",
-        ),
-        sa.UniqueConstraint(
-            "message_id",
-            "cleaner_version",
-            "part_index",
-            name="uq_question_insight_message_version_part",
-        ),
-    )
-    op.create_index(
-        "ix_sys_question_insight_cleaned_question_session_id",
-        "sys_question_insight_cleaned_question",
-        ["session_id"],
-    )
-    op.create_index(
-        "ix_sys_question_insight_cleaned_question_user_id",
-        "sys_question_insight_cleaned_question",
-        ["user_id"],
-    )
-    op.create_index(
-        "ix_question_insight_version_accepted_created",
-        "sys_question_insight_cleaned_question",
-        ["cleaner_version", "accepted", "source_created_at"],
-    )
-    op.create_index(
-        "ix_question_insight_category_created",
-        "sys_question_insight_cleaned_question",
-        ["category", "source_created_at"],
-    )
-    op.create_index(
-        "ix_question_insight_session_created",
-        "sys_question_insight_cleaned_question",
-        ["session_id", "source_created_at"],
-    )
+    table_name = "sys_question_insight_cleaned_question"
+    table_exists = False
+    existing_indexes: set[str] = set()
+    if not context.is_offline_mode():
+        inspector = sa.inspect(op.get_bind())
+        table_exists = inspector.has_table(table_name)
+        if table_exists:
+            existing_indexes = {item["name"] for item in inspector.get_indexes(table_name)}
+
+    if not table_exists:
+        op.create_table(
+            table_name,
+            sa.Column(
+                "id",
+                sa.BigInteger().with_variant(sa.Integer(), "sqlite"),
+                primary_key=True,
+                autoincrement=True,
+            ),
+            sa.Column("message_id", sa.BigInteger(), nullable=False),
+            sa.Column("session_id", sa.BigInteger(), nullable=False),
+            sa.Column("user_id", sa.BigInteger(), nullable=False),
+            sa.Column("part_index", sa.Integer(), nullable=False),
+            sa.Column("cleaner_version", sa.String(length=20), nullable=False),
+            sa.Column("source_hash", sa.String(length=64), nullable=False),
+            sa.Column("cleaned_text", sa.Text(), nullable=False),
+            sa.Column("normalized_text", sa.Text(), nullable=False),
+            sa.Column("category", sa.String(length=50), nullable=False, server_default="other"),
+            sa.Column("tokens_json", sa.Text(), nullable=False),
+            sa.Column("accepted", sa.Integer(), nullable=False, server_default="1"),
+            sa.Column("filtered_reason", sa.String(length=100), nullable=True),
+            sa.Column("source_created_at", sa.DateTime(), nullable=False),
+            sa.Column("created_at", sa.DateTime(), nullable=False, server_default=sa.func.now()),
+            sa.Column("updated_at", sa.DateTime(), nullable=False, server_default=sa.func.now()),
+            sa.ForeignKeyConstraint(
+                ["message_id"],
+                ["sys_chat_message.id"],
+                ondelete="CASCADE",
+            ),
+            sa.UniqueConstraint(
+                "message_id",
+                "cleaner_version",
+                "part_index",
+                name="uq_question_insight_message_version_part",
+            ),
+        )
+
+    indexes = {
+        "ix_sys_question_insight_cleaned_question_session_id": ["session_id"],
+        "ix_sys_question_insight_cleaned_question_user_id": ["user_id"],
+        "ix_question_insight_version_accepted_created": ["cleaner_version", "accepted", "source_created_at"],
+        "ix_question_insight_category_created": ["category", "source_created_at"],
+        "ix_question_insight_session_created": ["session_id", "source_created_at"],
+    }
+    for index_name, columns in indexes.items():
+        if index_name not in existing_indexes:
+            op.create_index(index_name, table_name, columns)
 
 
 def downgrade() -> None:

ai_knowledge_base_v2/apps/backend/alembic/versions/0021_periodic_report_async_jobs.py

@@ -1,7 +1,7 @@
 """add durable periodic report job fields
 
 Revision ID: 0021_periodic_report_async_jobs
-Revises: 0020_question_insight_persistence
+Revises: 0020_question_insight_store
 Create Date: 2026-07-31 00:00:00.000000
 """
 
@@ -12,7 +12,7 @@ import sqlalchemy as sa
 
 
 revision = "0021_periodic_report_async_jobs"
-down_revision = "0020_question_insight_persistence"
+down_revision = "0020_question_insight_store"
 branch_labels = None
 depends_on = None
 

ai_knowledge_base_v2/apps/backend/alembic/versions/0023_simple_knowledge_model_routing.py

@@ -0,0 +1,71 @@
+"""add simple knowledge model capability
+
+Revision ID: 0023_simple_knowledge_route
+Revises: 0022_model_routing
+"""
+
+from alembic import op
+import sqlalchemy as sa
+
+
+revision = "0023_simple_knowledge_route"
+down_revision = "0022_model_routing"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    # Existing models retain the capability so deployment behavior stays on the
+    # current default model until an administrator explicitly reassigns it.
+    op.add_column(
+        "sys_model",
+        sa.Column("allow_simple_knowledge", sa.Integer(), nullable=False, server_default="1"),
+    )
+    # Materialize the new three-state setting so the admin UI and runtime show
+    # the same value even when the legacy emergency switch had been disabled.
+    op.execute(
+        """
+        INSERT IGNORE INTO sys_system_config (config_key, config_value, description)
+        SELECT
+            'chat_model_routing_mode',
+            CASE
+                WHEN EXISTS (
+                    SELECT 1
+                    FROM sys_system_config
+                    WHERE config_key = 'fixed_info_model_routing_enabled'
+                      AND LOWER(TRIM(config_value)) NOT IN ('1', 'true', 'yes', 'on', '启用')
+                ) THEN 'off'
+                ELSE 'fixed_only'
+            END,
+            '正式问答模型分流规则：off / fixed_only / conservative'
+        """
+    )
+
+
+def downgrade() -> None:
+    # Preserve the closest legacy behavior before removing the new setting.
+    op.execute(
+        """
+        UPDATE sys_system_config AS legacy
+        JOIN sys_system_config AS current_mode
+          ON current_mode.config_key = 'chat_model_routing_mode'
+        SET legacy.config_value = CASE
+            WHEN current_mode.config_value = 'off' THEN 'false'
+            ELSE 'true'
+        END
+        WHERE legacy.config_key = 'fixed_info_model_routing_enabled'
+        """
+    )
+    op.execute(
+        """
+        INSERT IGNORE INTO sys_system_config (config_key, config_value, description)
+        SELECT
+            'fixed_info_model_routing_enabled',
+            CASE WHEN config_value = 'off' THEN 'false' ELSE 'true' END,
+            '固定信息模型分流'
+        FROM sys_system_config
+        WHERE config_key = 'chat_model_routing_mode'
+        """
+    )
+    op.execute("DELETE FROM sys_system_config WHERE config_key = 'chat_model_routing_mode'")
+    op.drop_column("sys_model", "allow_simple_knowledge")